GOST R ISO 11439-2010
GOST R ISO 11439−2010 Gas cylinders. High pressure cylinders for storage in the vehicle natural gas as fuel. Specifications
GOST R ISO 11439−2010
Group В66; Д24
NATIONAL STANDARD OF THE RUSSIAN FEDERATION
THE GAS CYLINDERS. HIGH PRESSURE CYLINDERS FOR STORAGE IN THE VEHICLE NATURAL GAS AS FUEL
Specifications
Gas cylinders. High pressure cylinders for the on-board storage of natural gas as a fuel. Specifications
OKS 43.020*
GST 14 1200; 1300 14
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* According to the official website of Rosstandart OKS 43.060.40,
here and further. — Note the manufacturer’s database.
Date of introduction 2012−03−01
Preface
The objectives and principles of standardization in the Russian Federation established by the Federal law of 27 December 2002 N 184-FZ «On technical regulation», and rules for the application of national standards of the Russian Federation — GOST R 1.0−2004 «Standardization in the Russian Federation. The main provisions"
Data on standard
1 PREPARED by the Technical Committee for standardization TC 357 «Steel and cast iron pipes and cylinders» and Open joint stock company «Russian scientific research Institute of pipe industry» (JSC «RosNITI») based on authentic translation into the Russian language of the international standard indicated in paragraph 4, which is FSUE «STANDARTINFORM"
2 SUBMITTED by the Technical Committee for standardization TC 357 «Steel and cast iron pipes and cylinders"
3 APPROVED AND put INTO EFFECT by the Federal Agency for technical regulation and Metrology of December 21, 2010 N 911-St
4 this standard is identical to international standard ISO 11439:2000* «Gas cylinders. High pressure cylinders for storage in the vehicle natural gas used as fuel for vehicles» (ISO 11439:2000 «Gas cylinders — High pressure cylinders for the on-board storage of natural gas as a fuel for automotive vehicles»).
The name of this standard changed with respect to names specified international standard for compliance with GOST R 1.5−2004 (subsection 3.5).
In applying this standard it is recommended to use instead of the referenced international standards corresponding national standards of the Russian Federation, details of which are given in Appendix DB
5 INTRODUCED FOR THE FIRST TIME
Information about the changes to this standard is published in the annually issued reference index «National standards», and the text changes and amendments — in monthly indexes published information «National standards». In case of revision (replacement) or cancellation of this standard a notification will be published in a monthly information index «National standards». Relevant information, notification and lyrics are also posted in the information system of General use — on the official website of the Federal Agency for technical regulation and Metrology on the Internet
Introduction
Cylinders for compressed natural gas used as fuel for vehicles should be as light and at the same time must meet the requirements of safe operation of vessels working under pressure.
This is achieve by:
a) accurate and comprehensive definition of operation conditions as a basis for the design and operation of cylinders;
b) use an appropriate method to evaluate fatigue life under cyclic loading pressure and for the determination of allowable defects in a metal cylinder or lanero;
c) inspection and test design;
d) performing non-destructive testing for testing of all manufactured cylinders;
e) carrying out destructive testing of cylinders and cylinder material taken from each batch of cylinders produced;
f) implementation of the manufacturer’s certified quality management system;
g) periodic technical inspection of cylinders in accordance with the manufacturer’s instructions and the requirements of the inspection authority;
h) establishing by the manufacturer term of safe service of gas cylinders.
Cylinders manufactured in accordance with the requirements of this standard:
a) have a resource fatigue life which exceeds the service life;
b) leak but not rupture under cyclic pressure tests to destruction;
c) have when testing hydraulic pressure to the destruction of the indicators of relationship «voltage at the destructive pressure» to «voltage at the working pressure», which exceeds the values established for the particular design and materials used, and have shatter-proof nature of the destruction.
Consumers cylinders manufactured under this standard must remember that the cylinders are designed for safe operation in accordance with the specified conditions for a specified period of time. Date of expiry of the service life and periodic inspection and indicate on each container, and consumers are responsible for examinations of cylinders in accordance with the manufacturer’s instructions, and for stopping operation of cylinders after the elapsed service time.
In this standard relative to the international standard ISO 11439:2000 includes notes, in which, in accordance with the requirements of «Rules of arrangement and safe operation vessels working under pressure» PB 03−576−03 specified values of the safety factor of not less than 2.4; destructive pressure and number of cycles in the test cylinders for use in the Russian Federation. In addition, in section 10 included the note that completes the marking of a container in accordance with the needs of the national economy of the Russian Federation.
In this standard relative to the international standard ISO 11439:2000 changed some phrases are replaced by some terms and their synonyms conform with the norms of the Russian language and in accordance with the national terminology, the notation of the cylinder in Russian — CNG.
The standards included in Appendix DA, which takes into account the needs of the national economy of the Russian Federation in the production and certification of the cylinders.
In applying this standard it is recommended to use instead of the referenced international standards corresponding national standards of the Russian Federation, details of which are given in Appendix SB.
This standard corresponds to GOST R 51753−2001 «high pressure Cylinders for compressed natural gas used as motor fuel for automotive vehicles», but it has significant differences, which are mainly the following:
— introduced type designation of the cylinders — CNG-1 (CNG-1), CNG-2 (CNG-2), CNG-3 (CNG-3), KPG-4 (CNG-4);
— the requirements of this standard applies to cylinders of any design and capacity, in addition to welded cylinders and cylinders made of corrosion-resistant steels;
the factor of safety of cylinders in the Russian Federation must be not less than 2.4, which meets the requirements of PB 03−576−03;
— design of cylinders shall ensure a «leakage before fracture» in case of loss of cylinder integrity under pressure during operation or testing.
1 Scope
This standard specifies minimum requirements for light weight gas cylinders mass production, intended for storage and use of compressed natural gas under high pressure as a fuel for vehicles in which cylinders are installed. Operating conditions do not include external loads that may arise at collision of vehicles, etc.
This standard applies to cylinders manufactured from steel, aluminium or non-metallic material, any design and manufacturing techniques that match the specified conditions. The standard does not apply to welded cylinders and cylinders made from corrosion-resistant steel.
Cylinders covered by this standard, refer to the following:
— CNG-1 (CNG-1) metal;
— KPG-2 (CNG-2) metal liner reinforced with continuous fibres impregnated with resin (ring winding);
— CNG-3 (CNG-3) metal liner reinforced with continuous fibres impregnated with resin (full winding);
— KPG-4 (CNG-4) is a non-metallic liner, reinforced with continuous fibres impregnated with resin (fully compositional).
Note — Cylinders are manufactured in accordance with ISO 9809−1, ISO 9809−2, ISO 9809−3 and ISO 7866 may be used, provided that their design meets the additional requirements specified in this standard.
2 Normative references
The present standard features references to the following standards*:
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* The table of conformity of national standards international see the link. — Note the manufacturer’s database.
ISO 148:1983* Steel. Impact test Charpy (V-shaped incision)
ISO 148:1983, Steel — Charpy impact test (V-notch)
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* Valid ISO 148−1:2006.
ISO 306:1994* Plastics. The thermoplastic materials. Determination of the softening temperature by Vika (VST)
ISO 306:1994, Plastics — Thermoplastic materials — Determination of Vicat softening temperature (VST)
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* Valid ISO 306:2004.
ISO 527−2:1993 Plastics. Determination of mechanical properties under tension. Part 2. Test conditions for moulding and extrusion plastics (including Technical Corrigendum 1:1994)
ISO 527−2:1993, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and extrusion plastics (incorporating Technical Corrigendum 1:1994)
ISO 2808:1997* Paints and varnishes. Determination of film thickness
ISO 2808:1997, Paints and varnishes — Determination of film thickness
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* Valid ISO 2808:2007.
ISO 4624:2002 Paints and varnishes. Determination of adhesion by the method of separation
ISO 4624:2002, Paints and varnishes — Pull-off test for adhesion.
ISO 6506−1:1999* metal Materials. Definition of hardness Brinell. Part 1. Test method
ISO 6506−1:1999, Metallic materials — Brinell hardness test — Part 1: Test method
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* Valid ISO 6506−1:2005.
ISO 6892:1998* metal Materials. Tensile test at ambient temperature
ISO 6892:1998, Metallic materials — Tensile testing at ambient temperature
_______________
* Valid ISO 6892−1:2009.
ISO 7225:2005 Gas cylinders. Warning labels
ISO 7225, Gas cylinders — Precautionary labels
ISO 7866:1999 gas Cylinders. Gas cylinders made of aluminum alloy seamless reuse. Calculation, design and testing
ISO 7866:1999, Gas cylinders — Refillable seamless aluminium alloy gas cylinders — Design, construction and testing
ISO 9227:1990* Testing of corrosion in artificial atmospheres. Test in salt fog
ISO 9227:1990, Corrosion tests in artificial atmospheres — Salt spray tests
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* Valid ISO 9227:2006.
ISO 9712:1999* non-destructive testing. Qualification and certification of personnel
ISO 9712:1999, Non-destructive testing — Qualification and certification of personnel
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* Valid ISO 9712:2005.
ISO 9809−1:1999 gas Cylinders. Seamless steel gas cylinders-refillable. Design, construction and testing. Part 1. Quenched and tempered steel cylinders with tensile tensile strength less than 1100 MPa
ISO 9809−1:1999, Gas cylinders — Refillable seamless steel gas cylinders — Design, construction and testing — Part 1: Quenched and tempered steel cylinders with tensile strength less than 1100 MPa
ISO 9809−2:2000 gas Cylinders. Seamless steel gas cylinders-refillable. Design, construction and testing. Part 2. Quenched and tempered steel cylinders with tensile strength tensile greater than or equal to 1100 MPa
ISO 9809−2:2000, Gas cylinders — Refillable seamless steel gas cylinders — Design, construction and testing — Part 2: Quenched and tempered steel cylinders with tensile strength greater than or equal to 1100 MPa
ISO 9809−3:2000 gas Cylinders. Seamless steel gas cylinders-refillable. Design, construction and testing. Part 3. The normalized steel cylinders
ISO 9809−3:2000, Gas cylinders — Refillable seamless steel gas cylinders — Design, construction and testing — Part 3: Normalized steel cylinders
ISO 14130:1997 Composite materials reinforced with fibers. Determination of apparent interlaminar shear strength shear method test samples of bars
ISO 14130:1997, Fibre-reinforced plastic composites — Determination of apparent interlaminar shear strength by short-beam method
ASTM D522−93A* Standard method of test of attached organic coatings in bending around the mandrel
ASTM D522−93a, Standard Test Methods for Mandrel Bend Test of Attached Organic Coatings
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* ASTM D522−93A (2007).
ASTM Д1308−87 (1998) Standard test method for effect of household chemicals on clear and pigmented organic coating
ASTM D1308−87 (1998), Standard Test Method for Effect of Household Chemicals on Clear and Pigmented Organic Finishes
_______________
* Acts of ASTM Д1308−02 (2007).
ASTM Д2794−93 (1999)E1 Standard test method for resistance of organic coatings to the effects of rapid deformation (impact)
ASTM D2794−93 (1999)E1 Standard Test Method for Resistance of Organic Coatings to the Effects of Rapid Deformation (Impact)
_______________
* Acts of ASTM Д2794−93 (2004).
ASTM Д3170−87 (1996)e1 Standard test method of coatings on the resistance to chipping
ASTM D3170−87 (1996)e1, Standard Test Method for Chipping Resistance of Coatings
_______________
* Acts of ASTM Д3170−03 (2007).
ASTM Д3418−99 Standard test method for transition temperatures of polymers by differential scanning calorimetry
ASTM D3418−99, Standard Test Method for Transition Temperatures of Polymers by Differential Scanning Calorimetry
_______________
* Acts of ASTM Д3418−08.
ASTM Ж53−93* Standard hardware exposure to light and water (fluorescent UV rays — condensation) for materials with non-metallic properties
ASTM G53−93, Standard Practice for Operating Light and Water-Exposure Apparatus (Fluorescent UV — Condensation Type) for Exposure of Nonmetallic Materials
_______________
* Replaced by ASTM Ж154−06.
NACE TM0177−96 Laboratory testing of metals for resistance to sulfide stress cracking and stress corrosion cracking under tension in the HS-containing environments
NACE TM0177−96, Laboratory Testing of Metals for Resistance to Sulfide Stress Cracking and Stress Corrosion Cracking in HS Environments
_______________
* Acts NASE TM0177−05.
For unequivocal compliance with the requirements of this standard expressed in the dated references, it is recommended to only use this reference standard.
3 Terms and definitions
This standard applies the following terms with respective definitions:
3.1 authorized inspection authority (authorized inspection authority): the Competent inspection authority, approved or recognized by an official body in the country of the consumer to monitor the production and testing of cylinders.
Note — In the Russian Federation it is the Federal service for environmental, technological and nuclear supervision — Rostekhnadzor.
3.2 avtomatizovani (auto-frettage): process step of loading pressure, used in manufacturing composite cylinders with metal liner, which liner extends over the yield strength of the material to permanent plastic deformation.
Note — this results in compressive stresses in the liner and tensile stresses in the fibres at zero internal pressure.
3.3 pressure avtomatizovani (auto-frettage pressure): the pressure inside the cylinder with a shell that is used to establish the required distribution of stresses between the liner and shell.
3.4 batch of composite gas cylinders (composite cylinders batch): a Group of composite cylinders of up to 200 cylinders plus cylinders for destructive testing or, if greater, the cylinders produced sequentially during one shift, from laserow the same size, design, materials and manufacturing technology.
3.5 party metal containers/manerov (batch of metal cylinders/liners): a Group of metal cylinders/manerov of not more than 200 cylinders/lanero plus cylinders/lanery for destructive testing or, if more, the metal cylinders/lanery produced consecutively in one shift and have the same nominal diameter, wall thickness, design, material, fabrication technology, equipment for production and modes of heat treatment.
3.6 party nonmetallic Laneros (batch of non-metallic liners): a Group of non-metallic Laneros of not more than 200 lanero plus lanery for destructive testing or, if greater, non-metallic lanery produced consecutively in one shift and have the same nominal diameter, wall thickness, design, material and fabrication technology.
3.7 failure pressure (burst pressure): the Highest pressure achieved in the container or liner when tested to destruction.
3.8 composite cylinder (composite cylinder): Cylinder made of continuous fibers, impregnated with resin and wound on the surface of metallic or nonmetallic liner.
Note — Composite gas cylinders with non-metallic lanarama referred to as fully composite cylinders with metal lanarama — metallokompleksy.
3.9 winding with controlled-tension (winding tension controlled): process step is used in the manufacture of composite cylinders with a ring winding metal lanero, which resulted in compressive stresses in the liner and tensile stresses in the shell at zero internal pressure are created by winding reinforcing fibers at a high enough tension.
3.10 filling pressure (filling pressure): the Pressure at which the container is filled.
3.11 finished cylinders (cylinders are finished): Completed cylinders that are ready for use, typical of normal production, with identification marks and external coating specified by the manufacturer.
3.12 tank full winding (fully-wrapped cylinder): Cylinder shell, having a reinforcement fiber around the circumference and in the direction of the axis of the cylinder.
3.13 gas temperature (gas temperature): Temperature of gas in the tank.
3.14 a gas cylinder with a ring winding (hoop-wrapped cylinder): Cylinder shell, with the reinforcement fiber is mainly around the circumference on the cylindrical part of the liner so that the fibers do not carry any significant load in the direction of the axis of the cylinder.
3.15 the liner (liner): Inner gas-tight shell of the cylinder, on which is wound reinforcing fibres to achieve the necessary strength.
Note — this standard presents laneri two types: metal laneri that are designed to share the load with the reinforcement fibers, and non-metallic lanery that do not carry load.
3.16 the manufacturer (manufacturer): Person or organization responsible for the design, construction and testing of cylinders.
3.18* shell (over-wrap): the System of reinforcing fibers with the resin applied to the liner.
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* Numbering corresponds to the original. — Note the manufacturer’s database.
3.19 pre-tension (prestress): the Result of applying avtomatizovani or winding with controlled-tension.
3.20 service life (service life): the Period in years during which the cylinders can be used safely in accordance with standard operating conditions.
3.21 steady-state pressure (settled pressure): the pressure of the gas that produces the specified steady-state temperature.
3.22 steady-state temperature (settled temperature): the Uniform gas temperature after the disappearance of any changes in its values caused by filling.
3.23 test pressure (test pressure): the Required pressure applied during the test.
3.24 . working pressure (working pressure): the settled pressure of 20 MPa at a uniform temperature of 15 °C.
4 operating Conditions
4.1 General provisions
4.1.1 Standard operating conditions
Standard operating conditions set forth in this section are the basis for the design, manufacture, inspection, testing and approval of cylinders that must be mounted on the vehicle for storage and use of natural gas as a motor fuel in the ambient temperature.
4.1.2 operation of the cylinders
Installed operating conditions provide information on the safe use of cylinders manufactured in accordance with this standard, designed for:
a) manufacturers of cylinders;
b) consumers of cylinders;
c) designers and installers responsible for the installation of cylinders;
d) designers and owners of equipment used for refueling of cylinders;
e) suppliers of natural gas;
f) inspection bodies that have the authority to control the operation of the cylinders.
4.1.3 service Life
Service life, during which the operation of the cylinders is safe, should be installed by the manufacturer on the basis of the use of cylinders the service conditions defined in this standard. Service life should be no more than 20 years.
For metallic cylinders and cylinders with metal liner, the service life should be determined by the development of fatigue cracks under cyclic testing. Ultrasonic or equivalent non-destructive testing of each container and liner should ensure the absence of defects that exceed the maximum allowable size. This approach allows us to optimize the design and manufacture of light weight cylinders for natural gas use in vehicles.
For a fully composite cylinders with non-metallic lanarama, not bearing load, service life should be supported by appropriate design methods, acceptance tests, design and inspections during manufacture.
4.2 Maximum pressure
This standard is designed for operating pressure of 20 MPa, the steady-state when gas temperature of 15 °C with a maximum filling pressure of 26 MPa. Other working pressures may be applied by adjusting the corresponding coefficient, for example, for a cylinder with a working pressure of 25 MPa will require an increase in the maximum filling pressure of 1.25 times.
Except adjustment pressures in this way, the container shall be designed for safe operation under the following pressures:
a) steady-state pressure of 20 MPa at a settled temperature of 15 °C;
b) maximum pressure of 26 MPa, regardless of filling conditions or temperature.
4.3 Design number of filling cycles
Cylinders must withstand filling at the steady state pressure of 20 MPa and a settled gas temperature of 15 °C is not less than 1000 times during one year of operation.
4.4 temperature Range
4.4.1 the temperature of the gas
Cylinders must withstand:
a) steady-state temperature of gas in cylinders, which may vary from minus 40 °C to + 65 °C;
b) temperature that occur when filling and venting of gas that may change outside the limits specified in 4.4.1 a).
4.4.2 the temperature of the cylinders
Cylinders must withstand:
a) the temperature of the materials of the container from minus 40 °C to + 82 °C;
b) temperatures above 65 °C shall be sufficiently local or of short duration, to the temperature of the gas in the cylinder does not exceed 65 °C, except 4.4.1 b).
4.5 the composition of the gas
4.5.1 General provisions
The design of cylinders shall be suitable for filling with natural gas, the relevant requirements to dry or wet gas as follows. Methanol and/or glycol shall not be intentionally added to natural gas.
4.5.2 Dry gas
The concentration of water vapor in dry gas is less than 32 mg/m(dew point temperature is minus 9 °C at a pressure of 20 MPa).
The composition of dry gas:
hydrogen sulfide and other soluble sulfides — 23 mg/m;
oxygen — 1% (volume fraction);
hydrogen (cylinders of steel with a tensile strength exceeding 950 MPa) — 2% (volume fraction).
4.5.3 Wet gas
The concentration of water vapor in the wet gas is more than 32 mg/m.
The composition of wet gas, not more:
hydrogen sulfide and other soluble sulfides — 23 mg/m;
oxygen — 1% (volume fraction);
carbon dioxide — 4% (volume fraction);
hydrogen is 0.1% (volume fraction).
4.6 the Outer surface of the cylinders
The cylinders are not designed for continuous mechanical or chemical impact, e.g. leakage from cargo that may be transported in vehicles or severe abrasion during bad road conditions.
However, the outer surface of the cylinders, installed in accordance with the attached instructions, must be able to withstand accidental impact of the following factors:
a) water, either by intermittent immersion or spray from the roadway;
b) salt — when operating the vehicle near the ocean or in places where salt is used for melting the ice;
c) ultraviolet radiation from sunlight;
d) impact of gravel;
e) solvents, acids, alkalis, mineral fertilizers;
f) automotive fluids, including gasoline, hydraulic fluids, battery acid, glycol and oils;
g) exhaust gases.
5 production and certification
5.1 Testing and monitoring
Conformity assessment is carried out in accordance with the national rules of the consumer cylinders.
To verify compliance with this standard, the cylinders shall be subjected to acceptance testing in accordance with 5.2, verification and testing in accordance with section 6, 7, 8 or 9.
Test methods are described in detail in appendices A and B. Sample acceptable procedures for the receiving, production and certification of cylinders is given in Appendix C and Appendix DA.
5.2 Acceptance tests
5.2.1 General provisions
Acceptance tests should be performed involving inspection of the authorized body (hereinafter — inspector). The inspector must be competent to perform the verification cylinders.
Acceptance tests consist of two stages:
a) approval of documentation on the cylinders, including the provision of documentation to the inspector, as detailed in 5.2.2;
b) prototype testing under the supervision of the inspector. The material, design, fabrication and testing of a container shall comply with the conditions and requirements to the prototype tests specified in 6.5, 7.5, 8.5 and 9.5 for the particular cylinder design.
5.2.2 Harmonization of documentation
Documentation on the cylinders must be coordinated with the inspector. The manufacturer shall provide the inspector documentation which should contain:
a) information on exploitation in accordance with 5.2.3;
b) design data in accordance with 5.2.4;
c) data in accordance with 5.2.5;
d) quality system in accordance with 5.2.6;
e) characteristics of damage and the size of defects for non-destructive testing in accordance with 5.2.7;
f) a report of the project in accordance with 5.2.8;
g) additional supporting data in accordance with
5.2.3 information about the operation
For information about the operation is designed to provide guidance for individuals and organizations operating and setting cylinders, as well as information for the inspector. Information should include:
a) information about the suitability of the design of the container for operation in the conditions specified in section 4;
b) the lifetime;
c) minimum testing and inspection during exploitation;
d) specifications for safety devices against pressure increase and thermal insulation;
e) specifications for the reference devices, protective coatings and other required, but unrepresented devices;
f) a description of the cylinder design;
g) any other information and instructions necessary to ensure safe operation and inspection of the cylinder.
5.2.4 Design data
5.2.4.1 Drawings
The drawings must contain at least the following:
a) the name and designation, date of approval, number and date of introduction of changes;
b) reference to this standard and the cylinder type;
c) dimensions with tolerances, including details on the forms of bottoms with minimum thicknesses and of openings;
d) the mass of the cylinders, with a tolerance;
e) specifications of materials with minimal mechanical and chemical properties or tolerance; and, for metal cylinders or metal lanero — dened limits of hardness;
f) other data such as pressure range avtomatizovani, minimum test pressure, components of fire protection system, the outer protective coating.
5.2.4.2 report on the stress analysis
Needs to be performed stress analysis by finite element method or other method.
Should be a table with the computed voltage values.
5.2.4.3 the properties of the materials
Should be provided with a detailed description of the materials and tolerances on the properties of materials used in construction. Should also be provided data about the tests, characterizing the mechanical properties and the suitability of materials for use in the conditions described in section 4.
5.2.4.4 Fire protection
Must be submitted to the description of the safety devices against pressure rise and thermal insulation that will protect the cylinder from sudden destruction in the fire conditions specified in A. 15. The study is required to confirm the effectiveness of the installed fire protection system.
5.2.5 manufacturing details
Should be provided with detailed information about all technological manufacturing processes, NDT and production tests of gas cylinders.
Must be set the tolerances for all production processes such as heat treatment, forming bottoms, the proportions of the components of the resin, the tension and the winding speed of the fiber with controlled tension, time and temperature of curing and avtomatizovani.
Must be installed: type of surface treatment, the parameters of the thread, acceptance criteria for ultrasonic testing (or equivalent method), the maximum number of industrial batch.
5.2.6 quality management System
The manufacturer shall define the methods and procedures of quality management in accordance with the quality management system acceptable to the inspector. These methods and procedures must meet the requirements of industrial safety and applicable regulations of the consumer cylinders.
5.2.7 characteristics of the fracture and the defect size for non-destructive testing
The manufacturer shall establish the maximum allowable defect size for non-destructive testing, which will ensure a «leakage before fracture» and will prevent damage to the container during service life due to fatigue.
The maximum allowable defect size shall be established by a method suitable for the liner design. An example of suitable method is given in Appendix D.
5.2.8 Statement of the technical project
The list of documents that provide information as required in 5.2.2 shall be specified in the statement of the technical project for each cylinder design. Must indicate the name, designation, change numbers with dates of introduction for each document. All documents must be signed by the developer.
5.2.9 Additional supporting data
Should be provided with additional data that confirm the possibility of application of the proposed material or a specific cylinder design, if they were used previously in other conditions.
5.3 acceptance tests
If the results of the acceptance tests in accordance with 5.2 (coordination of documentation) and prototype testing in accordance with 6.5, 7.5, 8.5 or 9.5 (for the particular cylinder design) is satisfactory, the manufacturer and the inspector shall be drawn up and signed an act of acceptance tests. An example of such a act is presented in figure E. 2 of Annex E.
6 Requirements for metal cylinders for CNG type-1 (CNG-1)
6.1 General
This standard does not provide design formulas, and specifies the allowable stress or strain, but requires that the conformity of the design was determined by relevant calculations and confirmed by tests. Cylinders must withstand the testing of materials, acceptance testing, qualification and acceptance tests of the party specified in this standard.
The design should provide the kind of damage «leakage before fracture» with the possible destruction of the tank under pressure during normal operation. Leak in a metal container shall only occur with the development of fatigue cracks.
6.2 Materials
6.2.1 General requirements
The materials used must be suitable for the operating conditions specified in section 4. The materials of construction must be compatible.
6.2.2 Control of the chemical composition
6.2.2.1 Steel
Steel should be raskisleniya aluminum and/or silicon and having a structure with a predominance of fine grains.
Chemical composition of all steels shall be declared and defined, at least:
a) carbon, manganese, aluminium and silicon in all cases;
b) chromium, Nickel, molybdenum, boron and vanadium and other specially added alloying elements.
The content of sulfur and phosphorus on the results of the analysis of melting should not exceed the values given in table 1.
Table 1 Maximum sulphur and phosphorus contents
| Tensile strength, MPa |
<950 |
| |
| Content, %, not more |
Sulfur | 0,020 | 0,010 |
| Phosphorus | 0,020 | 0,020 | |
| Sulfur and phosphorus | 0,030 | 0,025 | |
6.2.2.2 Aluminium
Aluminum alloys can be used for the manufacture of cylinders, if they meet all the requirements of this standard and contain lead and bismuth is not more than 0,003%.
Note: the List of registered alloy is Aluminum Association called «Registration data on international designations for alloys and chemical composition limits for wrought aluminum and alloy forging aluminum».
6.3 design Requirements
6.3.1 Test pressure
The test pressure used in manufacture shall be 30 MPa (1.5 times of working pressure).
6.3.2 pressure
Valid pressure should be at least 45 MPa.
Note — For the Russian Federation valid failure pressure — not less than 2.4 48 MPa (where
working pressure, MPa; 2,4 — service factor of the cylinder for the Russian Federation).
6.3.3 stress analysis
The stresses in the cylinder shall be designed for a working pressure of 20 MPa, the test pressure and the calculated failure pressure. The calculations are made to determine the minimum calculated wall thickness.
6.3.4 Maximum defect size
Must be defined the maximum allowable defect size at any location of the metal container so that the container met the requirements of the cyclic pressure test and «leak before fracture».
The allowable defect size for non-destructive testing should be determined by an appropriate method, for example, as indicated in Appendix D.
6.3.5 Neck cylinders
The cylinders may have one or two necks located at the bottoms. The centreline of the holes of openings shall coincide with the longitudinal axis of the cylinder.
6.3.6 Fire protection
The cylinder design shall be protected by safety devices against overpressure. The cylinder, its materials, pressure relief devices and any added insulation or protective material shall be designed in conjunction to provide the necessary safety in case of fire in the conditions described in A. 15. The manufacturer may specify an alternate location of safety devices on the vehicle with the aim of achieving security.
Safety devices against pressure increase must comply with a standard acceptable to the inspector of the consumer cylinders.
6.3.7 Fixtures
If there is a ring cap, Shoe or other device to support it must be made of a material compatible with the material of the container and must be securely attached by any method except welding and soldering soft or hard solder.
6.4 Design and workmanship
6.4.1 Forming the bottoms
Before performing the forming the bottoms of each workpiece of the cylinder must pass the control of wall thickness and surface quality.
Not allowed forming of the deaf bottoms when using billets of aluminum alloys.
Bottoms of steel cylinders after forming should be checked by nondestructive method of control.
In the process of forming the bottoms of the metal to be added should not.
6.4.2 Heat treatment
After forming the heads and necks of the cylinders is subjected to heat treatment to hardness specified for the design. Local heat treatment not allowed.
6.4.3 Thread of the neck
Thread needs to be executed cleanly and smoothly without discontinuity of the surface and shall meet the requirements of the standard.
6.4.4 Protection against environmental influences
The outer surface of the cylinders shall conform to the requirements of the climate test in an acidic medium specified in A. 14. For protecting the outer surface may include one of the following ways:
a) a metallic protective coating (e.g., metal spraying of aluminium, anodizing);
b) an organic protective coating (e.g., ink); if the coating is part of the design, it must meet the requirements specified in A. 9;
c) a protective coating, resistant to chemicals listed in A. 14.
Any coatings applied to cylinders shall be such that their application process did not adversely affect the mechanical properties of the cylinder. The coating should not hinder the subsequent control operation. The manufacturer shall provide instructions on coating treatment during such inspection to preserve the integrity of the cylinder.
The manufacturer recommended test climatic effects of the environment, which evaluates the strength of the coating (see Annex F).
6.5 test Procedure test sample
6.5.1 General requirements
The prototype test should be carried out for each new design, on finished cylinders, which are experienced manufacture and have identification marks. Sample cylinders should be selected and tested as specified in 6.5.2, under the supervision of the inspector. If the test is subjected to more cylinders than required by this standard, all test results should be documented.
6.5.2 Testing of a prototype
6.5.2.1 tests Required
The inspector shall select cylinders for test and be present when the following acceptance tests:
— specified
— specified
— specified
is specified
— specified
— specified
6.5.2.2 material Tests for steel cylinders
Test material for steel cylinders should be carried out as follows:
a) tensile test
Steel properties of the finished cylinder shall be determined by A. 1 and shall be as specified in A. 1 requirements;
b) test the impact strength
Toughness of steel finished cylinder shall be determined in A. 2 and shall be as specified in A. 2 requirements;
c) test for resistance to sulfide stress cracking
If the tensile strength of steel exceeding 950 MPa, the steel finished cylinder shall be tested for resistance to sulphide stress cracking A. 3 and should correspond to those in A. 3 requirements.
6.5.2.3 Test cylinder material aluminum alloy
Test cylinder material aluminum alloy should be carried out as follows:
a) tensile test
The properties of aluminium alloy in the finished cylinder shall be determined by A. 1 and shall be as specified in A. 1 requirements;
b) tests for intergranular corrosion
Aluminum alloys shall conform to the requirements of the tests for intergranular corrosion, made according to A. 4;
c) tests for resistance to cracking under constant load
Aluminum alloys shall conform to the requirements of the tests for resistance to cracking under constant load, performed by A. 5.
6.5.2.4 Test hydraulic pressure to the destruction
Three cylinders shall be subjected to hydraulic pressure until fracture in accordance with A. 12. Failure pressure of the cylinder shall exceed the minimum failure pressure calculated by the stress for a given design, and must be at least 45 MPa.
Note — For the Russian Federation Deplete the cylinder pressure is 48 MPa.
6.5.2.5 Cycling test pressure at ambient temperature
Two cylinders shall be subjected to a cyclic test pressure at ambient temperature in accordance with A. 13 to failure, or at least 45,000 cycles.
Cylinders must withstand without fracture not less than 1000cycles (where the
— specified service life, years). The cylinders, which has withstood more than 1000
cycles should give leak but not rupture. The cylinders which are not destroyed within 45,000 cycles shall be destroyed by continued cyclical pressure test or by increasing the hydraulic pressure. The number of cycles to failure and location of fracture must be documented.
6.5.2.6 Test for «leak prior to fracture"
Test for «leak prior to fracture» should be held at A. 6, and should correspond to those in A. 6 requirements.
6.5.2.7 fire Test
One or two cylinders shall be tested according to A. 15 and shall be as specified in A. 15 requirements.
6.5.2.8 Test cross
One cylinder shall be tested according to A. 16 and shall be as specified in A. 16 requirements.
6.5.3 design Change
A design change is any change in the selection of structural materials or resizing.
Minor design changes are allowed to test on an abbreviated program. Design changes presented in table 2 require only the testing of the prototype, as indicated in the table.
Table 2 — Types of tests when you change the design of CNG cylinders type-1 (CNG-1)
| Design change | Type of test | |||||
| The destruction of hydraulic pressure | Cyclic change of pressure at ambient temperature |
Leakage to failure | Fire | Cross | ||
| Section of this standard | ||||||
| A. 12. | A. 13 | A. 6 | A. 15 | A. 16 | ||
| The material of the metal container |
+ | + | + | + | + | |
The change in diameter |
+ | + | - | - | - | |
| The diameter change >20% |
+ | + | + | + | + | |
The length change of |
+ | - | - | + |
- | |
| The length change >50% |
+ | + | - | + |
- | |
The change in working pressure is <20% |
+ | + | - | - | - | |
| The shape of the bottom |
+ | + | - | - | - | |
| Hole size |
+ | + | - | - | - | |
| The change in technology |
+ | + | - | - | - | |
| Safety device |
- | - | - | + | - | |
| ||||||
6.6 batch Test
6.6.1 General requirements
Batch testing shall be conducted on finished cylinders representing mass production and having identification marks. Cylinders for testing should be selected from each lot at random. If the test is subjected to more cylinders than required by this standard, all test results should be documented. Use the samples subjected to heat treatment, which are finished cylinders.
Batch tests carried out at the production of cylinders for production qualification testing installation (first industrial) party and in the process of production acceptance testing of each manufactured batch.
Cylinders manufactured in accordance with ISO 9809−1, ISO 9809−2, ISO 9809−3 ISO 7866 or not required to be subjected to cyclic pressure tests, provided that in the acceptance test of the prototype cylinders can withstand without fracture not less than 15,000 cycles of pressure change from 2 to 30 MPa (in accordance with the testing method presented in A. 6) or not less than 30000 cycles of pressure change from 2 to 26 MPa (in accordance with the testing method presented in A. 13).
6.6.2 tests Required
6.6.2.1 Each batch of cylinders shall be subjected to the following tests:
a) on one cylinder
1) test the hydraulic pressure for destruction in accordance with A. 12;
b) on one cylinder
1) check the dimensions for compliance to the drawings (see
2) tensile test in accordance with A. 1; the test results shall conform to the requirements of the design documentation (see
3) for steel cylinders, three impact tests in bending A. 2; the test results must meet the requirements specified in A. 2;
4) if a protective coating is a part of the design, the test coverage in the party must be conducted in accordance with A. 24. If the coating does not meet the requirements of A. 24, the batch shall be subjected to 100% control to identify the cylinders with such a defective coating. Defective coating on all the cylinders may be removed and applied again. Then should be carried out repeated tests of the coating in the party.
Allowed to conduct the tensile test and the impact bending on the sample-the witness, subjected to a heat treatment.
All cylinders provided in the test batch do not meet the specified requirements shall be subject to the procedures established in 6.9.
6.6.2.2 Additionally needs to be carried out cyclic pressure test on finished cylinders in accordance with A. 13 at the frequency of the tests:
a) initially, one cylinder from each batch shall be subjected to cyclic pressure testing for 1000cycles, but not less than 15000 cycles;
b) if on 10 sequential batches of containers of the same structural number (i.e., materials and processes the same within minor design changes, see 6.5.3), none of the cylinders subjected to cyclic testing at the cycles (minimum 22,500 cycles) then the cyclic pressure test can be performed on one cylinder from each of the following five parties;
c) if on 10 sequential batches of containers of the same construction row none of the cylinders subjected to cyclic testing at the cycles (not less than 30,000 cycles), the cyclic pressure test can be performed on one cylinder from each of the following 10 parties;
d) if more than three months passed since the last cyclic test pressure, the container of the next batch should be subjected to cyclic pressure testing to keep the testing party with a reduced frequency
e) if the container is subjected to cyclic pressure tests with a reduced frequency
If the container is in the cycles (not less than 15000 cycles), should be determined and rectified the reason for the discrepancy, according to the procedures specified in 6.9. Then you must repeat the cyclic pressure test on the three additional cylinders from this batch. If at least one of the three additional cylinders can not withstand 1000
cycles (not less than 15,000 cycles), then this party must be rejected.
6.7 Control of each cylinder
Control should be applied to all cylinders of the party. Non-destructive testing should be carried out in accordance with a standard acceptable to the inspector.
Each cylinder in the manufacturing process and after manufacture shall be subjected to:
a) control non-destructive method in accordance with the application or other tested equivalent method to confirm that the maximum size of an existing defect does not exceed the size specified for the package design; as specified
b) measuring the control of the main size and weight of the finished cylinders shall be within the tolerances specified for the design;
c) visual inspection of surface quality, especially surface and deep drawing of a neck or shoulder part of the forged or nakatannyh bottoms;
d) verification of markings;
e) control the hardness of the material of the cylinders, heat-treated, in accordance with A. 8. Hardness values shall be within the limits established for the design;
f) a hydraulic pressure test in accordance with A. 11. When choosing option 1 the manufacturer shall define the appropriate limit of the residual volumetric expansion for the test pressure used; this residual extension should be no more than 10% of the total volumetric expansion measured at the test pressure.
6.8 Document the quality of the party
If satisfactory results of the testing party in accordance with 6.6 and 6.7 should be issued document the quality of the party. An example of such a document is presented in figure E. 1 of Annex E.
6.9 non-compliance monitoring and testing
In the case of non-compliance monitoring and testing should be carried out re-inspection and testing or re-heat treatment and retesting:
a) upon receipt of unsatisfactory results of inspection and testing for errors in their conduct or errors in measurement should be repeated inspection and testing. If the results of the repeated inspection and testing is satisfactory, the initial results do not take into account;
b) if there were no errors in the inspection and test, it should be the cause of unsatisfactory results:
1) if the reason for unsatisfactory results is the heat treatment, the manufacturer may subject the cylinders that fail inspection and testing, re-heat treatment, i.e., if the unsatisfactory results obtained in the test representing the prototype or batch cylinders shall be done re-heat treatment of all the represented cylinders prior to re-testing. However, if the unsatisfactory results obtained by chance under the control of each cylinder, but these cylinders must be re-heat treated and re-verification:
— in any re-heat treatment of cylinders shall be stored a minimum guaranteed wall thickness;
only testing of a prototype or party, is required to confirm the suitability of a batch shall be performed again. If one or more indicators of the control and tests prove unsatisfactory, all cylinders of this batch shall be rejected;
2) if the inspection and test defects not due to heat treatment, all defective cylinders shall be rejected or repaired by an appropriate method; if the repaired cylinders were control necessary during the repair, they should be accepted as valid.
7 Requirements for CNG cylinders type-2 (CNG-2) with a ring winding
7.1 General provisions
This standard does not provide design formulas, and specifies the allowable stress or strain, but requires that the conformity of the design was determined by relevant calculations and confirmed by tests. Cylinders must withstand the testing of materials, acceptance testing, qualification and acceptance tests of the party specified in this standard.
When the pressure in the cylinder of this type the displacement of the composite shell and the metal liner occurs together in the longitudinal direction. Due to different manufacturing techniques cylinders this standard does not give a specific method for design.
The design should provide the kind of damage «leakage before fracture» with the possible destruction of the tank under pressure during normal operation. Leak in a metal liner should occur only with the development of fatigue cracks.
7.2 Materials
7.2.1 General requirements
The materials used must be suitable for the operating conditions specified in section 4. The materials of construction must be compatible.
7.2.2 Control of the chemical composition
7.2.2.1 Steel
Steel should be raskisleniya aluminum and/or silicon and having a structure with a predominance of fine grains.
Chemical composition of all steels shall be declared and defined, at least:
a) carbon, manganese, aluminium and silicon in all cases;
b) chromium, Nickel, molybdenum, boron and vanadium and other specially added alloying elements.
The content of sulfur and phosphorus on the results of the analysis of melting should not exceed the values given in table 3.
Table 3 — Maximum content of sulphur and phosphorus
| Tensile strength, MPa |
<950 |
| |
| Content, %, not more |
Sulfur | 0,020 | 0,010 |
| Phosphorus | 0,020 | 0,020 | |
| Sulfur and phosphorus | 0,030 | 0,025 | |
7.2.2.2 Aluminium
Aluminum alloys can be used for the manufacture of cylinders, if they meet all the requirements of this standard and contain lead and bismuth is not more than 0,003%.
Note: the List of registered alloy is Aluminum Association called «Registration data on international designations for alloys and chemical composition limits for wrought aluminum and alloy forging aluminum».
7.2.3 Composite materials
7.2.3.1 Resin
The material for impregnation may be thermosetting or thermoplastic resins. Examples of suitable main matrix materials are epoxy, modified epoxy, thermosetting plastics based on polyesters and vinyl esters, thermoplastic materials based on polyethylene and polyamide.
The glass transition temperature of the material resin should be determined in accordance with ASTM Д3418−99.
7.2.3.2 Fiber
As the reinforcing material should serve as glass, aramid or carbon fibers. If you use carbon fiber design must have means to prevent galvanic corrosion in metal elements of the container.
The manufacturer of the cylinders must have: a technical specifications for composite materials; the recommendations of the manufacturer of materials for storage, conditions and shelf life; manufacturer’s certificate for the material, indicating that each batch meets the specification requirements. Fiber manufacturer must confirm that the properties of the fiber material specifications for the manufacture of these products.
7.3 design Requirements
7.3.1 Test pressure
The test pressure used in manufacture shall be 30 MPa (1.5 times of working pressure).
7.3.2 pressure and factors of safety fiber
For metal liner actual failure pressure shall be not less than 26 MPa.
The estimated failure pressure shall be not less than the values shown in table 4. The composite shell should be designed for strength under constant and cyclic loading. The strength should be achieved by matching or exceeding the values of safety factors in the strength of composite shells listed in table 4. The factor of safety is defined as the fiber stress at calculated minimum breaking pressure divided by the stress in the fibre at working pressure. The factor of safety of the cylinder is determined as a valid failure pressure of the cylinder divided by the working pressure.
Note — For the Russian Federation the factor of safety of the container — not less than 2.4. Deplete the actual cylinder pressure — not less than 48 MPa.
Table 4 — Minimum estimated values of destructive pressure and safety factors for fiber CNG cylinders type-2 (CNG-2)
| Fiber type | The factor of safety |
Pressure, MPa |
| Glass |
2,75 | 50 |
| Aramid |
Of 2.35 (2,40) |
47 (48) |
| Carbon |
2,35 (2,50) |
47 (50) |
| Mixed |
||
| ||
Calculations of factor of safety of fibre should include:
a) the method of analysis of characteristics of non-linear materials (special purpose computer program or a calculation program by finite element method);
b) simulation curve of voltages from elasto-plastic deformations for the material of the liner;
c) modeling mechanical properties of composite materials;
d) the calculations in avtomatizovani pressure, zero pressure after autofrettage, working pressure and the minimum breaking pressure;
e) calculate pre-stresses from winding tension;
f) selecting the minimum calculated Deplete the pressure in such a way that the calculated stress at this pressure divided by the calculated stress at working pressure meets the requirements factor of safety for the used fiber;
g) calculation of load distribution between two or more different fibers based on different moduli of elasticity of these fibers, for cylinders with mixed reinforcement. Requirements for factors of safety for each individual fibre type shall conform to the values specified in table 4.
Check factors of safety fiber can be conducted using strain gauges. Applicable method given in Annex G.
7.3.3 stress analysis
Stresses in composite and in the liner after prestress shall be calculated for the 0 and 20 MPa, test pressure and design pressure Deplete. The calculation is carried out taking into account the nonlinear behavior of the material of the liner is to define the minimum design wall thickness.
For designs that use avtomatizovani to ensure the pre-tension must be calculated in pressure range avtomatizovani. For designs that use wound with controlled tension to ensure the pre-tension must be calculated tension required in each layer of the composite material, and subsequent pre-tension in the liner.
7.3.4 Maximum defect size
The maximum allowable defect size at any location of the metal liner should be such that the container met the requirements of the cyclic pressure test and «leak before fracture». Non-destructive testing method must detect the maximum allowable defect size.
The allowable defect size for non-destructive testing should be determined by an appropriate method, for example, as indicated in Appendix D.
7.3.5 Neck cylinders
The cylinders may have one or two necks located at the bottoms. The centreline of the holes of openings shall coincide with the longitudinal axis of the cylinder.
7.3.6 Fire protection
The cylinder design shall be protected by safety devices against overpressure. The cylinder, its materials, pressure relief devices and any added insulation or protective material shall be designed in conjunction to provide the necessary safety in case of fire in the conditions described in A. 15. The manufacturer may specify an alternate location of safety devices on the vehicle with the aim of achieving security.
Safety devices against pressure increase must comply with a standard acceptable to the inspector of the consumer cylinders.
7.4 Design and workmanship
7.4.1 General provisions
The composite cylinder shall be made of the liner with a sheath of continuous fibers. The operation of winding the fiber should be computer or mechanical control. Fiber must be applied under controlled tension during winding. After winding is complete, thermosetting resins shall be cured by heating in accordance with a previously determined and controlled by the chart «time — temperature».
7.4.2 laner
Metal fabrication of the liner shall conform to the requirements set out in 7.2, 7.3.2 and
7.4.3 Thread of the neck
Thread needs to be executed cleanly and smoothly without discontinuity of the surface and shall meet the requirements of the standard.
7.4.4 Shell
7.4.4.1 fibre Winding
Cylinders must be manufactured by winding fiber. During winding of the important variables must be controlled within specified tolerances, and documented. These variables can include (but are not limited to) the following:
a) the type and parameters of the fiber;
b) manner of impregnation;
c) the tension of the winding;
d) winding speed;
e) number of rovings;
f) the width of the tape;
g) type of resin and composition;
h) the temperature of the resin;
i) the temperature of the liner;
j) the winding angle.
7.4.4.2 Curing thermosetting resins
The thermosetting resin shall be cured after filament winding. The curing cycle (i.e. the graph «time — temperature») should be documented.
The maximum time and the curing temperature for cylinders with manerami of aluminum alloys must be less than time and temperature which adversely affect metal properties.
7.4.4.3 Avtomatizovani
Avtomatizovani must be fulfilled before the test hydraulic pressure. Pressure avtomatizovani must be within the limits laid down in 7.3.3; the manufacturer must install a suitable method of pressure control.
7.4.5 Protection from environmental influences
The outer surface of the cylinders shall conform to the requirements of the climate test in an acidic medium specified in A. 14. For protecting the outer surface may include one of the following ways:
a) a metallic protective coating (e.g., metal spraying of aluminium, anodizing);
b) the application of suitable fibers and a binder material (e.g. carbon fibre in resin);
c) an organic protective coating (e.g., ink); if the coating is part of the design, it must meet the requirements specified in A. 9;
d) protective coating, resistant to chemicals listed in A. 14.
Any coatings applied to cylinders shall be such that their application process did not adversely affect the mechanical properties of the cylinder. The coating should not hinder the subsequent control operation. The manufacturer shall provide instructions on coating treatment during such inspection to preserve the integrity of the cylinder.
The manufacturer recommended test climatic effects of the environment, which evaluates the strength of the coating (see Annex F).
7.5 test Procedure a test sample
7.5.1 General requirements
The prototype test should be carried out for each new design, on finished cylinders, which are experienced manufacture and have identification marks. Sample cylinders or Laneros should choose and experience as specified in 7.5.2, under the supervision of the inspector. If tests expose more of the cylinders or Laneros than required by this standard, all test results should be documented.
7.5.2 Testing of a prototype
7.5.2.1 tests Required
The inspector shall select cylinders and lanery for tests and to be present when the following acceptance tests:
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— listed
7.5.2.2 material Tests for steel Laneros
Test material steel Laneros should be conducted as follows:
a) tensile test
Steel properties of the finished liner shall be determined by A. 1 and shall be as specified in A. 1 requirements;
b) test the impact strength
Toughness of steel finished liner shall be determined in A. 2 and shall be as specified in A. 2 requirements;
c) test for resistance to sulfide stress cracking
If the tensile strength of steel exceeding 950 MPa, the steel of the finished liner shall be tested for resistance to sulphide stress cracking A. 3 and should correspond to those in A. 3 requirements.
7.5.2.3 Test material Laneros of aluminum alloy
Test material Laneros of aluminum alloy should be carried out as follows:
a) tensile test
The properties of aluminium alloy in the finished liner shall be determined by A. 1 and shall be as specified in A. 1 requirements;
b) tests for intergranular corrosion
Aluminum alloys shall conform to the requirements of the tests for intergranular corrosion, made according to A. 4;
c) tests for resistance to cracking under constant load
Aluminum alloys shall conform to the requirements of the tests for resistance to cracking under constant load, performed by A. 5.
7.5.2.4 Testing hydraulic pressure to the destruction
a) One liner shall be subjected to hydraulic pressure until fracture in accordance with A. 12. Pressure shall exceed the minimum pressure specified for the liner design.
b) Three cylinders shall be subjected to a hydraulic test to destruction in accordance with A. 12. The estimated failure pressure for fiber should not be less than the breaking pressure specified in table 4. The container pressure shall not be less than the pressure specified
7.5.2.5 Cycling test pressure at ambient temperature
Two cylinders shall be subjected to a cyclic test pressure at ambient temperature in accordance with A. 13 to failure, or at least 45,000 cycles.
Cylinders must withstand without fracture not less than 1000cycles (where the
— specified service life, years). The cylinders, which has withstood more than 1000
cycles should give leak but not rupture. The cylinders which are not destroyed within 45,000 cycles shall be destroyed by continued cyclical pressure test or by increasing the hydraulic pressure. The number of cycles to failure and location of fracture must be documented.
7.5.2.6 Test for «leak prior to fracture"
Test for «leak prior to fracture» should be held at A. 6, and should correspond to those in A. 6 requirements.
7.5.2.7 the fire Test
One or two cylinders shall be tested according to A. 15 and shall be as specified in A. 15 requirements.
7.5.2.8 Test cross
One cylinder shall be tested according to A. 16 and shall be as specified in A. 16 requirements.
7.5.2.9 climate test in an acidic environment
One cylinder shall be tested according to A. 14 and must conform to the requirements of A. 14.
Additional testing for environmental impact is presented in Appendix F.
7.5.2.10 Test valid defects
One cylinder shall be tested according to A. 17 and shall be as specified in A. 17 requirements.
7.5.2.11 creep Testing at high temperature
In designs where the glass transition temperature of the resin does not exceed 102 °C, one cylinder shall be tested according to A. 18 and shall be as specified in A. 18 requirements.
7.5.2.12 Accelerated testing to destruction under stress
One cylinder shall be tested according to A. 19 and shall be as specified in A. 19 requirements.
7.5.2.13 Cyclic pressure testing under extreme temperatures
One cylinder shall be tested according to A. 7 and shall be as specified in A. 7 requirements.
7.5.2.14 Strength resin shear
Materials based on resin shall be tested according to A. 26 and must conform to the requirements of A. 26.
7.5.3 design Change
A design change is any change in the selection of structural materials or resizing.
Minor design changes are allowed to test on an abbreviated program. Design changes presented in table 5, only require testing of the prototype, as indicated in the table.
Table 5 — Types of tests when you change the design of CNG cylinders type-2 (CNG-2)
| Design change |
Type of test | |||||||
| The development tion hydraulic cal pressure tion |
Cyclical pressure variation in temp- the temperature of the environment |
Fire wait bone |
Pros- fire |
Climate control MATIC |
The admissible substantial defect |
Crawling- honor at high temp- the temperature |
The development the circumstances under voltage statement | |
| Section of this standard | ||||||||
| A. 12. | A. 13 | A. 15 | A. 16 | A. 14 | A. 17 | A. 18 | A. 19 | |
| Manufacturer of fiber |
+ | + | - | - | - | - | + | + |
| The material of the metal liner |
+ | + | + | + | + | + | + | + |
| Fiber |
+ | + | + | + | + | + | + | + |
| Resin |
- | - | - | + | + | + | + | + |
The change in diameter |
+ | + | - | - | - | - | - | - |
| The diameter change >20% |
+ | + | + | + | - | + | - | - |
Change the diameter |
+ | - | + |
- | - | - | - | - |
| Change the diameter > 50% |
+ | + | + |
- | - | - | - | - |
Changing the operating pressure |
+ | + | - | - | - | - | - | - |
| The shape of the bottom |
+ | + | - | - | - | - | - | - |
| Hole size |
+ | + | - | - | - | - | - | - |
| Change cover |
- | - | - | - | + | - | - | - |
| The change in technology |
+ | + | - | - | - | - | - | - |
| Safety device |
- | - | + | - | - | - | - | - |
| ||||||||
7.6 batch Test
7.6.1 General requirements
Batch testing shall be conducted on finished cylinders representing mass production and having identification marks. Cylinders and lanery for testing should be selected from each lot at random. If the test is subjected to more cylinders and lanero than required by this standard, all test results should be documented. Defects in the shell to avtomatizovani or before the hydraulic pressure test shell can be completely removed and replaced.
7.6.2 Required tests
7.6.2.1 Each batch of cylinders shall be subjected to the following tests:
a) on one cylinder
1) test the hydraulic pressure for destruction in accordance with A. 12.
If unsatisfactory test results, you must follow the procedures specified in 7.9;
b) on one container or liner
1) check the dimensions for compliance to the drawings (see
2) tensile test according to A. 1; the test results shall conform to the requirements of the design documentation (see
3) for steel Laneros three testing the impact strength according to A. 2; the test results must meet the requirements specified in A. 2;
4) if a protective coating is a part of the design, the test coverage in the party must be conducted in accordance with A. 24. If the coating does not meet the requirements of A. 24, the batch shall be subjected to 100% control to identify the cylinders with such a defective coating. Defective coating on all the cylinders may be stripped using a technology that does not affect the integrity of the shell, and applied again. Then should be carried out repeated tests of the coating in the party.
Allowed to conduct the tensile test and the impact bending on the sample-the witness, subjected to a heat treatment.
All cylinders or lanery presented in the trials of the party and do not meet these requirements shall be subject to the procedures established in 7.9.
7.6.2.2 Additionally needs to be carried out cyclic pressure test on finished cylinders in accordance with A. 13 at the frequency of the tests:
a) initially, one cylinder from each batch shall be subjected to cyclic pressure testing for 1000cycles, but not less than 15000 cycles;
b) if on 10 sequential batches of containers of the same structural number (i.e., materials and processes the same within minor design changes, see 7.5.3), none of the cylinders subjected to cyclic testing cycles (minimum 22,500 cycles) then the cyclic pressure test can be performed on one cylinder from each of the following five parties;
c) if on 10 sequential batches of containers of the same construction row none of the cylinders subjected to cyclic testing cycles (not less than 30,000 cycles), the cyclic pressure test can be performed on one cylinder from each of the following 10 parties;
d) if more than three months passed since the last cyclic test pressure, the container of the next batch should be subjected to cyclic pressure testing to keep the testing party with a reduced frequency
e) if the container is subjected to cyclic pressure tests with a reduced frequency
If the container according cycles (not less than 15000 cycles), should be determined and rectified the reason for the discrepancy in accordance with the procedures specified in 7.9. Then you must repeat the cyclic pressure test on the three additional cylinders from this batch. If at least one of the three additional cylinders can not withstand 1000
cycles (not less than 15,000 cycles), then this party must be rejected.
7.7 Control of each cylinder
Control should be applied to all cylinders of the party. Non-destructive testing should be carried out in accordance with a standard acceptable to the inspector.
Each cylinder in the manufacturing process and after manufacture shall be subjected to:
a) control of metal Laneros a non-destructive method in accordance with the application or other tested equivalent method to confirm that the maximum size of an existing defect does not exceed the size specified for the package design; as specified
b) measuring the control of the main size and weight of the finished cylinders, lanero and shells, which must be within the tolerances specified for the design;
c) visual inspection of surface quality, especially surface and deep drawing of a neck or shoulder part of the forged or nakatannyh bottoms;
d) verification of markings;
e) control of hardness of metal Laneros in accordance with A. 8 carried out after the final heat treatment. Hardness values shall be within the limits established for the design;
f) a hydraulic pressure test in accordance with A. 11, option 1. The manufacturer shall define the appropriate limit of the residual volumetric expansion for the test pressure used; this residual extension should be no more than 5% of the total volumetric expansion measured at the test pressure.
7.8 Document quality party
If satisfactory results of the testing party in accordance with 7.6 and 7.7 shall be made by a document of quality of the party. An example of such a document is presented in figure E. 1 of Annex E.
7.9 non-compliance monitoring and testing
In the case of non-compliance monitoring and testing should be carried out re-inspection and testing or re-heat treatment and retesting:
a) upon receipt of unsatisfactory results of inspection and testing for errors in their conduct or errors in measurement should be repeated inspection and testing. If the results of the repeated inspection and testing is satisfactory, the initial results do not take into account;
b) if there were no errors in the inspection and test, it should be the cause of unsatisfactory results:
1) if the reason for unsatisfactory results is the heat treatment, the manufacturer may subject the cylinders that fail inspection and testing, re-heat treatment, i.e., if the unsatisfactory results obtained in the test representing the prototype or batch cylinders shall be done re-heat treatment of all the represented cylinders prior to re-testing. However, if the unsatisfactory results obtained by chance under the control of each cylinder, but these cylinders must be re-heat treated and re-verification:
— in any re-heat treatment of cylinders shall be stored a minimum guaranteed wall thickness;
only testing of a prototype or party, is required to confirm the suitability of a batch shall be performed again. If one or more indicators of the control and tests prove unsatisfactory, all cylinders of this batch shall be rejected;
2) if the inspection and test defects not due to heat treatment, all defective cylinders shall be rejected or repaired by an appropriate method; if the repaired cylinders were control necessary during the repair, they should be accepted as valid.
8 Requirements for CNG cylinders of type-3 (CNG-3) with a full winding
8.1 General provisions
This standard does not provide design formulas, and specifies the allowable stress or strain, but requires that the conformity of the design was determined by relevant calculations and confirmed by tests. Cylinders must withstand the testing of materials, acceptance testing, qualification and acceptance tests of the party specified in this standard.
When the pressure in the cylinder of this type the displacement of the composite shell and the metal liner occurs together. Due to different manufacturing techniques cylinders this standard does not give a specific method for design.
The design should provide the kind of damage «leakage before fracture» with the possible destruction of the tank under pressure during normal operation. Leak in a metal liner should occur only with the development of fatigue cracks.
8.2 Materials
8.2.1 General requirements
The materials used must be suitable for the operating conditions specified in section 4. The materials of construction must be compatible.
8.2.2 a chemical composition Control
8.2.2.1 Steel
Steel should be raskisleniya aluminum and/or silicon and having a structure with a predominance of fine grains.
Chemical composition of all steels shall be declared and defined, at least:
a) carbon, manganese, aluminium and silicon in all cases;
b) chromium, Nickel, molybdenum, boron and vanadium and other specially added alloying elements.
The content of sulfur and phosphorus on the results of the analysis of melting should not exceed the values given in table 6.
Table 6 — Maximum sulfur and phosphorus
| Tensile strength, MPa |
<950 |
| |
| Content, %, not more | Sulfur |
0,020 | 0,010 |
| Phosphorus | 0,020 | 0,020 | |
| Sulfur and phosphorus | 0,030 | 0,025 | |
8.2.2.2 Aluminium
Aluminum alloys can be used for the manufacture of cylinders, if they meet all the requirements of this standard and contain lead and bismuth is not more than 0,003%.
Note: the List of registered alloy is Aluminum Association called «Registration data on international designations for alloys and chemical composition limits for wrought aluminum and alloy forging aluminum».
8.2.3 Composite materials
8.2.3.1 Resin
The material for impregnation may be thermosetting or thermoplastic resins. Examples of suitable main matrix materials are epoxy, modified epoxy, thermosetting plastics based on polyesters and vinyl esters, thermoplastic materials based on polyethylene and polyamide.
The glass transition temperature of the material resin should be determined in accordance with ASTM Д3418−99.
8.2.3.2 Fiber
As the reinforcing material should serve as glass, aramid or carbon fibers. If you use carbon fiber design must have means to prevent galvanic corrosion in metal elements of the container.
The manufacturer of the cylinders must have: a technical specifications for composite materials; the recommendations of the manufacturer of materials for storage, conditions and shelf life; manufacturer’s certificate for the material, indicating that each batch meets the specification requirements. Fiber manufacturer must confirm that the properties of the fiber material specifications for the manufacture of these products.
8.3 design Requirements
8.3.1 Test pressure
The test pressure used in manufacture shall be 30 MPa (1.5 times of working pressure).
8.3.2 pressure and factors of safety fiber
The estimated failure pressure shall be not less than the values shown in table 7. The composite shell should be designed for strength under constant and cyclic loading. The strength should be achieved by matching or exceeding the values of safety factors in the strength of composite shells listed in table 7. The factor of safety is defined as the fiber stress at calculated minimum breaking pressure divided by the stress in the fibre at working pressure. The factor of safety of the cylinder is determined as a valid failure pressure of the cylinder divided by the working pressure.
Note — For the Russian Federation the factor of safety of the container — not less than 2.4. Deplete the actual cylinder pressure — not less than 48 MPa.
Table 7 — Minimum design values Deplete the pressure and safety factor fiber for the cylinder type CNG-3 (CNG-3)
| Fiber type | The factor of safety |
Pressure, MPa |
| Glass |
3,65 | 70 |
| Aramid |
3,10 | 60 (62) |
| Carbon |
Of 2.35 (2,40) | 47 (48) |
| Mixed |
||
| ||
Calculations of factor of safety of fibre should include:
a) the method of analysis of characteristics of non-linear materials (special purpose computer program or program of finite elements);
b) simulation curve of voltages from elasto-plastic deformations for the material of the liner;
c) modeling mechanical properties of composite materials;
d) the calculations in avtomatizovani pressure, zero pressure after autofrettage, working pressure and the minimum breaking pressure;
e) calculate pre-stresses from winding tension;
f) selecting the minimum calculated Deplete the pressure in such a way that the calculated stress at this pressure divided by the calculated stress at working pressure meets the requirements factor of safety for the used fiber;
g) calculation of load distribution between two or more different fibers based on different moduli of elasticity of these fibers, for cylinders with mixed reinforcement. Requirements for factors of safety for each individual fibre type shall conform to the values specified in table 7.
Check factors of safety fiber can be conducted using strain gauges. Applicable method given in Annex G.
8.3.3 Calculation of stresses
After the pre-tension must be calculated circumferential and axial stresses in the composite shell and in the liner for 0 and 20 MPa, test pressure and design pressure Deplete. The calculation is carried out taking into account the nonlinear behavior of the material of the liner is to define the minimum design wall thickness.
Must be rated pressure range avtomatizovani.
8.3.4 the Maximum size of the defect
The maximum allowable defect size at any location of the metal liner should be such that the container met the requirements of the cyclic pressure test and «leak before fracture». Non-destructive testing method must detect the maximum allowable defect size.
The allowable defect size for non-destructive testing should be determined by an appropriate method, for example, as indicated in Appendix D.
8.3.5 Neck cylinders
The cylinders may have one or two necks located at the bottoms. The centreline of the holes of openings shall coincide with the longitudinal axis of the cylinder.
8.3.6 Fire protection
The cylinder design shall be protected by safety devices against overpressure. The cylinder, its materials, pressure relief devices and any added insulation or protective material shall be designed in conjunction to provide the necessary safety in case of fire in the conditions described in A. 15. The manufacturer may specify an alternate location of safety devices on the vehicle with the aim of achieving security.
Safety devices against pressure increase must comply with a standard acceptable to the inspector of the consumer cylinders.
8.4 Design and workmanship
8.4.1 General provisions
The composite cylinder shall be made of the liner with a sheath of continuous fibers. The operation of winding the fiber should be computer or mechanical control. Fiber must be applied under controlled tension during winding. After winding is complete, thermosetting resins shall be cured by heating in accordance with a previously determined and controlled by the chart «time — temperature».
8.4.2 laner
Metal fabrication of the liner shall conform to the requirements set out in 8.2, 8.3.2 and
The compressive stress in the liner at zero pressure and 15 °C should not cause warping or appearance of folds in the liner.
8.4.3 the Carving of a mouth
Thread needs to be executed cleanly and smoothly without discontinuity of the surface and shall meet the requirements of the standard.
8.4.4 Shell
8.4.4.1 the winding of the fibers
Cylinders must be manufactured by winding fiber. During winding of the important variables must be controlled within specified tolerances, and documented. These variables can include (but are not limited to) the following:
a) the type and parameters of the fiber;
b) manner of impregnation;
c) the tension of the winding;
d) winding speed;
e) number of rovings;
f) the width of the tape;
g) type of resin and composition;
h) the temperature of the resin;
i) the temperature of the liner;
j) the winding angle.
8.4.4.2 Curing thermosetting resins
The thermosetting resin shall be cured after filament winding. The curing cycle (i.e. the graph «time — temperature») should be documented.
The maximum time and the curing temperature for cylinders with manerami of aluminum alloys must be less than time and temperature which adversely affect metal properties.
8.4.4.3 Avtomatizovani
Avtomatizovani must be fulfilled before the test hydraulic pressure. Pressure avtomatizovani must be within the limits prescribed in 8.3.3; the manufacturer must install a suitable method of pressure control.
8.4.5 Protection against environmental influences
The outer surface of the cylinders shall conform to the requirements of the climate test in an acidic medium specified in A. 14. For protecting the outer surface may include one of the following ways:
a) a metallic protective coating (e.g., metal spraying of aluminium, anodizing);
b) the application of suitable fibers and a binder material (e.g. carbon fibre in resin);
c) an organic protective coating (e.g., paint); if exterior coating is part of the design, it must meet the requirements specified in A. 9;
d) protective coating, resistant to chemicals listed in A. 14.
Any coatings applied to cylinders shall be such that their application process did not adversely affect the mechanical properties of the cylinder. The coating should not hinder the subsequent control operation. The manufacturer shall provide instructions on coating treatment during such inspection to preserve the integrity of the cylinder.
The manufacturer recommended test climatic effects of the environment, which evaluates the strength of the coating (see Annex F).
8.5 test Procedure test sample
8.5.1 General requirements
The prototype test should be carried out for each new design, on finished cylinders, which are experienced manufacture and have identification marks. Sample cylinders or Laneros should choose and experience as specified in 8.5.2, under the supervision of the inspector. If tests expose more of the cylinders or Laneros than required by this standard, all test results should be documented.
8.5.2 testing of the prototype
8.5.2.1 tests Required
The inspector shall select cylinders and lanery for tests and to be present when the following acceptance tests:
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— specified
— listed
— listed
— listed
— listed
— listed
8.5.2.2 Test material steel Laneros
Test material steel Laneros should be conducted as follows:
a) tensile test
Steel properties of the finished liner shall be determined by A. 1 and shall be as specified in A. 1 requirements;
b) test the impact strength
Toughness of steel finished liner shall be determined in A. 2 and shall be as specified in A. 2 requirements;
c) test for resistance to sulfide stress cracking
If the tensile strength of steel exceeding 950 MPa, the steel finished cylinder shall be tested according to A. 3 and should correspond to those in A. 3 requirements.
8.5.2.3 Test material Laneros of aluminum alloy
Test material Laneros of aluminum alloy should be carried out as follows:
a) tensile test
The properties of aluminium alloy in the finished liner shall be determined by A. 1 and shall be as specified in A. 1 requirements;
b) tests for intergranular corrosion
Aluminum alloys shall conform to the requirements of the tests for intergranular corrosion, made according to A. 4;
c) tests for resistance to cracking under constant load
Aluminum alloys shall conform to the requirements of the tests for resistance to cracking under constant load, performed by A. 5.
8.5.2.4 the Test of hydraulic pressure to the destruction
Three cylinders shall be subjected to hydraulic pressure until fracture in accordance with A. 12. The estimated failure pressure for fiber should not be less than the breaking pressure specified in table 7. The container pressure shall not be less than the pressure specified
8.5.2.5 Cycling test pressure at ambient temperature
Two cylinders shall be subjected to a cyclic test pressure at ambient temperature in accordance with A. 13 to failure, or at least 45,000 cycles.
Cylinders must withstand without fracture not less than 1000cycles (where the
— specified service life, years). The cylinders, which has withstood more than 1000
cycles should give leak but not rupture. The cylinders which are not destroyed within 45,000 cycles shall be destroyed by continued cyclical pressure test or by increasing the hydraulic pressure. The number of cycles to failure and location of fracture must be documented.
8.5.2.6 Test for «leak prior to fracture"
Test for «leak prior to fracture» should be held at A. 6, and should correspond to those in A. 6 requirements.
8.5.2.7 fire Test
One or two cylinders shall be tested according to A. 15 and shall be as specified in A. 15 requirements.
8.5.2.8 Test cross
One cylinder shall be tested according to A. 16 and shall be as specified in A. 16 requirements.
8.5.2.9 climate test in an acidic environment
One cylinder shall be tested according to A. 14 and must conform to the requirements of A. 14.
Additional testing for environmental impact is presented in Appendix F.
8.5.2.10 Test valid defects
One cylinder shall be tested according to A. 17 and shall be as specified in A. 17 requirements.
8.5.2.11 creep Testing at high temperature
In designs where the glass transition temperature of the resin does not exceed 102 °C, one cylinder shall be tested according to A. 18 and shall be as specified in A. 18 requirements.
8.5.2.12 Accelerated testing to destruction under stress
One cylinder shall be tested according to A. 19 and shall be as specified in A. 19 requirements.
8.5.2.13 Cyclic pressure testing under extreme temperatures
One cylinder shall be tested according to A. 7 and shall be as specified in A. 7 requirements.
8.5.2.14 Strength resin shear
Materials based on resin shall be tested according to A. 26 and must conform to the requirements of A. 26.
8.5.2.15 impact Test in the fall
One or more finished cylinders shall be tested for the blow to A. 20 and shall be as specified in A. 20 requirements.
8.5.3 design Change
A design change is any change in the selection of structural materials or resizing.
Minor design changes are allowed to test on an abbreviated program. Design changes presented in table 8, only require testing of the prototype, as indicated in the table.
Table 8 — Types of tests when you change the cylinder design type CNG-3 (CNG-3)
| Design change |
Type of test | ||||||||
| The development solution of the hydraulic likes- Kim pressure tion |
Scrappers- as the pressure changes with the temp- the temperature environ- guide environment |
Fire wait bone |
Pro- arrows |
Climate control tices- some |
The admissible substantial defect |
Crawling- honor at high temp- the temperature |
The development the circumstances under voltage statement |
Hit when Pade- research Institute | |
| Section of this standard | |||||||||
| A. 12. |
A. 13 | A. 15 | A. 16 | A. 14 | A. 17 | A. 18 | A. 19 | A. 20 | |
| Manufacturer of fiber |
+ | + | - | - | - | - | + | + | + |
| The material of the metal liner |
+ | + | + | + | + | + | + | + | + |
| Fiber |
+ | + | + | + | + | + | + | + | + |
| Resin |
- | - | - | + | + | + | + | + | + |
The change in diameter |
+ | + | - | - | - | - | - | - | - |
| The diameter change >20% |
+ | + | + | + | - | + | - | - | + |
Change the diameter |
+ | - | + |
- | - | - | - | - | - |
| Change the diameter >50% |
+ | + | + |
- | - | - | - | - | + |
Changing the operating pressure |
+ | + | - | - | - | - | - | - | - |
| The shape of the bottom |
+ | + | - | - | - | - | - | - | - |
| Hole size |
+ | + | - | - | - | - | - | - | - |
| Change cover |
- | - | - | - | + | - | - | - | - |
| The change in production technology |
+ | + | - | - | - | - | - | - | - |
| Safety device |
- | - | + | - | - | - | - | - | - |
| |||||||||
8.6 batch Test
8.6.1 General requirements
Batch testing shall be conducted on finished cylinders representing mass production and having identification marks. Cylinders and lanery for testing should be selected from each lot at random. If the test is subjected to more cylinders and lanero than required by this standard, all test results should be documented. Defects in the shell to avtomatizovani or before the hydraulic pressure test shell can be completely removed and replaced.
8.6.2 tests Required
8.6.2.1 Each batch of cylinders shall be subjected to the following tests:
a) on one cylinder
1) test the hydraulic pressure for destruction in accordance with A. 12.
If unsatisfactory test results, you must follow the procedures specified in 8.9;
b) on one container or liner
1) check the dimensions for compliance to the drawings (see
2) tensile test according to A. 1; the test results shall conform to the requirements of the design documentation (see
3) for steel Laneros three testing the impact strength according to A. 2; the test results must meet the requirements specified in A. 2;
4) if a protective coating is a part of the design, the test coverage in the party must be conducted in accordance with A. 24. If the coating does not meet the requirements of A. 24, the batch shall be subjected to 100% control to identify the cylinders with such a defective coating. Defective coating on all the cylinders may be stripped using a technology that does not affect the integrity of the shell, and applied again. Then should be carried out repeated tests of the coating in the party.
Allowed to conduct the tensile test and the impact bending on the sample-the witness, subjected to a heat treatment.
All cylinders or lanery presented in the trials of the party and do not meet these requirements shall be subject to the procedures established in 8.9.
8.6.2.2 should be carried out cyclic pressure test on finished cylinders in accordance with A. 13 at the frequency of the tests:
a) initially, one cylinder from each batch shall be subjected to cyclic pressure testing for 1000cycles, but not less than 15000 cycles;
b) if on 10 sequential batches of containers of the same structural number (i.e., materials and processes the same within minor design changes, see 8.5.3), none of the cylinders subjected to cyclic test cycles (minimum 22,500 cycles) then the cyclic pressure test can be performed on one cylinder from each of the following five parties;
c) if on 10 sequential batches of containers of the same construction row none of the cylinders subjected to cyclic test cycles (not less than 30,000 cycles), the cyclic pressure test can be performed on one cylinder from each of the following 10 parties;
d) if more than three months passed since the last cyclic test pressure, the container of the next batch should be subjected to cyclic pressure testing to keep the testing party with a reduced frequency
e) if the container is subjected to cyclic pressure tests with a reduced frequency
If the container for cycles (not less than 15000 cycles), should be determined and rectified the reason for the discrepancy in accordance with the procedures specified in 8.9. Then you must repeat the cyclic pressure test on the three additional cylinders from this batch. If at least one of the three additional cylinders can not withstand 1000
cycles (not less than 15,000 cycles), then this party must be rejected.
8.7 Control of each cylinder
Control should be applied to all cylinders of the party. Non-destructive testing should be carried out in accordance with a standard acceptable to the inspector.
Each cylinder in the manufacturing process and after manufacture shall be subjected to:
a) control of metal Laneros a non-destructive method in accordance with the application or other tested equivalent method to confirm that the maximum size of an existing defect does not exceed the size specified for the package design; as specified
b) measuring the control of the main size and weight of the finished cylinders, lanero and shells, which must be within the tolerances specified for the design;
c) visual inspection of surface quality, especially surface and deep drawing of a neck or shoulder part of the forged or nakatannyh bottoms;
d) verification of markings;
e) control of hardness of metal Laneros in accordance with A. 8 carried out after the final heat treatment. Hardness values shall be within the limits established for the design;
f) a hydraulic pressure test in accordance with A. 11, option 1. The manufacturer shall define the appropriate limit of the residual volumetric expansion for the test pressure used; this residual extension should be no more than 5% of the total volumetric expansion measured at the test pressure.
8.8 Document quality party
If satisfactory results of the testing party in accordance with 8.6 and 8.7 shall be made by a document of quality of the party. An example of such a document is presented in figure E. 1 of Annex E.
8.9 non-compliance monitoring and testing
In the case of non-compliance monitoring and testing should be carried out re-inspection and testing or re-heat treatment and retesting:
a) upon receipt of unsatisfactory results of inspection and testing for errors in their conduct or errors in measurement should be repeated inspection and testing. If the results of the repeated inspection and testing is satisfactory, the initial results do not take into account;
b) if there were no errors in the inspection and test, it should be the cause of unsatisfactory results:
1) if the reason for unsatisfactory results is the heat treatment, the manufacturer may subject the cylinders that fail inspection and testing, re-heat treatment, i.e., if the unsatisfactory results obtained in the test representing the prototype or batch cylinders shall be done re-heat treatment of all the represented cylinders prior to re-testing. However, if the unsatisfactory results obtained by chance under the control of each cylinder, but these cylinders must be re-heat treated and re-verification:
— in any re-heat treatment of cylinders shall be stored a minimum guaranteed wall thickness;
only testing of a prototype or party, is required to confirm the suitability of a batch shall be performed again. If one or more indicators of the control and tests prove unsatisfactory, all cylinders of this batch shall be rejected;
2) if the inspection and test defects not due to heat treatment, all defective cylinders shall be rejected or repaired by an appropriate method; if the repaired cylinders were control necessary during the repair, they should be accepted as valid.
9 Requirements for composite cylinders for CNG type-4 (CNG-4)
9.1 General provisions
This standard does not provide design formulas, and specifies the allowable stress or strain, but requires that the conformity of the design was determined by relevant calculations and confirmed by tests. Cylinders must withstand the testing of materials, acceptance testing, qualification and acceptance tests of the party specified in this standard.
The design should provide the kind of damage «leakage before fracture» with the possible destruction of the tank under pressure during normal operation.
9.2 Materials
9.2.1 General requirements
The materials used must be suitable for the operating conditions specified in section 4. The materials of construction must be compatible.
9.2.2 Resin
The material for impregnation may be thermosetting or thermoplastic resins. Examples of suitable main matrix materials are epoxy, modified epoxy, thermosetting plastics based on polyesters and vinyl esters, thermoplastic materials based on polyethylene and polyamide.
The glass transition temperature of the material resin should be determined in accordance with ASTM Д3418−99.
9.2.3 Fiber
As the reinforcing material should serve as glass, aramid or carbon fibers. If you use carbon fiber design must have means to prevent galvanic corrosion in metal elements of the container.
The manufacturer of the cylinders must have: a technical specifications for composite materials; the recommendations of the manufacturer of materials for storage, conditions and shelf life; manufacturer’s certificate for the material, indicating that each batch meets the specification requirements. Fiber manufacturer must confirm that the properties of the fiber material specifications for the manufacture of these products.
9.2.4 Plastic lanery
The polymeric material should be applied in the conditions specified in section 4.
9.2.5 Metal items
Metal items attached to the nonmetallic liner must be made of a material applicable to the condition specified in section 4.
