SU834227A1 - Steel - Google Patents

Description

(54) STEEL

one

The invention relates to metallurgy, in particular to steel, which has an increased corrosion resistance to general corrosion and sulphide cracking and is used in the manufacture of pipes operating in active media containing, for example, sulfur compounds.

Known steel l, containing, wt.%:

0.32-0.40 carbon

Manganese 1.50-1.80

Silicon 0.4-0.7

Sulfur Up to 0.035

Phosphorus Up to 0.035

Iron Else

However, this standard does not have sufficient corrosion resistance.

Closest to the proposed technical essence and the achieved effect is steel 2, containing, wt.%:

Carbon 0.20-0.45

Manganese 0.60-1.40

Silicon 0.80-2.50

Chrome To 1, O

Molybdenum Up to 0.50.

Vanadium To 0.50

Nickel To 0.50

Aluminum Up to 0.03

Sulfur Up to 0.05

Phosphorus Up to 0.07

Iron Else

Known steel has a sufficiently high level of mechanical strength with insufficient corrosion resistance and resistance to stress corrosion cracking. Moreover, this high level of mechanical loyalty can only be achieved as a result. tatu quenching in water with subsequent release, which significantly increases the cost of manufactured products.

The purpose of the invention is to improve corrosion resistance and corrosion cracking resistance of steel.

The goal is achieved by those. that steel containing carbon, manganese, silicon, chromium, aluminum, phosphorus and iron additionally contains copper, titanium, cerium and antimony in the following ratio of components, wt.%:

Carbon 0.12-0.18

five

Manganese: 1.5-2.0

Silicon 1.3-1.5

Chrome 0.1-0.5

Aluminum 0.1-0.5

Phosphorus 0.03-0.1

0

0.1-0.5

0.1-0.2

0.01-0.05

0.01-0.05

Rest

Primer p. Make samples of the proposed steel, obtained in an induction furnace, two compositions, the first of which contains, wt%: carbon 0.12; manganese 1.5, silicon 1,3; chromium 0.1; copper 0.1, titanium 0.1 / aluminum 0.1; phosphorus 0 03, cerium 0.01, antimony 0.01; iron the rest, and the second contains, wt%: carbon 0,18; manganese 2.0) silicon 1.5; chromium 0.5; copper 0.5; titanium 0.2; aluminum 0.5; phosphorus 0, cerium 0.05, antimony 0.05; iron else.

Samples are also made of the known steel of two compositions, the first one containing, wt%: carbon 0.2; manganese 0.6, silicon 0.8, chromium 0.1; molybdenum 0.05, vanadium 0.05; Nickel 0.05, aluminum 0.01 (sulfur 0.01, phosphorus 0.01, iron ocTSLnbHoe, and the second - wt.% g carbon 0.45; manganese 1.4; silicon 2.5, chromium 1.0, molybdenum 0.5, vanadium 0.5, nickel0.5, aluminum 0.03, sulfur 0.05, phos, form 0.07 / octagonal iron.

We offer:

52.6

67.1 Results of tests for corrosion resistance in a salt-saturated hydrogen sulfide-containing medium 1 samples

We offer:

1 Same

The samples were tested in medium 1 (a saline solution of oil and gas regions of the Kuibyshev and Orenburg fields with hydrogen sulfide manifestation) having an ionic composition, g / l; HCO 0.329, AOR 1.393 / ce 158.11; , 459; Ca 5.210 (Na + K) 94.595; HzS beats. weight. 1.168 g / cm, pH 6.3, and in medium 2 (a solution imitating aqueous salt-containing solutions of oil and gas fields in the Azerbaijan SSR, Grozny region with hydrogen sulfide) j containing 3% NaCI,

3000 mg / l HIS and 10% of it.

In medium 1 samples of 2 X 8 X are tested. 100 mm by weight method for general corrosion, in medium 2 - cylindrical samples 120 mm long, 10 mm in diameter with a stress concentrator (notch depth 1 mm, radius at the crack tip 0.1 mm ) for RESISTANCE to sulfide cracking at a voltage of 50 kgf / mm (0.9b) Before testing, the samples are subjected to normalization at 860 ° C, followed by tempering at.

The results of mechanical testing of samples made from the proposed and known steel are given in table. 1 .. Ie and l and c

68,8

28.0

1.53 Corrosion is uniform in

1.38 the entire sample surface

2.06 Corrosi wears a local

2.19 character, there are traces of pitting 100 x 8 x 2 mm, made from the proposed and known steel, are given in table. 2.,. , .. Table 2

Thus, with the same mechanical properties (Table 1) of the proposed and known steel, the corrosion rate (Table 2) in the proposed-steel medium 1 is 1, H81, 53, while the known steel is 2.06- 2.19. With

We offer:

Known:

 one .

from the data table. 3, it can be seen that samples made from known steel are destroyed due to sulfide cracking after an average of 190 hours, while samples made from the proposed steel withstand the test for 300 hours.

Claims (2)

The steel we offer is technologically advanced in smelting, well processed. In addition, it is characterized by high resistance to both general corrosion and sulphide cracking. in salt solutions containing hydrogen sulfide. Claims containing carbon, manganese, silicon, chromium alumna, phosphorus and iron, characterized in that, in order to increase the corrosion resistance and resistance This is carried out by parsley testing on twenty samples of each composition with a test duration of 50 hours. The test results - cylindrical samples in medium 2 are given in table. 3 .. Table3 300 Do not destroy. 300 Also Sample rupture Also corrosion cracking she 0 additionally contains copper, titanium, cerium and antimony in the following correlation of components, wt.%; 0.12-0.18 Carbon 1.5-2.0 Manganese five 1.3-1.5 Silicon 0.1-0.5 Chromium 0.1-0.5 Aluminum 0.03-0.1 Phosphorus 0.1-0.5 Copper 0 0.1-0.2 Titanium 0.01-0.05 Cerium 0.01-0.05 Antimony Rest Iron Sources of information taken into account in the examination 1. Steel is alloyed, structural, brands and technical requirements GOST 4543-71. Click here for the brand 36Г2С. 2. The patent of France 2107804, cl. Kommersant 21 V 17/00, C 22 C 38/00, published. 1972.