TU 14-1-899-74

The Ministry of ferrous metallurgy of the USSR

WIRE COLD DRAWN ALLOY
40KKHNM

SPECIFICATIONS
THAT 14−1-899−74
(instead CMTU 1−188−67)

Sheet 1
THAT 14−1-899−74

These specifications apply to cold drawn wire of precision alloy 40KKHNM for the manufacture of heat-resistant and corrosion-resistant springs.

1. ASSORTMENT

1.1. Wire comes Ø0,5−6,0 mm with a step size of 4 group GOST 2771−57. Acceptable deviation of the diameter according to GOST 2771−57, the precision group ГТ4.

1.2. The roundness of the wire must not exceed half of the limit deviation for diameter.

Note: it is allowed to butt weld the wire to the redistribution, with the exception of the last redistribution. Defects of welds acceptance a sign is not.

2. TECHNICAL REQUIREMENTS

2.1. The chemical composition of the alloy 40KKHNM must match what is specified in GOST 10994−64.

2.2. Wire is supplied in cold-worked condition with a degree of deformation of 25−45%.

For wire diameter less than 0.8 mm the degree of deformation is not specified.

2.3. The surface of the wire is specified in GOST 14118−69.

Sheet 2
THAT 14−1-899−74

2.4. Mechanical properties of wire are tested in the delivery condition in the delivery condition + dispersion hardening at a temperature of 450−500°C for 4 hours.

The value must conform to the standards specified in table 1.

Table 1

Note: Wire with a diameter of more than 2 mm at the inflection is not tested.

3. TEST METHODS, PACKAGING AND LABELLING

3.1. Test methods, packing and marking shall be in accordance with GOST 14118−69.

4. THE ORDER PRICE CALCULATION

4.1. Pricing according to Appendix.

Joined: 26.04.74 G.
Head. the technical Department of TSNIICHM /Kaplan A. S./

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The Annex to THAT 14−1-899−74
(instead CMTU 1−188−67)

PRICING

The wholesale price of x/t wire of steel grade 40KKHNM new THAT calculated the normative-parametric method according to the «regulations», approved by No. 10−15/2935 7/CP-72.

As analog adopted a wire of the same brand for CMTU 1−188−67, the prices of which are approved by Supplement No. 4 to the price list 01−05.

To the wire on the new TU in comparison with the equivalent shall meet the following additional requirements:

The wholesale price of basic wire size ø 4 mm for new THAT is defined by the formula:

CC = (CB ± CC x DF) x (1±PP/100) ± PR (34,8+0,7+0,15) x (1+2/100) TSO — 36.50,
where CB = 34 rubles and 80 kopecks per kg of wire brand of analogue EXT. 4 to prask. 01−05;
TSM = 0 RUB 70 kopecks (2%) — the difference in the price of the metal of a new brand and a base (the difference in price
metal by narrowing the limits for manganese). Foundation: prask. 01−03 p. 403;
Ku = 1.5 factor increase in the difference in the price of the metal of the base and new grades of steel
Annex 2 to the «Position» from 7/12.72, No. 10−15/2935.

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The Annex to THAT 14−1-899−74

PP = 2% for mandatory regulation of the mechanical properties according to Annex No. 1
to the «Position» from 7/12.72, No. 10−15/2935.

On the wire the other the size of the wholesale prices determined based on the base size, with coefficients of correlation of wholesale prices of wire of appropriate dimensions of the brand-analogue placed in the additional 4 to prask. 01−05.

Wholesale price agreed:
Head. Department cost, profitability 16.04.74 G.
and pricing of ICM /VI Chaplanov/