GOST 801-78

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  ГОСТ 801-78

GOST 801−78 Steel bearing. Technical specifications (with Changes N 1, 2, 3, 4, 5, 6)

GOST 801−78

Group В32

INTERSTATE STANDARD

STEEL BEARING

Specifications

Bearing steel. Specifications

ISS 77.080.20
OKP 09 5600

Date of introduction 1980−01−01

The decision of the State Committee USSR on standards on August 17, 1978 N 2236 date of introduction is established 01.01.80

Limitation of actions taken by Protocol No. 3−93 Interstate Council for standardization, Metrology and certification (ICS 5−6-93)

REPLACE GOST 801−60

EDITION (September 2004), with Changes N 1, 2, 3, 4, 5, 6, approved in June 1987, December 1988, October 1989, July 1990, April 1999, June 2001 (IUS 10−87, 3−89, 1−90, 11−90, 7−99, 9−2001), Amendment (ICS 12−2002).

Change No. 5 adopted by the Interstate Council for standardization, Metrology and certification (Protocol No. 7 of April 26, 1995)

The name of the state	The name of the national authority for standardization
The Republic Of Belarus	Gosstandart Of Belarus
The Republic Of Kazakhstan	Gosstandart Of The Republic Of Kazakhstan
Russian Federation	Gosstandart Of Russia
Ukraine	Gosstandart Of Ukraine

Change No. 6 adopted by the Interstate Council for standardization, Metrology and certification (Protocol No. 21 dated may 30, 2002)

The name of the state	The name of the national authority for standardization
The Republic Of Azerbaijan	Azgosstandart
The Republic Of Armenia	Armastajad
The Republic Of Belarus	Gosstandart Of The Republic Of Belarus
The Republic Of Kazakhstan	Gosstandart Of The Republic Of Kazakhstan
The Kyrgyz Republic	Kyrgyzstandard
The Republic Of Moldova	Moldovastandart
Russian Federation	Gosstandart Of Russia
The Republic Of Tajikistan	Tajikstandart
Turkmenistan	The MDCSU «Turkmenstandartlary"
The Republic Of Uzbekistan	Standards

This standard applies to hot rolled diameter or thickness up to 250 mm inclusive, calibrated steel and steel with special surface (with or without drawing drawing), intended for the manufacture of rings, balls and rollers of bearings.

Steel shall be manufactured in electric arc furnaces with pumping without vacuum (as agreed with the customer), acid open-hearth furnaces or by electroslag remelting.

As part of the rules of the chemical composition of this standard also applies to ingots, slabs, pipes, sheets, forgings, rolled and wire.

The standard fully complies ST SEV 6436−88.

(Changed edition, Rev. N 3, 5, 6).

1. BRAND

1.1. Bearing steel SHKH15 produce brands, SHKH4, SHKH15SG and SHKH20SG.

Note. In the designation of steel grades the letters and numbers mean:

Ø at the beginning of the brand bearing;

X — chromium alloy;

4, 15, 20 — mass fraction of chromium (0,4%; 1,5%; 2,0%);

SG — alloyed silicon and manganese;

Ø at the end of the marks obtained by electroslag remelting;

At the end of the brand — manufactured vacuum.

(Changed edition, Rev. N 1).

2. ASSORTMENT

2.1. Steel manufactures round, square and rectangular section bars, strips and coils.

2.1. Hot rolled and calibrated steel according to the requirements of surface quality depending on the further processing is divided into groups:

OH — for cold mechanical processing (turning, milling, recess, etc.);

OG for hot forming;

XB — for cold upsetting;

XIII — for cold forming;

By state of material:

without heat treatment;

thermally processed (annealed) — Oh.

(Added, Rev. N 1).

2.2. In shape, dimensions, limit deviations, the steel shall conform to the requirements:

hot — rolled round GOST 2590−88*;
______________
* On the territory of the Russian Federation GOST 2590−2006, here and hereafter. — Note the manufacturer’s database.

— hot rolled square GOST 2591−88*;
______________
* On the territory of the Russian Federation GOST 2591−2006, here and hereafter. — Note the manufacturer’s database.

— processing the square — the existing normative documents;

— hot-rolled strip, GOST 103−76*;
______________
* On the territory of the Russian Federation GOST 103−2006, here and hereafter. — Note the manufacturer’s database.

— calibrated round kvalitet h11 with extra dimensions (Annex 1) — GOST 7417−75;

— round with special surface finish tolerance h11 groups and G — GOST 14955−77.

(Changed edition, Rev. N 5).

2.3. Steel shall be manufactured in length:

2,8−4,0 m — hot-rolled round with a diameter of 65 mm;

2.0−4.0 m — hot-rolled round with a diameter of 65 mm;

2.0−4.0 m — hot-rolled square;

3,0−4,5 m and calibrated with special surface finish.

Allowed bars and rods of diameter or thickness up to 65 mm is not shorter than 2 m not more than 10% of the batch weight.

By agreement with consumer it is allowed manufacture of steel in length up to 6 m.

2.4. Calibrated steel with special surface finish diameter up to 25 mm can be produced in bars or rolls, more than 25 mm — in bars.

2.5. The mass of the roll must be:

50−300 kg — steel diameter to 12 mm inclusive;

200−500 kg for steel with a diameter of over 12 mm.

Hanks allowed smaller mass in the amount not exceeding 10% of the batch weight.

2.6. The inner diameter of the coils should be:

hot rolled steel

	diameter	6	to 12 mm 550−850 mm;
	«	St. 12	«28 mm — 750−1100 mm;

calibrated steel with special surface finish

	diameter		to 5 mm 200−550 mm;
	«	St. 5	«12 mm 550−850 mm;
	«	«12	«25 mm x 750−1100 mm.

2.7. The curvature of the annealed hot-rolled bars and strips should not exceed 0.4% of length.

At the request of the consumer for the manufacture of bearing rings on the automatic lines the curvature of the annealed hot-rolled bars shall not exceed 0.2% of the length.

The curvature of bars calibrated steel must not exceed:

for bars with diameter up to 25 mm — 0,2% of the length;

for bars with diameter over 25 mm — 0,1% of the length.

The curvature of bars in steel with special surface finish shall not exceed 0.05% of the length.

(Changed edition, Rev. N 3).

2.8. The ends of the rods, coils and strips, hot-rolled, calibrated steel and steel with special surface finishes must be cut or broken without bends and burrs.

Allowed burrs and crushing tips for hot-rolled steel by an amount not outputting the profile limit for positive deviations in diameter or thickness, and calibrated with special surface finish is outside the nominal size.

When the edit bars on kosovelova machines for drawing «Cup» on the end of the rod is not a rejection symptom.

Autogenous cutting is not allowed.

Note. For hot rolled unannealed bars allowed autogenous cutting tips in the amount not exceeding 25 pieces from melting.

2.9. Allowable cut end Squareness, mm for hot rolled bars, and calibrated with special surface finish shall not exceed:

0.1 diameter — for bars with diameter up to 30 mm;

5 mm, for bars with diameter over 30 mm.

Examples of symbols:

Steel hot-rolled round with a diameter of 40 mm, normal precision rolling GOST 2590−88, grades SHKH15, annealed, cold machining OH:

Hot-rolled steel square with sides of square 80 mm, normal precision rolling GOST 2591−88, brand SHKH15SG-IN, unannealed, hot forming AUGE:

Steel hot-rolled round with a diameter of 140 mm, normal precision rolling GOST 2590−88, grades SHKH15, unannealed, hot forming AUGE:

Steel strip with a thickness of 10 mm and a width of 22 mm, normal precision rolling, camber, class 2 GOST 103−76, grades SHKH15, annealed for cold forming XIII:

Steel gauged round, with a diameter of 10 mm, tolerance h11 according to GOST 7417−75, grades SHKH15, for the manufacture of parts by the undercut:

Steel with special surface finish, round, 20 mm diameter, group b, class h11 according to GOST 14955−77, grades SHKH15-IN:

Same brand SHKH15-sh:

.

(Changed edition, Rev. N 1, 4).

3. TECHNICAL REQUIREMENTS

3.1. Bearing steel shall be manufactured in accordance with the requirements of this standard.

3.2. Chemical composition of steel shall conform to the standards specified in table.1.

Table 1

Steel grade	Mass fraction of elements, %
	Carbon	Silicon	Manganese	Chrome	Sulfur	Phosphorus	Nickel	Copper	Nickel+copper
					no more
SHKH15	0,95−1,05	0,17−0,37	0,20−0,40	1,30−1,65	0,02	0,027	0,30	0,25	0,50
SHKH15SG	0,95−1,05	0,40−0,65	0,90−1,20	1,30−1,65	0,02	0,027	0,30	0,25	0,50
SHKH4	0,95−1,05	0,15−0,30	0,15−0,30	0,35−0,50	0,02	0,027	0,30	0,25	0,50
SHKH20SG	0,90−1,00	0,55−0,85	1,40−1,70	1,40−1,70	0,02	0,027	0,30	0,25	0,50

3.2.1. In the steel obtained by electroslag remelting, the mass fraction of sulfur should not exceed 0.01% and phosphorus of 0.025%.

For steel grade SHKH15SG-W section more than 140 mm intended for manufacturing of large bearings, installed suganya limits: mass fraction of manganese — 1,00%-1,20%, chromium — 1,40%-1,65%, silicon — 0,45%-0,65%.

3.2.2. In the smelting of steel in an acid open-hearth furnaces allowed the mass fraction of copper to 0.30%, while preserving the norm of the total mass fraction of copper and Nickel not over 0.50 percent.

3.2.3. The mass fraction of oxygen in the steel should be not more than 0,0015%. The norm of the mass fraction of oxygen is not a rejection symptom before January 1, 2004, Actual inspection results are entered into the document of quality.

(Changed edition, Rev. N 6).

3.2.4. Mass fraction of titanium in the steel should be not more than 0.01%. The norm of the mass fraction of titanium is not rejection symptom before January 1, 2004, Actual inspection results are entered into the document of quality.

(Added, Rev. N 6).

3.3. Hot rolled steel shall be made of annealed or unannealed, and calibrated with special surface finish — annealed.

Steel with special surface finishing calibrated and should not be hard as a result of mechanical surface treatment.

3.4. On the surface of hot-rolled bars and strips designed for hot forming and cold forming are not permitted rolled out the cracks, sunsets, rolled out impurities and bubbles, rolling slivers, and flaw.

Surface defects should be removed. The depth of Stripping shall not exceed:

for rods or bars of diameter or thickness less than 80 mm — half of the limit deviations on size, starting from the actual;

for bars with diameter from 80 to 180 mm limit deviation of the size measured from actual;

for bars with diameter exceeding 180 mm — 5% from nominal size, but not more than 15 mm.

The width of the stripped sections should not be less than five times the depth of them. Cutting defects are not allowed.

Allowed without Stripping defects of mechanical origin (fingerprints, scratches, Rabisha, etc.) to a depth not exceeding half of the limit deviations on size, starting from the actual.

3.5. On the surface of hot-rolled bars and strips intended for cold mechanical processing (turning, milling, etc.), permitted surface defects when their depth does not exceed half of the limit deviations on size, starting from the actual.

3.4, 3.5. (Changed edition, Rev. N 3).

3.6. To steel with special surface finishing In group a defects are not allowed, and the group G is allowed to separate surface defects of mechanical origin with a depth not exceeding half of the maximum deviations in diameter.

On the surface, calibrated rods and coils for the manufacture of parts by disembarkation are not permitted sunsets, scratches, cracks, flat Stripping, remains of scale, roll out bubbles and contamination.

On the surface of the grooved bars intended for the manufacture of parts by the undercut allowed some minor scratches, rabiza, remains of scale, the prints, the gentle Stripping, traces of Stripping abrasive, not exceeding 1% of the diameter.

On the surface of the grooved coils intended for the manufacture of parts by cold heading, the allowed traces of drawing, some minor risks and other defects of a mechanical origin, if the depth does not exceed half of the limit deviations on size.

The depth of defects is determined from the nominal size.

(Changed edition, Rev. N 2).

3.7. Unannealed hot rolled steel with a diameter or thickness up to 60 mm inclusive, calibrated steel with special surface finish that is suitable for forging, stamping, must withstand the test sediment. Hot rolled steel feel hot, and calibrated with special surface finish — cold. In upset samples should not be revealed defects.

3.8. Annealed hot rolled and calibrated steel with special surface finish should have a hardness:

179−207 HB (indentation diameter of 4.5 to 4.2 mm) — for the grade SHKH15,

179−217 HB (indentation diameter and 4.5 to 4.1 mm) — for grades SHKH15SG and SHKH20SG.

3.9. In the macrostructure of finished metal (bars, strips, coils) should not be traces of shrinkage, delamination, birdhouses, bubbles, placenow, inclusions, visible without using the magnifying devices.

Allowed the Central porosity, point heterogeneity, exudation square, not exceeding the limits specified in table.2.

Table 2

The name of the defect	The diameter or thickness of bar, mm	The maximum score for steel
		arc vacuum, acid open-hearth		electroslag remelting
		SHKH4, SHKH15, SHKH15SG	SHKH20SG
Central porosity	From 30 and more	2	2	1
Point heterogeneity	From 30 to 95 incl.	1,5	2,5	1
	100 or more	2	2,5	1
Exudation square	From 30 and more	0,5	0,5	Not allowed

Steel grades SHKH15 and SHKH15SG comes with a normalized magnitude of the defects identified in the products of magnetic method. Methods of control and norms are established by agreement between manufacturer and consumer, and the range of products is the consumer.

3.10. Kink annealed steel should be uniform fine, no burned residues shrinkage and placenow.

3.11. Fracture of steel in the hardened state should be homogeneous, fine-grained, porcelain-like, without burned, the remnants of a shrinkage pipe, placenow, without visible inclusions.

3.12. For hot rolled steel (with annealing and without annealing) depth bezoperatsionnogo layer (ferrite + transition zone) must not exceed per side:

0.25 mm —	for steel diameter or thickness					from	4	to	15 mm
0.40 mm	«	«	«	«	«	St.	15	«	30 mm
0.50 mm	«	«	«	«	«	«	30	«	50 mm
0.60 mm	«	«	«	«	«	«	50	«	70 mm
0.85 mm	«	«	«	«	«	«	70	«	100 mm
1,10 mm	«	«	«	«	«	«	100	«	150 mm incl.

Bars with a diameter or thickness greater than 150 mm in the decarburization is not checked.

3.13. For calibrated steel depth bezoperatsionnogo layer should not exceed 1% of the diameter of the rod.

Decarburization of steel with special surface finishing is not allowed.

3.14. The microstructure of annealed hot rolled steel bars of diameter or thickness up to 85 mm inclusive of steels with special surface finish and gauged steel should consist of uniformly distributed fine pearlite, not exceeding points:

4 for the steel grade SHKH15,

5 steel stamp SHKH15SG and SHKH20SG.

3.15. Carbide mesh in the microstructure of the annealed steel with a diameter or thickness up to 60 mm inclusive is not allowed.

The remains of a carbide mesh should not exceed 3 points.

3.16. Structural banding and carbide segregation should not exceed the limits specified in table.3.

Table 3

The diameter or thickness of bar, mm	Product	The maximum score
		structural poloschatosti		carbide liquation
		SHKH4, SHKH15, SHKH15SG, SHKH20SG	SHKH15-SH, SHKH15SG-SH	SHKH4, SHKH15, SHKH15SG, SHKH20SG	SHKH15-SH SHKH15SG-SH
All sizes	Steel and calibrated with special surface finish	2	2	1	1
Up to 85 incl.	Steel hot rolled annealed	3	2,5	2	1
To 140	Steel hot rolled unannealed	4	3	3	2 +
SV. 140	The same	4D	3,5	3	2

Note. For electroslag remelting of steel with a diameter or thickness of 80 mm or more standards are achieved with the use of omogenizarea heat treatment.

3.17. The steel is checked on the contamination of non-metallic inclusions with maximum points on scales 1, 2, 3 of this standard* and must comply with the standards specified in table.4.
____________________
* Dial 1−8 — see parcel.

Table 4

Method of smelting	The diameter or thickness of bar, mm	Steel	Group number	Score
				oxides	sulfides	globules
				no more
In electric arc furnaces with pumping without vacuum, acid open-hearth furnaces	To 40 incl.	Cold drawn and hot rolled annealed	I	2	2	1,5
		Hot rolled unannealed	II	2,5	2,5	2,0
	More than 40 up to 80 incl.	Cold drawn and hot rolled annealed	III	2,5	2,5	2,0
		Hot rolled unannealed	IV	3	2,5	2,5
	More than 80	Hot rolled unannealed	V	3	3	2,5
Electroslag remelting	Up to 40	-	VI	1	1	1
	More than 40	-	VII	1,5	1,5	1,5

Notes:

1. Excess of norms of globular inclusions to 0.5 points for the rods I, II, III, IV and V groups allowed until 1 January 2004.

2. For bars in all groups except I, allowed separate attacks (the more points specified in table.4):

— for bars of the group III — one attack on one of the types of inclusions, oxides and sulfides shall not exceed 0.5 points, globular inclusions — 1.0 points. The excess of attack on globular inclusions of 0.5 points is not a rejection sign before 1 January 2004 ;

for bars in groups II, IV and V, one lunge no more than 1.0 points for the two types of inclusions. The excess of thrust to 0.5 points is not a rejection sign before 1 January 2004;

for bars in groups VI and VII — single attack by 0.5 points in one sample one type of inclusions.


(Changed edition, Rev. N 2, 5, 6).

3.18. Microporosity steel should not exceed the limits specified in table.6.

Table 6*

_______________
* Table.5. (Deleted. Izm. N 6).

Product	The diameter or thickness of bar, mm	Microporosity in points, not more
Steel with special surface finish and gauged	All sizes	Not allowed
Steel hot rolled annealed	60 and less	The same
The same	SV. 60 to 85	2
Steel electroslag remelting annealed	All sizes	Not allowed
Steel hot rolled unannealed	The same	3

Note. For hot rolled unannealed bars with diameter over 60 mm microporosity more 3rd points allowed by agreement with the consumer.


(Changed edition, Rev. N 6).

3.19. By agreement with the consumer allowed to produce calibrated steel with a phosphated surface.

3.20. On demand of the consumer steel produce:

a) with high requirements for structural poloschatosti (for the untreated steel hot rolled diameter or thickness of wire over 85 to 140 mm, the maximum score structural poloschatosti — 3);

b) increased requirements for macrostructure (with scores less than specified in table.2);

C) with high purity non-metallic inclusions;

g) with controlled hardenability bars with diameter or thickness greater than 28 mm;

d) with high hardenability, which is achieved for steel SHKH15 mass fraction of manganese 0,30%-0,40% and chromium of 1.50%-1,65% and for steel SHKH15SG — manganese 1,05%-1,20% and chromium of 1.50%-1,65%;

e) with the normal carbide mesh bars thickness or diameter in excess of 60 to 85 mm, inclusive;

g) control of macrostructure on longitudinal microtemplate.

Rules on transfers b), C), e), f) establish an agreement between consumer and manufacturer.

4. ACCEPTANCE RULES

4.1. Steel take parties. The party must consist of rods, strips, coils the same bottoms, same size and one mode of heat treatment. The production methods indicated in the accompanying document.

Party steel electroslag remelting must consist of rods, strips, coils of the same size, one mode of heat treatment, obtained from a single source electrodes melting, it melted under a single technology.

Rules of acceptance GOST 7566−94.

(Changed edition, Rev. N 2).

4.2. For quality control of steel set the following sample size:

a) to check size and curvature 10% rods, strips or skeins of the party;

b) to check the surface quality all bars, strips or coils of the party;

C) for chemical analysis — one sample from the melt; the determination of oxygen is carried out on every tenth smelting;

g) to verify compliance with the grade of steel (by sparking or stethoscopes and other non-destructive methods) — all rods, strips or coils of the party;

d) to test for hot and cold draught of three bar or coil of each size in the melt;

e) to test the hardness of the annealed hot-rolled, calibrated steel with special surface finishing:

1−3 of the rod or strip 1 t, but at least 5−10 of the party — with a diameter or thickness up to 30 mm, inclusive;

10% of bars or strips from the party, but at least five pieces from the party — with a diameter or thickness greater than 30 mm;

at least five skeins of the party;

g) to check the macrostructure of two rods or two plates from the party;

h) to verify that no shrinkage on the fracture of bars across the grain steel with special surface finishing calibrated all sizes hot rolled and annealed steel up to 50 mm inclusive — all the bars or coils of the party (at one end); 100% control nondestructive methods steel with special surface finish and calibrated control of the fracture are subjected to two rods from the party. Allowed to conduct inspection ultrasonic inspection at an intermediate workpiece;

and) to check the fracture of bars of annealed steel with a diameter more than 50 mm and the untreated steel of all diameters for tempered samples along the fiber — two rods from the party;

K) to check the depth of the layer besplatnogo — five rods, strips or coils from the party;

l) to check the microstructure (perlite) — five rods, strips or coils from the party;

m) to check carbide mesh carbide segregation, structural poloschatosti — five rods, strips or coils from the party for each type of control;

n) to verify the non-metallic inclusions — six rods, strips or coils from the party;

o) to check the microporosity — six rods, strips or coils from the party;

p) to check the hardenability or two piece from speedo.

(Changed edition, Rev. N 2, 6).

4.3. In case of discrepancy of testing results of any indicator of quality (except for non-metallic inclusions) the requirements of this standard re-examination should be carried out in accordance with GOST 7566−94.

If unsatisfactory inspection results steel non-metallic inclusions can re-inspections should be performed:

the untreated hot-rolled steel in the six new samples;

steel with special surface finishing calibrated and hot rolled annealed — nine new samples taken from randomly selected bars, strips, or coils.

Steel with unsatisfactory results of repeated control non-metallic inclusions can check Positano (for open smelting) or politono (ESR) checking each trap or ingot as a separate party.

5. TEST METHODS

5.1. The sizes of rods, strips and coils, you should check universal measuring devices or templates.

Methods of measuring form deviations of the hire must meet the requirements of GOST 26877−91.

(Changed edition, Rev. N 3).

5.2. Sampling to determine the chemical composition of the steel must be carried out according to GOST 7565−81. Chemical analysis of steel — GOST 28473−90, 12344−2003 GOST, GOST 12345−2001, 12346−78 GOST, GOST 12347−77, 12348−78 GOST, GOST 12350−78, 12352−81 GOST, GOST 12355−78, 12356−81 GOST, GOST 17745−90 or other methods providing the required accuracy.

(Changed edition, Rev. N 2, 6).

5.3. Quality control of the surface should be non-destructive methods.

Allowed to control the surface quality by inspection without the use of magnifying devices. Hot rolled steel should be subjected to pre-etching or bleaching of the rings or snake. The distance between the rings or step snake should not exceed 500 mm.

5.4. Test sediment should be carried out according to GOST 8817−82. When tested on a hot sediment sample with a height equal to two diameters or two thickness of the rod should okazyvatsya to the original height, and when tested on a cold draught up to height.

5.5. The hardness of the annealed steel to be checked on GOST 9012−59 after Stripping bezoperatsionnogo layer from both ends of selected rods, strips and coils. Allowed to check the hardness in the cross section of the samples.

5.6. The macrostructure shall be controlled according to GOST 10243−75. Macrostructure of steel with a diameter or thickness greater than 30 mm should be checked for stained transverse Templeton and fracture, and steel of 30 mm diameter only by fracture.

The absence of shrinkage can be checked for the washers, cut off the two ends of the bar or coil, the magnetic method.

Allowed to check the macrostructure and shrinkage sink non destructive testing according to GOST and GOST 12503−75 21120−75.

The macrostructure of bars with diameter or thickness greater than 120 mm are allowed to control on specimens reforged to the diameter or thickness of 120 mm.

5.7. Fracture control on the specimens cut from one end of the rod, coil, strip.

To obtain the fracture it is necessary to make single or double incision with subsequent breaking away.

(Changed the wording. Izm. N 3).

5.8. Depth bezoperatsionnogo layer should be determined according to GOST 1763−68.

Business-to-consumer may carry out preliminary control of decarburization by the method of sparking.

When the depth control bezoperatsionnogo layers using T samples should be subjected to the annealing temperature (850±10) °C in oil.

After Stripping the surface of bars to a depth corresponding to acceptable standards bezoperatsionnogo layer specified in the claims.3.12 and 3.13, the hardness should be at least 61 HRC.

Depth bezoperatsionnogo layer unannealed steel is allowed to check on the fracture.

If there are differences in the depth bezoperatsionnogo layer test method M.

5.9. Sampling and preparation of samples for evaluation of contamination of steel non-metallic inclusions should be according to GOST 1778−70.

Cut samples must be subjected to a quenching from (850±10) °C with cooling in oil and tempering at 150 °C — 160 °C for 1 h.

Assessment of pollution steel non-metallic inclusions should be made with the increase of 90−110, and the diameter of the field of view of 1.1−1.3 mm.

Evaluation of each cone should be made by comparing its most contaminated places with scales of this standard.

The oxides evaluated by stroke scale N 1, sulphide — scale N 2 and the non-deformable oxides (globules) — N 3, scale.

Silicates evaluated by stroke scale oxides or sulphides and relate to oxide inclusions.

If inclusion could not be assessed in one of two neighbouring points, the evaluation of the intermediate points 0,5; 1,5; 2,5; 3,5, etc.

(Changed edition, Rev. N 2).

5.10. The microstructure (pearlite) hot rolled annealed, calibrated and with special surface finish of the steel should be checked for transverse samples.

Samples for making thin sections must be cut in the form of washers with a thickness of 10−25 mm.

Sections of steel with a diameter or thickness up to 40 mm inclusive must be made across the cross section and diameter or thickness in excess of 40 to 85 mm — carved out of the washers of one quarter section.

Recommended sections to veer into freshly prepared 2% -4% alcohol solution of nitric acid or in a solution of picric acid. The structure of perlite you need to evaluate if you increase 450−600on a scale of # 8.

5.11. Fillet samples, heat treatment and manufacturing of thin sections to assess carbide mesh must be the same as for the evaluation of non-metallic inclusions.

Sections must be poison in 4% strength solution of nitric acid until blackening and distinct identification of carbides.

The remains of a carbide mesh should be evaluated with increasing 450−500at the worst place of the socket by comparison with the standard scale N 4.

A batch of metal it is necessary to estimate by the maximum score estimates of the samples.

When delivered with a normalized carbide steel mesh diameter or thickness 61−85 mm Central zone with a diameter of 25 mm control should not be.

5.12. Structural banding should be evaluated on longitudinal sections.

Cutting, heat treatment and fabrication of thin sections should be made in the same way as for the evaluation of non-metallic inclusions.

Samples taken from the untreated steel should be pre-annealed hardness corresponding to claim 3.8. Samples cut from rods with a diameter of 140 mm and subjected to heat treatment without pre-annealing.

The micro-sections must be poison in freshly prepared 4% alcohol solution of nitric acid. The etching time of 15−20 C.

The evaluation of structural poloschatosti shall be made at 90−110 increaseby comparison with a standard of N scale 5 of this standard.

On each socket it is necessary to estimate the maximum structural banding.

If the evaluation of structural poloschatosti cannot be carried out by comparison with one of the two adjacent standards, it is allowed to estimate intermediate points: 0,5; 1,5; 2,5; 3,5, etc.

The result of the control take the maximum score from the evaluations of the samples.

(Amendment).

5.13. To assess segregation of carbide cutting samples, thermal processing and preparation of thin sections should be made in the same way as for the evaluation of non-metallic inclusions.

Carbide liquation you need to evaluate if you increase 90−110at worst place by comparison with a standard of N scale 6 of this standard.

A batch of metal it is necessary to estimate by the maximum score estimates of the samples.

5.14. Microporosity should be evaluated by viewing the samples made for the control of nonmetallic inclusions.

At each cone with increasing 90−110determine the most microporosity, which were scored by comparison with a standard of N scale 7 of this standard.

If microporosity cannot be evaluated one of the two neighboring points, that allowed assessment of 0,5; 1,5; 2,5; 3,5.

In the steel obtained by electroslag remelting, microporosity should be checked only in the as-delivered profile.

For result control should take the maximum score from the evaluations of the samples.

5.15. Control of hardenability exposed rods of diameter or thickness between 28 mm and more. The control is carried out by the method of mechanical hardening according to GOST 5657−69 and methodology described in Annex 2.

Bars cross-section 50 mm or more needs to be reforged or percutane in the direction of the reference fiber sample with a diameter or thickness of about 30 mm.

5.16. Allowed to assess the structural banding, carbide liquation and carbide mesh on the samples made for the control of nonmetallic inclusions.

5.17. In the manufacture of steel trunks several sizes of sections is permitted to inspect macrostructure, non-metallic inclusions, microporosity (open steel smelting), structural banding and carbide liquation in the profile maximum size, and the results of monitoring be extended to all smaller sizes.

6. LABELING, PACKAGING

6.1. Marking, packing and documentation must comply with the requirements of GOST 7566−94, subject to the following additions.

6.1.1. All bars with a diameter or thickness from 30 to 70 mm inclusive shall be marked on the end rods of diameter or thickness greater than 70 mm on the end.

Note. Allowed by agreement between manufacturer and consumer bars with a diameter or thickness of 70 mm or more marking through sticking paper labels coated with water resistant varnish.

6.1.2. For the coils and rods of diameter or thickness less than 30 mm marking should be applied to append to each bundle labels must also be marked at least three control rods in conjunction with staining them all with green paint.

6.1.3. Steel obtained by electroslag remelting, must have additional marking with letter W, and vacuumed (using a dash).

(Changed edition, Rev. N 1).

6.1.4. Steel with special surface finish should be Packed in sacks, synthetic film or boxes with paper packing. Allowed other packaging that ensures the safety during the transportation of steel from damage and corrosion.

6.2. Steel with special surface finish and gauged for protection against corrosion should be covered with easily removable with grease.

On demand of the consumer steel with special surface finish and gauged lubricant is not covered.

ANNEX 1 (mandatory). UNIFIED ASSORTMENT OF BEARING STEEL, HOT-ROLLED, CALIBRATED AND WITH SPECIAL SURFACE FINISH

ANNEX 1
Mandatory

Table 7

State steel	Diameter of bars, mm
Hot-rolled steel	8; 9; 10; 11; 12; 13; 14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 33; 35; 38; 40; 42; 45; 48; 50; 55; 60; 65; 70; 75; 80; 85; 90; 95; 100; 105; 110; 115; 120; 130; 140; 150; 160; 170; 180; 190; 200; 210; 220; 230; 240; 250
Steel and calibrated with special surface finish	4,0; 4,5; 5,0; 5,5; 6,0; 6,5; 7,0; 8,0; 9,0; 10,0; 11,0; 12,0; 13,0; 14,0; 15,0; 16,0; 17,0; 18,0; 19,0; 20,0; 21,0; 22,0; 23,0; 24,0; 25,0; 26,0; 27,0; 28,0; 29,0; 30,0; 31,0; 32,0; 33,0; 34,0; 35,0; 36,0; 37,0; 38,0; 39,0; 40,0; 41,0; 42,0; 44,0; 45,0; 46,0; 48,0; 49,0; 50,0

(Changed edition, Rev. N 2).

ANNEX 2 (mandatory). CONTROL OF HARDENABILITY OF STEEL GRADES SHKH15 AND SHKH15SG BY THE METHOD OF MECHANICAL HARDENING

ANNEX 2
Mandatory

Test hardenability of steel by end quenching is that one end of a cylindrical sample heated to the quenching temperature, cooled with water in a special installation. After quenching the hardness is measured along the length of the sample from water-cooled end face to the soft head and by interpolation determine the depth of hardenability.

Under the hardenability of steel grades SHKH15 and SHKH15SG understand the depth of penetration of the hardened zone from the cooled end of the sample to the point of having a hardness of 61 HRC.

1. Sampling

1.1. The sample for the testing of steel hardenability should be cylindrical shape with a diameter of (25±0,25) mm and a length of (100±0,5) mm with a shoulder at one end (Fig.1).

Damn.1

1.2. Of the rod with a cross section from 28 to 50 mm the sample machined from center in accordance with the requirements of GOST 7564−97, and bars cross-section 50 mm and more — from samples reforged or perekatnoe on the circle — square size 30mm. the Axis of the specimen and rod must match.

1.3. Samples machined from the annealed steel. Structure of steel after annealing shall conform to the requirements of this standard. Score perlite is specified in the test Protocol.

1.4. At the end of the sample (from the shoulder) should be marked (melting number and sample number).

1.5. To control hardenability select two samples from melting.

2. Equipment and devices

Furnace for heating of samples for quenching.

Heating of the samples under annealing is carried out in a chamber furnace, which should be provided with a temperature difference no more than ±4 °C — volume of the working space and ±3 °C — in time.

The level of stability of maintaining of temperature is achieved by the following:

working space of the furnace is separated from the heating of a special screening a metallic muffle (for example of steel grade H23N18);

the temperature in the furnace is maintained at a predetermined level platinum-rhodium thermocouple with a regulating potentiometer;

the furnace control is carried out by the three-position regulation: «maximum», «normal», «off». To control the working of the thermocouple in the furnace must have additional hole for mounting a control thermocouple, which is connected to a portable potentiometer type PP. The accuracy of working of thermocouple during operation shall be inspected daily by the control thermocouple and portable potentiometer type PP.

Installation for quenching of the sample (Fig.2).

1 — holder; 2 — sample; 3 — nozzle

Damn.2

The installation must comply with the following basic requirements:

the specimen shall be mounted vertically face the surface of the nozzle, the axis of the specimen and the nozzle must match.

the nozzle diameter of (12,5±0,5) mm, height of free water jet above the nozzle (65+5) mm and the distance from the nozzle to the end of the sample (12,5±0,5) mm;

the stream of water before installation sample must be covered with a special plate, which after the installation of the heated sample is shifted in the direction;

the height of the jet in the cooling process, the sample should be constant;

the water should just touch the end of the sample, not washing its cylindrical surface.

Instrument for measuring hardness.

Hardness is determined by Rockwell (HRC) in accordance with the requirements of GOST 9013−59. The hardness of various batches of steel shall be measured at the same hardness and the same diamond cone. The device should be set to measure hardness in the range of 60−65 HRC. Every day before testing samples for hardness the hardenability of the accuracy of the readings should be checked on the standard with hardness 60−65 HRC.

3. Sample preparation

3.1. When heating the end of the sample subject to water cooling, must be protected from oxidation and decarburization. The sample is placed in a steel cylindrical Cup with a lid. End intended for cooling, the sample is put on a graphite plate or a layer of spent graphite. The design and dimensions of glass shown in hell.3.

1 — box; 2 — cover; 3 — sample; 4 — graphite plate

Damn.3

3.2. In the furnace must be heated to no more than two samples in cups that are precisely matched to the design mentioned above. Cups must be installed in the center of the oven on a ceramic stand (the brick) so that the end of the thermocouple was at a distance of not more than 10 mm from the Cup (or between the cups if two of them).

3.3. Set the heating temperature of the sample under annealing should be for steel grade SHKH15 — 850 °C, for steel grade SHKH15SG — 840 °C.

3.4. The heating time of the sample (since landing in the furnace) should be 60 min. the Samples are placed in preheated at 850 °C for 30 min cups.

3.5. The time from the moment of extraction of the sample from the furnace before cooling does not exceed 5 s.

3.6. After extraction of the sample from the oven door must be immediately closed.

3.7. The sample should be under running water until completely cooled (at least 10 min).

3.8. The cooling water temperature should be 10 °C — 20 °C. If the temperature of the water for testing is not possible to keep within the specified limits, the test report and the certificate must be specified the actual temperature of the cooling water.

4. Hardness measurement

4.1. For measuring the hardness along the entire length of the tempered sample is ground off two opposite substantially parallel to the pad at depth of (0,7±0,1) mm.

4.2. Sites should zashlifovyvayutsya with abundant cooling water or a special emulsion on the grinding machine. The roughness of the ground should correspond to GOST 2789−73. Not allowed burn marks, causing structural changes in the metal. It is not allowed to manually track grinding on the sandpaper.

Notes:

1. Revealing burn marks on the pads of the samples after grinding can be produced by the following procedure: the plane polished washed with water (warm) and etched in 5% aqueous solution of nitric acid (according to GOST 4461−77) until then, until the surface becomes black (30−60).

After etching, the surface is washed with warm water and then the sample is immersed for 3 with a 50% aqueous solution of hydrochloric acid (according to GOST 3118−77) and washed with water.

Changes of hardness and structure occurring during the grinding after such treatment, are identified in the form of bright and dark spots.

2. Burn marks obtained by grinding, before the hardness measurement needs to be removed to re-grinding to a depth of 0.1 mm. If after re-sanding burn marks remain, then plane to measure the hardness of produce again.

3. Before measuring hardness of the samples is necessary to remove traces of the emulsion, for which the samples are wiped with gasoline or alcohol.

4. Traces of hardness measurements must be removed prior to measurement on the opposite surface. The Burr marks removed with sandpaper N 3 or N 40 micron.

4.3. For determining hardenability of steel hardness measurements begin at a distance of 1.5 mm from the hardened end face in the axial direction at intervals of 1.5 mm to obtain a hardness less than 61 HRC for steel grades SHKH15 and less than 60 HRC, for steel grade SHKH15SG. Locations of hardness measurements shall be marked on caslifornia the platform using special tools or a pencil with a metal ruler.

4.4. If necessary, re-measure the hardness at the site where the measurements were made, the site must be refaced. Depth of metal removal when re-grinding should be 0.1−0.2 mm. is allowed to produce a new track.

4.5. If the sample cracks or other defects that lead to distortion of results of the hardness measurements, the sample is rejected.

5. Evaluation of test results

5.1. For each pair of points at the same distance from the end face on the opposite two sites, calculate the average hardness value.

5.2. By interpolation, determine the distance from the end of the sample to the point of having a hardness of 61 HRC for steel grades SHKH15 and 60 HRC, for steel grade SHKH15SG.

For example, at a distance of 7.5 mm from the end of the sample, the average hardness of steel grade SHKH15 on measurements from two sides is 63.5 HRC, and at the distance of 9.0 mm — 59,0 HRC.

1) the Difference in hardness of these related points:

63,5 HRC — HRC 59,0 =4,5 HRC.

2) the Difference in hardness points at a distance of 7.5 mm from the end (above the critical) and critical hardness:

63,5 HRC — 61,0 HRC =HRC OF 2.5.

3) Drop the hardness 4.5 HRC occurs on the length of 1.5 mm.

4) Drop the hardness to HRC of 2.5 occurs at the length equal to:

mm.

5) the Hardenability of a given sample is, mm:

7,5+0,83=8,33.

A similar result would be obtained when calculating the position of a point with depth hardenability 61,0 HRC, if made from the points of hardenability is less critical. In this case, you must not add, and subtract the estimated distance corresponding to the gradient of hardness. For the above example the calculation would be as follows:

61,0 HRC — HRC 59,0 =2,0 HRC;

;

P=9.0 mm — 0.67 mm =8,33 mm

Determination of hardenability can be performed by interpolation, and also a graphical way. Sample schedule for calculation given on features.4 and requires no special explanation.

Damn.4

The PARCEL

SCALE N 1. OXIDE INCLUSIONS x100

SCALE N 1

OXIDE INCLUSIONS

SCALE N 2. SULFIDE INCLUSIONS X100

N SCALE 2

SULFIDE INCLUSIONS

SCALE N 3. OXIDE INCLUSIONS non-deformable X100 (GLOBULAR)

N SCALE 3

NON-DEFORMABLE OXIDE INCLUSIONS (GLOBULAR)

N SCALE 4. CARBIDE MESH X500

N SCALE 4

CARBIDE MESH

N SCALE 5. STRUCTURAL BANDING X100

SCALE N 5

STRUCTURAL BANDING

N SCALE 6. N SCALE 6 CARBIDE LIQUATION X100

N SCALE 6

CARBIDE LIQUATION

N SCALE 7. MICROPOROSITY X100

N SCALE 7

MICROPOROSITY

N SCALE 8 X500. THE MICROSTRUCTURE OF ANNEALED STEEL

N SCALE 8
THE MICROSTRUCTURE OF ANNEALED STEEL