TU 14-131-904-2010

Sheet 2

TU 14-131-904-2010

These technical conditions apply to heat-resistant spring wire made of alloy ХН77ТЮР (ЭИ437Б), intended for the production of springs with an operating temperature of up to 500 °C.

Example of a symbol:

Wire with a diameter of 5.6 mm made of alloy ХН77ТЮР (ЭИ437Б) according to TU 14-131-904-2010.

Wire 5.6 ХН77ТЮР (EI437Б) TU 14-131-904-2010.

1. ASSORTMENT

1.1. Wire is supplied with diameters from 1.0 mm to 5.6 mm.

Wire diameters and maximum diameter deviations must correspond to the data specified in Table 1.

Table 1

Wire diameter, mm	Maximum deviations in diameter, mm	Wire diameter, mm	Maximum deviations in diameter, mm
1.0 1,2 1.4 1.5	±0.02	2,3 2.6 2.9 3.1 3.6 4.1 4.6	-0.08
1.6 1.8 2.0 2.1 2,2	-0.08
		5.1 5.6	-0.09

Note: By agreement of the parties, delivery of wire of other diameters is permitted.

1.2. The ovality of the wire should not exceed half of the maximum deviation in diameter.

Sheet 3

TU 14-131-904-2010

2. TECHNICAL REQUIREMENTS

2.1. The chemical composition of the alloy ХН77ТЮР (ЭИ437Б) must comply with the requirements of GOST 5632.

2.2. The wire is supplied in a work-hardened condition with an etched surface.

2.3. The wire surface must not have cracks, hairlines, rolls, films, or delaminations. Dents, nicks, scratches, ripples are allowed if their depth does not exceed half the maximum deviation in diameter, calculated from the actual size.

2.4. The ultimate tensile strength (σ _in ) of the wire in the delivered condition must be at least 1230 N/mm² (125 kgf/mm²).

2.5. The wire in the delivered condition is tested for winding. In this case, the sample subjected to the test should not have any delamination, cracks, breaks or fractures.

2.6. Wire with a diameter of 3.0 mm or less is tested for bending. The number of bends should be at least 2.

2.7. The surface of wire with a diameter of 1.8 ÷ 5.6 mm in the as-delivered condition is tested for chloride ion content.

The content of chlorine ions on the wire surface is allowed to be no more than 0.2 mg per 2500 mm² of surface area. Actual data is entered into the quality document.

3. ACCEPTANCE RULES AND TEST METHODS

3.1. Acceptance rules and testing methods in accordance with GOST 7566 and GOST 14118 with the following additions.

3.1.1. To determine the ultimate strength, bending tests, winding tests and the presence of chloride ions on the wire surface, 5% of the skeins, but not less than two from the batch, must be selected. For each type of test, one sample must be taken from both ends of each skein from the number selected.

3.1.2. The presence of chlorine ions on the surface is determined in accordance with the methodology attached to these TU.

4. PACKAGING, MARKING, DOCUMENTATION

4.1. Packaging, labeling, and documentation in accordance with GOST 7566 and GOST 14118 with the following additions:

Sheet 4

TU 14-131-904-2010

4.1.1. The wire is supplied without oiling.

4.1.2. The wire is supplied in skeins, each skein of wire must consist of one section of wire. Skeins of wire of the same diameter may be tied into coils. The rows in the skein must not be tangled, the ends of the skein or coil must be neatly laid out and easily found.

4.1.3. The weight of one packaging item must not exceed 80 kg.

5. TRANSPORTATION AND STORAGE

5.1. Transportation of wire must be carried out by all types of transport in conditions that protect it from exposure to moisture, aggressive environments, contamination or damage to the integrity of the packaging.

5.2. The wire must be stored in a dry room in conditions that exclude exposure to moisture and aggressive environments.

REGISTERED: at JSC "Metallurgical Plant "Elektrostal" Acting Head of the Standardization Bureau O.B. Shvyryaeva

Sheet 5

TU 14-131-904-2010

Appendix No. 1

NEPHELOMETRIC METHOD FOR DETERMINING CHLORINE IONS

The nephelometric reaction for the determination of chlorine ions is based on the precipitation of chloride by silver nitrate.

AqNO₃ + NaCl → AqCl + NaNO₃

Silver chloride is released as a fine-grained, stable turbidity.

A solution with a titer equal to 0.01 mg of chloride ion is taken as a titrated solution.

1. SAMPLING METHOD

1.1. The sizes of samples depending on the wire diameter are indicated in the table.

Table

Wire diameter, mm	Sample length, mm
1.8	450
2.0 2.1 2,2 2,3	400
2.6 2.9	320
3.1	270
3.6	230
4.1	200
4.6	180
5.1	160
5.6	150

1.2. Samples should be cut into 50-60 mm long pieces and placed in bags with the wire's passport data written on them. When cutting samples, measures should be taken to prevent their contamination with other chemicals and oils.

Sheet 6

TU 14-131-904-2010

2. EQUIPMENT AND REAGENTS

2.1. Volumetric flasks of the same glass with a capacity of 50 ml according to GOST 1770.

2.2. Flasks with a capacity of 250 ml according to GOST 25336.

2.3. AqNO₃ 0.1N solution.

2.4. HNO₃ density 1.4 g/cm³.

2.5. Standard KCl solution, 1 ml of which corresponds to 0.01 mg of chloride ions (0.2103 g of recrystallized potassium chloride is dissolved in a 1 liter measuring flask, 10 ml of alkvota is taken, and brought up to the mark with distilled water in a 100 ml measuring flask).

Note: 56.4 ml of 0.05N KCl solution in a 1 liter measuring flask

3. PREPARATION FOR THE TEST

3.1. The standard scale for nephelometric determination of chlorine ions is prepared in 50 ml volumetric flasks.

3.2. Take 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 ml of KCl solution with a titer of 0.01 mg of chloride ions in 50 ml volumetric flasks.

3.3. Add 10-15 ml of distilled water.

3.4. Add 5-6 drops of HNO₃ 1.4 g/cm³ and 1 ml of 0.1N AqNO₃.

3.5. The solutions are brought to the mark with distilled water and mixed.

4. CONDUCTING THE TEST

4.1. Place the pieces of wire in a 250 ml flask, add 40 ml of distilled water, close the flask and boil for 15-20 minutes.

4.2. After boiling, cool the solution and pour it into a 50 ml measuring flask, rinse the walls of the flask with a small amount of distilled water and pour it into the same 50 ml flask.

4.3. Add 5-6 drops of HNO₃ with a density of 1.4 g/cm³ and 1 ml of a 0.1N solution of AqNO₃.

4.4. The solution is brought up to the mark with distilled water and mixed.

4.5. All the above operations are carried out in parallel on a blank sample.

Sheet 7

TU 14-131-904-2010

5. PROCESSING RESULTS

5.1 The sample is compared with a blank. The absence of turbidity indicates the absence of chlorine ions in the solution.

5.2. The quantitative content of chlorine ions on the surface of the wire is determined by comparing the sample with the standard scale (section 3) containing different amounts of silver chloride.