SU556194A1 - Steel - Google Patents

Description

The invention relates to the field of ferrous metallurgy, in part to the field of protection of metals from corrosion cracking in hydrogen sulfide solutions.

Lime steel, resistant to cracking in solutions of hydrogen sulfide, of the following composition, wt. %:

Carbon

0.17-0.2

Chrome 1.0 -1.5 0.1 -0.15

Titanium

Cremium -0.4

0.3 -0.15 0.1

Waiadi

Manganese 0.2-0.5 0.2–0.5 Molybdenum Rare Earth

0.08-0.1

metals Else. Iron A disadvantage of the well-known steel is that it contains expensive metals - molybdenum and titanium, which limits its massive use in industry.

Lime also steel of the following composition, weight. %:

Carbon0.08-0.2

Chrome 0.6 -1.2

Aluminum0.15 -0.6

Creme 0.10 -0.5

Manganese 0.6 -1.2

Molybdenum or wadiol 0.005-0.15

2

In addition, steel may contain cerium in an amount of 0.05-0.01 wt. %

The lack of lime in steel is that it has a low resistance against corrosion cracking in environments containing hydrogen sulfide. So, when tested in a solution saturated with hydrogen sulfide for 140 h, the limiting rate at which the specimens were not destroyed was 40-45 kg / mm.

It is an invention to increase the resistance of steel against corrosion and corrosion cracking in environments containing hydrogen sulfide.

This goal is achieved by the fact that the decomposed steel contains comioeites in the following

ratio, weight. %:

0.17-0.2

Carbon

Chrome 1 -2 0.5 -0.8

Silicon 0.3-0.8

Vanadium 0.1-0.3

Aluminum Rare Earth

0.08-0.1

Metals Ostal Iron

Below are specific formulations of the steel studied, weight. %:

II

I

0.17

0.2

1.0 2.0 0.8

0.5

0.3 0.8

0.1 0.3

0.08

Lin metals 0.1

The rest |

Example. Test

for corrosion cracking, the solution was carried out in solution, saturation with hydrogen sulfide, which partially simulated water condensates of gas fields.

Testing of these samples with a diameter of 5 mm and a uniaxial stress state. Has the lowest voltage been determined at which samples do not crack in 140 hours of testing?

Heat treatment of the samples consisted of quenching into water from a temperature of 960 ° C and drying at 700 ° C.

As a result of tests, it was established that the yield strength of steel of composition I is equal to 63 kg / mm, composition II - 70 kg / mm-; The ultimate stress of stalp of both ravio compositions is 60 kg / mm.

The proposed steel can be used for the manufacture of combi-compressor pipes and couplings, as well as casing pipes used in the extraction of gas with impurities of sulfur.

Claims (2)

Invention Formula Steel containing carbon, chromium, silicon, vanadium, aluminum, rare-earth metals and iron, characterized in that, with its superior resistance to corrosion cracking in environments containing hydrogen sulfide, it contains compounds in the following ratio, weight. %: Carbon 0.17-0.2 Chrome1 -2 Silicon 0.5-0.8 Vanadium0.3 -0.8 Aluminum0.1 -0.3 Rare earth metals0.08-0.1 IronErest Sources of information that are irrelevant to the NRN exertize: CW St. USSR A1 427088, cl. C 22c 39/14, 1972. 2. Iateit Great Britain H1 No. 791884, cl. 72 A, 1958.