SA518400073B1 - Steel for hydrogen sulfide stress corrosion cracking resistant martensitic stainless steel oil casing pipe, and oil casing pipe and production method therefor - Google Patents

Abstract

A steel for a hydrogen sulfide stress corrosion cracking cracking resistant martensitic stainless steel oil casing pipe, and an oil casing pipe and production method therefor. The steel comprises, in mass percent, chemical elements: 0˂C≤0.05%, Si: 0.1-0.2%, Mn: 0.20-1.0%, Cr: 11.0-14.0%, Ni: 4.0-7.0%, Mo: 1.5-2.5%, N: 0.001-0.10%, V: 0.03-0.6%, and Al: 0.01-0.04%, with the balance being Fe and other inevitable impurities.

Description

faa resistance to fracturing martensitic steel oil casing pipe that does not bial from Bala and hydrogen sulfide stress corrosion and oil casing pipe and method for its production

STEEL FOR HYDROGEN SULFIDE STRESS CORROSION CRACKING

RESISTANT MARTENSITIC STAINLESS STEEL OIL CASING PIPE, AND

OIL CASING PIPE AND PRODUCTION METHOD THEREFOR

Full description Background of the invention The present disclosure relates to a metal material, an oil casing pipe, and a method for its manufacture. In particular, it relates to a steel material ball for a martensitic stainless steel oil casing tube and an oil casing tube and a method for its manufacture. With the consumption of easily accessible energy resources; Exploitation is concentrated more and more in the environment with high temperature and high pressure as well as the environment with high corrosion resulting from hydrogen sulfide (11:5) which has a partial pressure of up to 0.01 MPa and carbon dioxide carbon dioxide (0©) and chloride ion (CI) chloride jon and the like that co-exist at high concentrations of 0. In addition, since many oil and gas sources are located in cold regions, the air temperature It can reach -20m or even less Lovie Operations are carried out in winter In such an environment high alloy products such as super martensitic stainless steel and the like need as Ob dele It meets requirements for corrosion resistance.Although the stainless steel super martensitic steel core exhibits excellent corrosion resistance5 in environments with Alle temperature and high concentrations of carbon dioxide and chloride ion, it is also usable in environments containing non-hydrogen sulfide Ltd. The patent application discloses a Chinese No. 1729306 (published on February 1, 2006 under the title “HIGH STRENGTH MARTENSITIC STAINLESS STEEL EXCELLENT IN CARBON DIOXIDE GAS CORROSION RESISTANCE AND SULFIDE STRESS CORROSION” CRACKING RESISTANCE 20) Resistance to 860 MPa or higher and includes chemical elements 400 7 by mass: (C) carbon 0.005 - 70.04 (Si) silicon 70.5

or less Manganese: (Mn) Manganese 3.0-0.1 7 or less Phosphorus: (P) Phosphorus 0.4 7 or J Sulfur (5): 70.01 or less Chromium (Cr) Chromium 715-10 Nickel

RT): 4.0 Z8- ¢ Molybdenum: (Mo) Molybdenum 5.0-2.8 Aluminium: 70.10-1 and Nitrogen (00): 70.07 or Jal with an equal amount of iron Iron 5 050 and with the presence of contaminants it is not possible to edad, as the chemical elements satisfy the following equation Molidnum > 0.89-3 for Silicon + 32.2 Creon”; And where the shiny structure Hell consists mainly of tempered martensite carbides that are deposited during the tempering process, and intermetallic compounds from the Laves phase, where a “phase” and the like are deposited. This is precisely done during the steel quenching process.

0 This type of core is characterized by its Alle resistance, however it is used at hydrogen sulfide pressures of up to 0.003 MJIS less. China Patent Application No. 1582342 (published on February 16, 2005 under the title “MARTENSITIC STAINLESS STEEL”) discloses a non-corrosive martensitic steel that includes the following 7 chemical elements by mass: Creon: 70.1-0.01” chromium: L159 50

Tetrogen: 0.1# or less; Whereas, the amount of caride present in the austenitic grain in the pulp is 0.5 7 (by volume) or less. This type of lial has an economic advantage over many other types of martensitic steels and also has good resistance to carbon dioxide corrosion however it is used with hydrogen sulfide at a partial pressure of 0.0003 MPa.

0 in light of the above; It is desirable to provide a material of lal for the oil casing tube and the oil casing tube it is made of and the method of manufacturing it as the oil casing tube can be used in crude oil or natural gas wells which have a strong JB medium where hydrogen sulfide is At a partial pressure of about 0.01 MPa, carbon dioxide, chloride ions and the like are co-existing at high concentrations. Furthermore it;

5. The oil casing pipe can meet the relevant requirements on corrosion resistance and mechanical properties in this medium.

General description of the invention

One of the objects of the present invention involves a core material for a casing tube of (Glial) martensitic

JST resistor induced by hydrogen sulfide pressure corrosion. It is a packaging tube

The oil from the martensitic stainless steel, which is resistant to fracturing caused by corrosion by hydrogen sulfide pressure, can be made from the oil core, as the oil casing tube can be used in oil wells.

Crude oil or natural gas that has a strong corrosive medium in which hydrogen sulfide is at pressure

Partial up to about 0.01 MPa, carbon dioxide, chloride ion and the like, which

be present in high concentrations. Furthermore it; The oil casing tube can satisfy

Relevant requirements for corrosion resistance and mechanical properties in this medium.

lady 0 For the previous purpose of the current disclosure, the steel for the oil casing tube was provided from the stainless steel steel, and this material is resistant to fracturing and corrosion by hydrogen sulfide stress, and it includes the following chemical elements 7 by mass: 0Greon < 70.05; Silicon: 70.2-0.1¢ Manganese: 71.0-0.20 » Chromium: 7214.0-11.0 » Nickel: 77.0-4.0 » Molyadium: 72.515; nitrogen: 70.10-0.001; Vanadium:(V) Vanadium 70.6-0.03 and Aluminum: 7.0.04-0.01 with

5 Equilibrium amount of sale iron and irreplaceable waste. In this technical solution the non-avoidable waste is mainly sulfur; Phosphorus and oxygen (0). Sly the previous objective of the current disclosure is achieved », the inventors have conducted extensive research on the effects of the metallographical structure and hardness of the martensitic steel

0 that does not rust and the special cases of heat treatment of the steel to resist corrosion fracturing from the sulfide stress of the steel. As a result, it was discovered that the process of quenching the core results in a small amount of martensitic, which can be converted into reversed austenite by reducing the temperature for the second metal quenching procedure, as the reversed austenite is formed at a lower temperature and is more bls. so that less

5. The hardness of the core (possibly to 27 HRC or less) and thus the fracturing resistance of the corrosion and sulphide stress of the steel in a hydrogen sulfide medium is ensured at

Partial pressure of about 0.01 Lae Pa. Additionally or in addition to vanadium (preferably to satisfy vanadium: (Creon+Nitrogen) = 2:1 to 8:1 where vanadium, carbon, and nitrogen represent the mass percent of the corresponding elements, respectively) lly allows the precipitation of vanadium Vanadium carbonitride during the process of quenching the core, which weakens the role of carbon and nitrogen atoms that affect the formation of interstitial atoms in the crystal structure, and thus the impact hardness is improved at -20 m. The invention was achieved based on previous results. The different chemical elements in the sale of the oil casing tube of the martensitic steel that does not rust and is resistant to cracking by hydrogen sulfide stress corrosion according to the present disclosure is mainly designed according to the following principles: The martensitic steel that does not rust. The increased carbon content results in an increase in the percentage of astonite curing 2050120 in the faa core at high temperatures; in turn; The martensite is obtained at room temperature so that the resistivity is increased. Although it; The increased amount of Creon content can even out the JS resistance as well as the hardness of 5 of the stainless steel. To ensure the required strength, it is preferable that the mass percentage for Creon be of 70.003 or more. Although it; And when the percentage of carbon is 70.05 or “SI,” the hardness and corrosion resistance tend to decrease. Silicon: Silicon is an important deoxidizer in the preparation of steel. However; In the stainless steel, there is a high content of chromium and the formation of silicon has a risk of 0 in improving the formation of the “ferrite” and “ferrite” phases. The “and ferrite” phases have a negative effect on both hardness and corrosion resistance on the stainless steel. Next; The mass percentage of silicone is limited to the range of 0.2-0.1 7# by weight. Manganese: Manganese can increase the resistance of stainless steel. According to the disclosure; The mass percentage of manganese is not less than 0.2 7 in order to ensure the required strength 5 of the casing pipe is reached. Although it; If the mass percentage of manganese is more than 1.0

#; It reduces hardness. Thus the mass percentage of manganese is limited to the range of 0.2 -71.0; Thanks from 70.5-0.2 wt. Chrome: Chrome is an important component of stainless steels for improved corrosion resistance. The addition of chrome allows the formation of a corrosion-resistant passivation film on 1 steel surfaces that do not rust even in air. 1. Provides an oil casing tube with increased corrosion resistance to carbon dioxide in a high-temperature medium. In order to achieve JS resistance at a temperature of 150 °C or el, the mass percentage of chromium in the stainless steel is limited to not less than 711.0 according to the present disclosure. On the other hand if the mass percentage of chromium is greater than 14.0 off there will be an increased risk of precipitation of 0 ferrite which has a negative effect on the hot workability and corrosion resistance of the product. Next; The mass percentage of chromium is limited to the range of 11.0 -714.0 0" by weight of 11.5-713.5 by weight. Nickel: Nickel extends the austenitic region and also improves the corrosion resistance and hardness of stainless steel, particularly the resistance to fracturing and stress corrosion at high temperatures. In order to achieve this effect, the mass percentage of nickel is limited to not less than 74.0. Although it; If the mass percentage of nickel increases; which is an ab alloy element for 77 in the present disclosure; OB phase 1 of the austenitic phase will be formed in that structure. The resistance of the austenitic phase cannot be controlled by the Malley temperature treatment, so the resistance is reduced. And therefore; The 0 mass percent of nickel is limited to the range of 4.0 -77.0; Thanks from 4.5- 5 wt. Molybdenum: Molybdenum is a special element for resistance to corrosion and pitting of the chloride ion of stainless steel, especially in the medium at a temperature of 150 °C or higher. The mass percentage of molybdenum in the present disclosure shall be limited to not less than 1.5 7. Notwithstanding 5 . of this; And if the gill percentage by mass of molybdenum, which is a metal element “ali element”, exceeds 2.5 7 in the current disclosure, then a relatively large amount of ferrite will be formed.

formed, which has a negative impact on the hot workability and corrosion resistance of the product. And therefore; The mass percentage of molybdenum is limited to its range of 1.5 -72.5; Preferably from 72.3-1.8 by weight. Nitrogen: Nitrogen is an ingredient that improves the corrosion and pitting resistance of stainless steels. Meanwhile, in the form of a caustenite-forming element, nitrogen can increase the ratio of martensitic in the stainless steel of the current detection Ally, in turn, improving the resistance of the stainless steel. In order to achieve this all, the mass percentage of nitrogen in the present disclosure shall be limited to not less than 20.001. However; If the mass percentage of nitrogen is more than 70.10 nitrides 0 tend to form as the hardness is reduced. Thus, the mass percentage of nitrogen is limited to the range of 0.001-70.10 by weight. Vanadium: Vanadium is an important microalloy element. In general; The crystals can be purified by the stabilization effect from the precipitated kreonitrides precipitated carbonitrides thus improving resistance. Thus, it was discovered by the inventors that the addition of 5 vanadium allows the precipitation of vanadium carbonitrides during the quenching of the steel, and thus the role of carbon and nitrogen is strengthened, which affects the form of atoms in the crystalline structure in the steel and reduces the hardness of the steel and improves the effect of hardness at low temperatures ( like -20 m). In order for this to be achieved lil) it is necessary that the mass percent of vanadium be determined not to be less than 70.03 ey side GAY If the mass percent of vanadium is more than 0.6 J 0 the hardness will decrease. Aluminum: Aluminum is added in the form of a deoxidizer during the smelting process in order to achieve deoxidation; the mass percentage of aluminum is limited to not less than 20.01 Jeg though cell if the mass percentage of aluminum is more than 70.04; It reduces hardness. Thus, the mass percentage of aluminum is limited to the range of 5 70.04-0.01 by weight.

Oxygen: Oxygen is an unavoidable waste product. It is present in the form of Ally oxides which have a negative effect on the hot workability, impact toughness and JST resistance of the steel. And therefore; The mass percentage of oxygen is limited to the respective range of 70.0004 or less.

Phosphorus: Phosphorus is an unavoidable contaminant and is a harmful element which impairs the corrosion resistance of carbon dioxide at high temperatures and has a negative effect on hot workability. If the mass percentage of phosphorus is more than 70.03, the corrosion resistance will not meet the requirements of the high temperature medium. And therefore; The mass percent of phosphorus is limited to the range of 0.03 7 or less and a diag of 70.015 or less.

0 Sulfur: Sulfur is an unavoidable waste product. It is detrimental to hot workability and has a negative effect on impact toughness. if the sulfur content is more than 70.01; The pipe from lial cannot be manufactured in the normal way. Thus, the ASH percentage of sulfur is limited to the specific range of 70.01 or less by virtue of 70.005 or less. The stainless steel lial martensini oil casing is resistant to AST breakage resulting from

5 on hydrogen sulfide stress and it can be made from stainless steel based on previous models according to the current disclosure. Said oil casing can be used in wells, in crude oil or in natural gas containing highly corrosive media where hydrogen sulfide is at a partial pressure of about 0.01 MPa and carbon dioxide, chloride ion and the like are co-existing at high concentrations. in addition to; The oil casing tube

0 JST exhibits superior fracture resistance to sulfide stress and is also resistant to high temperature corrosion from carbon dioxide and chlorine ions and has excellent impact toughness in low temperature media. The oil casing also has a resistance of 95 ksi. It can meet relevant requirements on corrosion resistance and mechanical properties.

5 In addition, the stainless steel martensini oil casing pipe of the present disclosure satisfies the following relationship for vanadium: (Creon+N) = 2:1 to 8:1; Where is vanadium based

and Creon and Nitrogen representing the mass percentage of the corresponding elements in the order (Ae) way JB) when the vanadium content is 0.1 7 and the vanadium dad in the formula is 0.1 as well as 0.001); With the aim of achieving a better effect of lack of rigidity as described above. It is preferable in the oil packing tube of lial) which does not repel martensine according to the present discovery that

Mn being 0.02 J0.5-unig in the oil casing tube of bial) which does not repel martensine according to the present discovery to be .7003 Creon < 70.05. Another objective of the present disclosure is to provide a casing tube of oil where a casing tube is

0 Oil has been used in oil, gas or natural gas wells comprising a highly corrosive medium where hydrogen sulfide is at a pressure (ia) of up to 0.01 MPa and where carbon dioxide, chloride ion and the like are co-existing at the temperature concentrations and where the oil casing pipe meets the relevant requirements of corrosion resistance and mechanical properties in the said medium.

Tada 5 For the previous purpose of the current disclosure, an oil casing tube, which was made of stainless steel, was provided for an oil casing tube made of martensitic steel that does not rust according to any of the previous models. Moreover, the oil casing tube of the present disclosure yields a strength higher than 655 MPa and is able to resist fracturing corrosion caused by hydrogen sulfide stress in the embedding medium.

0 on hydrogen sulfide which has a partial pressure of 0.01 MPa. Also, the oil casing tube of the detection Mall produces a strength higher than 655 MPa and ability to resist fracturing stress corrosion of hydrogen sulfide in hydrogen sulfide containing medium having a partial pressure of up to 0.01 MPa and low temperature impact toughness energy. Greater than 100 Joules at -20m.

5 A further objective of the present invention involves providing a method for manufacturing the oil casing tube described above.

According to the previous objective of the current disclosure, a manufacturing method for the oil casing tube was provided according to any of the previous models, and this method includes the following steps in the order shown: (1) manufacturing an airtight tube ¢pipe blank 2) rolling the tube airtight in order to reach Ce of seamless steel pipe 5 (3) heating the seamless steel pipe according to the following steps: (13) quenching the 'martensitic structure' (b) first metal quenching: heating the seamless steel pipe to a temperature of 71 for the first quenching being 11 of 670-600°C; 0 (3C) for the second metal quenching; for a second metal quenching of 72 being 2--71 40°C. of the oil casing tube from the present disclosure; the traditional smelting process can be used using “for example” JU transformer, electric furnace, vacuum induction furnace and the like in step (1) and in the process such as casting Continuous casting, alloying, cingot cogging etc Use it to prepare the crude sample from the airtight tube. In step (2), a Mannesmann pipe-rolling mill can be used to roll the tightly sealed tube into a stainless steel tube of a specified size. The first quenching step (3b) aims to ensure that the stainless steel tube has super low temperature impact toughness. After the first watering 0 operation; The sale inverted austenite is formed at the grain boundaries of the martensitic plate where a portion of the inverted austenite undergoes a martensine transformation during cooling as a result of the relatively high temperature at which the inverse austenite is formed so that the martensitic is formed. The second quenching step (3c) helps in converting the secondary martensitic in the first steel quenching process into reverse austenite and thus reduces the sale hardness and improves the hardness 5 and fracturing resistance resulting from the corrosion of alga (sulphide) in hydrogen sulfide media.

Further, according to the manufacturing method of the oil casing pipe from the present disclosure and in step (13), the seamless steel pipe is heated to a temperature of AC3 or higher for quenching and then cooled to a temperature of 100 °C. In the previous embodiment, if the heating is carried out at a temperature less than AC3, the non-rusting core of the austenite cannot be treated with austenes sufficiently, and therefore the martensitic structure cannot

Obtained sufficiently in the quenching process, which results in a decrease in the resistance of the tube from the lal. Moreover, the hardness obtained by the following prepared tempering treatment is insufficient. It is preferable according to the manufacturing method of the oil casing tube from the present disclosure and in step (1B) that

0 The seamless pipe is heated to a temperature of 803 to 1000°C and then cooled to a temperature of 100 m or less at a cooling rate of 10-100 m/hr. In the previous embodiment, the reason for the heating, which takes place at a temperature of 1000 °C or less, is that the austenite structure will grow when heated at a temperature above 1000 °C in the quenching process, so that the impact hardness increases.

5 Detailed Description: Oil Casing Tube (LAL) martensini stainless steel resistant to hydrogen sulfide stress corrosion cracking and Oil Casing Tube and its fabrication as per the present Disclosure will be explained in detail with reference to specific examples. However, this explanation is not intended to define the scope of the technical solution from the present disclosure.

0 Examples from 1-16 and comparative examples from 1-8 Oil casing pipes were manufactured in the above-mentioned examples and the comparative examples using the following steps: (1) Manufacturing pipe blanks for Molten tubes steels combinations of examples and comparative examples illustrated in the list in Table 1

5 (2) Rolling tubes sealed in order to reach seamless steel tubes. A small rolling mill was used to punch round billets for manufacturing

The steel tube which is then cooled in air thus providing a seamless steel tube having a size of 73.02 mm (outside diameter) % 7.01 mm (bar thickness). (3) Heating the tubes of seamless steel according to the following steps: (13) Quenching: The seamless steel tubes are heated at a temperature from AC3 to 1000 m, and then cooling is done at 100 m or less at a cooling rate of 10-100 m/h in order to form a martensitic structure.(3b) first quenching: seamless steel tubes are heated at 71 for first quenching where 71 is 600-670°C; the stopping time is 40 minutes; (3c) metal quenching Second: The second watering was performed at a Sha of 72, which is 40-2-71 0°C and there is a cut-off time of 40 minutes. Oxygen, phosphorus, and sulfur (kr | dam a mad kro | nick | align | nida a vanad [5] | ak | fawa kibber vana walada|jund/am|l|m| saw a day | since a record a yt | duo naqua| g jd m | yen | wrm: n n 3 c n n J yt + yen ( [o0. Jo. [ox [o. [23 [4 13]] 0.[0.]0. |wy 10 .4.10 2210|18 4 02|45 0110004 01 0 g |1 6 22|8 digit

Hee

4.10 10 10 0 040 [184 [13] 0. [0.]0 [wy 8 100|02 000343] [07 0 |2 [320110 n| 12 2 2 3 12 5 No. 2 range [0.10] 10.12 5 .05 [0]. 0] 10.10.7.10 0 8101 5 M 100 (01000296) 5 11 |28 6 [19 No. 3 5.10.10.] 0. [0.0210 1224 1110 0.0 wy 1 loo |o1]00]|03]63 |03 2 16 [85]1 0 the |2 2 25 4 n.4 2.10.10.10. [0.[02] | 1 331 |o | 6 6 Da No. 7 410 10.10 [0 10310 [186 |11.110 | wu 2 100011000291 8 7 11 110 M4 23 2 No.

Sha 0. [0] .0 14] 214] 0510 0 10 10 410 0 321 0 and Mada Dama 0m 03 00 1 [3d 2 6 19 5 No. 9 Sha 0.0 .13. [0] 12115 0210 .0] .0[.10.0 0 8711] 14 5 00 03 | 00 [01 | 00 God | 1 9 24 | sa 1 no

Sha 0.0 11310 194 [0210 0 0 10 2.10 0 1 2 wa 17 4 8 23 1 m 00 01 00 2 no | Da 1 28 [6| 4 No. 11 winter 0.[0] 12.11 25[6] 0210 0 10 10 2.10 10 7 5 07| 000110010216 3 gl 4|Y 4 6 12 7 digit 12 [wy 0.]0[ .10 .11| 195[ .1020 .10.10 .10 .0 |s5]1 0 418 29| 0433 | 00 [01 | 00 519 21 1 digit 13 1112.10 [0.]0 |g 1.614 0410 0 0 .10 10 4 0 6211| 16 2 + FD 00000003 3 God | Da g 2212[ 9 No. 14 AH .0.0 13.10 12115 .0510 .0[ .0[ .10 .5.10 |s9]1 |o 15 2 07| 100|01|00]|04|37 and Alk| da and 1 3 18 1 digit

Genm uh ed dd ada nd dd dd ada

7.10. 10.10 [0. 5 18 12.10. [0.10 [wy 8 100] [01] [000346 8 [7211 0]

8 [3|18 3(11]9).

number

16

1100010 0 0012 5.13.10 10.10 |g 5010001 00 wa 7 03 4 AH [7711 0

god | 1| 5 4 3 4| 73

2all

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1

2.10. 10. [0. [0. 102/0 [3515 112.10. 0.0 [wy 1 |0001 00038 9 7 4a 6211 0

the | 4 1 4 3 2 a 2

2all

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2

6.10 001010 02/0 [243 [14 0] 0.]0 [wy 3 00010010222 1 715 371 0

20219 5 DDA 7 A 9

2all

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3

Ha.0.0.13.[0]6] 1011012 0010.0] 1.210 0 01 84a 13 5 05| Da 04 03 00102 9

4 [2 51019

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4

Table No. 1 above shows lists of the mass ratios of many chemical elements of steel materials for oil casing pipes in examples and comparative examples, as well as in the form of values of

— 6 1 — Vanadium: (carbon (Cag yi) » when Jia vanadium; kreon and nitrogen are the mass ratios of the corresponding elements. The values placed under the line in Table 1 show that these values exceed the range of ranges indicated by the detection. Table 2 Process parameters specified in the manufacturing method of the examples and comparative examples as well as the results of performance tests of the examples and comparative examples Table 2 rtgt quenching rate 1 124 hardness impact resistance aay test ( ) for hardness _ fracture rate yy 00606178 rtgt - 20- To eat the product of Cooling ‘to prevent’. m (sperm) 0 ‘shake’ (degree) to eat id (40 ge 20 [e.g. HRC) 5 Wl) °C / minute) (ARC) —sidy aifal as for particular tensile| yield 50 506081 by stress (TS) (YS) of a sulfide Pascal (Jul constant for example 950 12 665 625 683 82606 122 26.5 0.097 Nm : 1 for example 950 20 5 625 865 [131 25.9 0.088 mm: 2 ys] 950 30 665 625 721 880 1153 26.1 0.061 mm; 3 for Article 30 665 625 675 863 [125 25.8 mm: 0.106

Article 50 665 625 657 868 118 26.6 0.079 Qm: 5

0.103 26.2 119 880 670 620 50 Jal 6 Qom:

Ex: 950 30 60 685 865 129 25.9 0.103 QM: 7

0.065 26.0 124 861 665 0 30 950 js 8 Qom:

Ex: 950 40 60 691 [871 11606 25.7 0.102 QM: 9

0.064 26.3 132 800 714 | 620 Jd x

0.102] 26.2 128 820 670 615] 655 50 for x article

11

0.068 25.9 130 863] 698 615] 655 50 for x article

12

0.087 25.8 127 887 682 615] 655 30 950] for example x

13

0.084 25.6 130, 805 713 615] 655 30 950] sa x

14

0.080] 25.9 136] 801] 686] 615 655 20 950] for example x

8-1 — A EN EE A A I I I et For Article 30 650 [610] 681 8760 128 26.9 0.085 Qom: 16 For Article 40 650 610 2 72 28.06 0.073 For Comparator: Article Qom: 1 For Article 50 650 671610 865 620 18.39 Lm: 1 The article Qom: 2 for example950 650 610 625 778 83 .29 0.176 for the comparator: the article Qom: 3 psy 950 50 0 610 719 880 3 0.170 for the comparison: the article Qom: 4 for the example 950 40 665 694 830 115 for the comparison: the article Qom: 0.062 for the comparison Qom: 5 for an article 30 665 695 8635 120 27.2 0.084" for a comparison:

Article A. Mithqal 20 665 5 885 129 27.5 094. Wadi Muqarani: Article Qom: 7 Mithqal 20 665 678 860 125 27.8 0.064 Comparison: Article Qom: 8 In Table 2 above, the comparative examples from 1-4 have the following steel composition Corresponding types of steel from comparative Examples 4-1 in Table 1 and Comparative Examples 8-5 which have mass percentages of chemical elements corresponding to Examples 1-4 in Table 1. In order to verify the effect of the process on the effects of the models of the present disclosure of step (3c) is not performed in the manufacturing method of Comparative Examples 8-5.In Table 2 above performance test results were obtained by performing the following tests: (a) resistance test: lial tube treated) Which does not rust in an arc sample of type API and was tested according to APL standards The averages were obtained to give (0-output strength) and (tensile strength).(2) Impact hardness test: Distinguished Hardness at impact by the impact absorbing energy of the notch Charpy V. An impact sample was cut with a notch in the shape of - 7? ? Ally notch impact sample having ana 55*10*5 (mm) stainless steel tube 0 The test was carried out at a temperature of -20°C. Average obtained from 5 was tested according to AGB/T 229 8013/1229 standard and converted to impact hardness at -20°C with full size of 10*10*55 (mm) according to ABI standard

API5CT

(3) Stiffness test: the cross-section of seamless steel pipe has been subjected to a test

Rigidity using a Rockwell durometer at -20 m and this is done

Jaa hardness points in its intermediate form to obtain a hardness of -20 m 5 (4) Corrosion test: A seamless steel tube was immersed in liquid in an autoclave

At 150 m where the partial pressure of carbon dioxide was 6 MPa and the ion concentration was

Chloride is 100,000 mg/L and the liquid flow rate is 1 ml/sec and the test time is

is 240 hours. Sample weights were compared before and after the test and the corrosion rate was obtained

regular accounts.

0 (5) SSC test (Corrosion Cracking of Sulfide Stress for Constant Load): A stress ring tester was used to perform the test Stress wear fracture ain Sl for static load according to Method A in GB/T 61/1 2006-4157.The stress test was performed with 0.01 MPa hydrogen sulfide gas (the residual is carbon dioxide) and the

5 Saturation at 725 NaCl sodium chloride solution (pH 4.0) with 785 specific resistance obtained at its lower limit where the test temperature is 24 °C and the test cycle is 720 h. Done Samples tested for each example. Samples were tested at the end of the test cycle. The results of the test are shown in Table 2 where “MV” indicates no frizz and “©” indicates fructification.

0 and as shown in Table 2 above; The oil casing tubing in Examples 1-6 has a strength of 655 MPa or greater which satisfies the requirements of 95 kpi. The impact hardness at -20°C is 100 J or higher and the hardness is 27 HRC or less. All of these materials showed uniform and superior corrosion resistance at 0°C in a medium containing carbon dioxide and a high concentration of chloride ion. did not

5 No sulfide stress corrosion fracturing is observed in the sulfide stress corrosion fracturing test for static load under conditions of 24 m. Those characteristics are superior to those of the private

with casing tubes in comparative examples 1-8. The oil casing pipes of the present disclosure have important advantages, such as high hardness at high corrosion resistance. These tubes can be used in crude oil wells or in natural gas containing a strong corrosive medium where hydrogen sulfide is at a pressure (Sia) of about 0.01 MPa and crion dioxide, chloride ion and the like are co-existing at high concentrations. Moreover, the oil casing pipe can meet relevant requirements on corrosion resistance and mechanical properties

in this milieu. It should be noted that the above list is only examples of the invention. Clearly, the invention does not comply with the previous examples. Instead; Many similar variable 0 images can exist. All variants derived or directly accessed from the disclosure of the invention by those skilled in the art should be included in the scope of the invention.

Claims (1)

protection elements 1. A material from (Glial) for the oil casing pipe made of martensitic stainless steel, and this material is resistant to fracturing and corrosion by hydrogen sulfide stress, and it contains chemical elements Next 7 by mass: 0 < (C) carbon > 70.05 (Si) silicon : 0.2-0.1 manganese 7.0-4.0 : (Ni) nickel 14.0-11.0; Tickle : (Cr) chromium ¢/1.0-0.20 : (Mn) vanadium ¢£0.10-0.001 : (N) nitrogen ¢/£2.5-1.5 : (Mo) Molybdenum Molybdenum With a balance amount of 70.04-0.01: (AD) aluminum and 70.6-0.03: (V) Vanadium and waste that cannot be chelated; (Fe) iron was sabe 0 where chemical elements also meet vanadium (Creon, carbon + nitrogen, 2:1 to 8:1, where vanadium, creon, carbon, and nitrogen represent the mass percentiles of the corresponding elements, respectively; Casing pipe of bill martensitic stainless steel and toughness impact energy at 5 degrees low temperature above 100 joules at -20 degrees Adie sal 2 casing tube for oil casing pipe It is made of martensitic stainless steel according to protection element 1, where manganese is 0.02 -70.5 sale 3. The ribs for the oil casing pipe are made of martensitic stainless steel according to protection element 1, where 70.003 is carbon > 70.05. 4. A casing pipe, as it was manufactured from the pulp material for an oil casing pipe 5 of martensitic stainless steel according to any of the elements 3-1 protection 5. Oil casing pipe according to Clause 4, as the oil hall casing pipe has a yield resistance in the yield higher than 655 MPa and the ability to resist Jbl fracturing caused by algal Hydrogen sulfide A medium containing hydrogen sulfide that has a partial pressure (Aya) of up to 0.01 MPa. 6. Manufacturing method of oil casing pipe according to any of the protection elements 0-4 5 which includes the following steps in order: (1) manufacturing of an oil casing pipe blank dala (2) an airtight pipe pipe blank is accessed for a seamless lal pipe ¢ seamless steel pipe 6 heating the pipe from the seamless steel pipe according to the following steps: 5 ( 3) quenching the image of the 'martensitic structure' 3) <(First metal tempering: heating seamless steel pipe to T1 for first tempering which is 11 from 600-670 degrees Agia (£3) metal quenching ¢Aull tempering A second tempering of the metal is performed at a temperature of 0 by 12 Cua which is 12-11-40°C. 7. The method of manufacturing the oil casing pipe according to Clause 6, where in step (13) the seamless casing pipe is heated to AC3 or higher in order to be quenched and then cooled to a degree shad is 100 degrees Celsius or less. 8. The method of manufacturing the oil casing pipe according to Clause 7 Cua in step 0 2 4 0 1000 to AC3 is heated from the seamless steel pipe temperature (3) degrees Celsius or less at a cooling rate of 100 shall degrees Celsius and then cooling to a degree Degress/min. 1000 -0 Sued Authority for Intellectual Property RE .¥ + \ A 0 § 8 Ss o + < M SNE A J > E K J TE I UN BE Ca a a a ww > Ld Ed H Ed - 2 Ld, provided that the annual financial consideration is paid for the patent and that it is not null and void for violating any of the provisions of the patent system, layout designs of integrated circuits, plant varieties and industrial designs, or its implementing regulations. Ad Issued by + bb 0.b The Saudi Authority for Intellectual Property > > > This is PO Box 1011 .| for ria 1*1 v= ; Kingdom | Arabic | For Saudi Arabia, SAIP@SAIP.GOV.SA