SU1397538A1 - Steel - Google Patents

Abstract

The invention relates to steels for the manufacture of oil country tubular goods. The purpose of the invention is to increase the hardenability, corrosion resistance and resistance to cracking of steel, which is achieved by the addition of copper, nickel and steel to steel. Steel has the following chemical composition, wt.% 1 carbon 0,25-0,35; manganese 0.8-1.6; silicon 0.4-0.9; chromium 0.3-0.6; copper 0.1-0.5; Nickel 1.0-0.5; vanadium 0.04-0.15; nitrogen 0,008-0,02; aluminum 0.005-0.015; calcium 0.001-0.01; iron else. The tensile strength of steel is 98.1-112 kgf / mm. The time of formation of cracks at the site of bending of prestressed specimens in a boiling 20% solution of aluminum nitrate after quenching and tempering 720-792 hours 4 of the Table. S (I

Description

with with joint venture

her ace

 The invention relates to metallurgy, in particular, to steel for the manufacture of petroleum pipes.

The purpose of the invention is to improve the quality, corrosion resistance and burring resistance of the proposed steel.

The chemical composition of the studied melts of the proposed (2-4) and known (1) steels is given in Table 1, The results of determining the hardenability of the studied melts of the proposed steel (3-5), steel 38ХНМ (1) and known steel ) are given in Table 2, and their mechanical properties are given in Table 2; Table 3 shows the time of cracking at the place of bend.

Steel containing carbon, marz, silicon, chromium, vanadium, nitrogen aluminum, iron, characterized in that, for the purpose of higher

prestressed specimens

and a boiling 20% solution of nitrous oxide-20 ™ hardenability, corrosive

aluminum logo

The achievable level of mechanical properties of the proposed steel allows it to be used for the manufacture of oil-grade pipes instead of steel 25

38HNM

Production of petroleum sart pipes, ment of the proposed steel instead of

resistance and resistance to crack formation, it additionally contains copper, nickel, calcium with the following ratio of components, wt%:

Carbon

Manganese

Silicon

Chromium

0.25-0.35

0.8-1.6

0.4-0.9

0.3-0.6

I

known by doping with nickel, copper, calcium in nitride vanadium hardening, will eliminate defects in stress cracks and simplify the technology for the production of pipes and tube blanks. Pipes and pipe billets of famous steel due

Crackiness tendencies are cooled in special furnaces or wells, from cooled steel they are cooled in air.

Known steel products pass normalization with tempering, of the proposed steel - only normalization

The technology of production of pipes from the proposed steel reduces energy costs and cost.

Claims (1)

Invention Formula Steel containing carbon, manganese, silicon, chromium, vanadium, nitrogen, aluminum, iron, characterized in that, for the purpose of higher hardenability, corrosion resistance and resistance to cracking, it additionally contains copper, nickel, calcium with the following ratio of components, wt.%: five 0 five Carbon Manganese Silicon Chromium Vanadium Nitrogen Aluminum Copper Nickel Calcium Iron 0.25-0.35 0.8-1.6 0.4-0.9 0.3-0.6 0.04-0.15 0,008-0,020 0,005-0,015 0.1-0.5 0.1-0.5 0.001-0.01 Rest Table 1 Continued table. i Table3 Known steel 162, 200 We offer steel Continuation of table 3 Table 4