WO2021078255A1 - Anti-collapse petroleum casing pipe and manufacturing method therefor - Google Patents

Abstract

Disclosed is an anti-collapse petroleum casing pipe, comprising, in mass percent, the following chemical elements: 0.08-0.15% of C, 0.1-0.4% of Si, 0.1-0.3% of Mn, 1-1.5% of Cr, 1-1.5% of Mo, 0.04-0.08% of Nb, 0.15-0.25% of V, 0.02-0.05% of Ti, 0.0015-0.005% of B, 0.01-0.05% of Al, and 0.002-0.004% of Ca, with the balance being Fe and other inevitable impurities. In addition, also disclosed is a manufacturing method for the anti-collapse petroleum casing pipe, comprising the steps of: (1) smelting and continuous casting; (2) perforating; (3) rolling; (4) controlled cooling; (5) quenching + tempering; (6) hot sizing and hot straightening.

Description

Anti-collapse oil casing pipe and manufacturing method thereof Technical field

The invention relates to a steel pipe and a manufacturing method thereof, in particular to a petroleum casing pipe and a manufacturing method thereof.

Background technique

Deep wells and ultra-deep wells are one of the more and more wells developed in the field of petroleum exploration and development in recent years. In order to ensure the safety of high-temperature and high-pressure exploitation and development, high requirements are put forward on the strength of the pipe string materials. While ultra-deep pipe strings are used in oil and gas production, they must also withstand physical loads such as high temperature and high pressure. For example, the casing in the middle and deep parts of the Tarim Basin needs to adopt high collapse resistance. Therefore, the requirements for the strength of the casing are significantly increased. However, while increasing the strength, the hardness of the material will increase correspondingly, the toughness of the material, especially the fracture toughness will gradually decrease, and the sensitivity of the material to surface defects will further increase, making the casing happen in the high pressure environment downhole The crack expands, leading to failure. The fracture toughness K _IC of metal materials is an important material mechanical performance index in fracture mechanics. For high-strength pipes serving in complex environmental conditions, fracture toughness is particularly important. Therefore, in order to ensure the safety of production and use, casings used in deep wells and ultra-deep wells have high requirements for strength and fracture toughness.

For example: the publication number is CN101586450, the publication date is November 25, 2009, and the Chinese patent document titled "Petroleum casing with high strength and high toughness and its manufacturing method" discloses a petroleum casing with high strength and high toughness. tube. In the technical solution disclosed in this patent document, the chemical element composition is: C: 0.22 to 0.4%, Si: 0.17 to 0.35%, Mn: 0.45 to 0.60%, Cr: 0.95 to 1.10%, Mo: 0.70 to 0.80 %, Al: 0.015～0.040%, Ni<0.20%, Cu<0.20%, V: 0.070～0.100%, Ca>0.0015%, P<0.010%, S<0.003%, the balance is iron. It should be pointed out that in the technical solution disclosed in the patent document, although the strength of the steel grade reaches 1100 MPa, it does not give a specific index for the fracture toughness.

Another example: in the technical solution disclosed in the Chinese patent document with the publication number CN106834970A, the publication date being June 13, 2017, and the title "a low-alloy ultra-high-strength steel and a method for preparing seamless steel pipes", the steel This kind of strength reaches 140ksi, but its impact toughness and fracture toughness are very low, which cannot meet the toughness requirements of the casing in the deep well environment.

Another example: the publication number is CN101250671A, the publication date is August 27, 2008, and the Chinese patent document entitled "Petroleum casing with high strength and high toughness and its manufacturing method" discloses a kind of high strength and high toughness. The steel grade of oil casing. In the technical solution disclosed in this patent document, the transverse impact toughness of the steel grade is only 80J, and the impact toughness is also low.

Summary of the invention

One of the objectives of the present invention is to provide a collapse-resistant oil casing, which has ultra-high strength, ultra-high collapse strength and high fracture toughness, and can meet the requirements of oil well pipes in deep well and ultra-deep well oil and gas fields. The strength, collapse resistance and fracture toughness requirements.

In order to achieve the above-mentioned purpose, the anti-collapse oil casing provided by the present invention has the following chemical element mass percentage:

C: 0.08-0.15%, Si: 0.1-0.4%, Mn: 0.1-0.3%, Cr: 1-1.5%, Mo: 1-1.5%, Nb: 0.04-0.08%, V: 0.15-0.25%, Ti : 0.02-0.05%, B: 0.0015-0.005%, Al: 0.01-0.05%, Ca: 0.002-0.004%, the balance is Fe and other unavoidable impurities.

The anti-collapse oil casing of the present invention adopts a low-carbon composition design, which reduces the _{formation of large-sized Cr 23} C ₆ and Mo ₂ C carbides, so that Cr and Mo elements exist in a solid solution form. The solid solution strengthening effect of Cr and Mo and the precipitation strengthening effect of V, Nb, and Ti achieve good strength and fracture toughness.

In addition, the anti-collapse oil casing of the present invention adopts a low-manganese composition design to improve composition segregation, and prevent the occurrence of alloy-enriched composition segregation zones on the inner wall of the tube causing uneven local organization and carbide distribution. In order to improve the fracture toughness index of the material; at the same time, in order to improve the low carbon component system hardenability, the problem of low martensite ratio after quenching, B and Ti are added to improve the hardenability and the uniformity of the structure in the material to improve fracture Toughness and strength.

The design principles of each chemical element are as follows:

C: In the anti-collapse oil casing pipe of the present invention, C is a carbide forming element, which can increase the strength of steel. When the mass percentage of C is less than 0.08%, the hardenability of the steel will be reduced, thereby reducing the strength of the steel. However, when the mass percentage of C is higher than 0.15%, the segregation of the steel will be significantly worsened, which will cause the steel The toughness is reduced. In order to meet the requirements of high strength and high toughness of the petroleum casing, the anti-collapse petroleum casing of the present invention controls the mass percentage of C to 0.08-0.15%. In some preferred embodiments, the mass percentage of C can be further controlled within 0.1-0.15%.

Si: In the anti-collapse oil casing pipe of the present invention, Si is solid-dissolved in ferrite, which can increase the yield strength of steel, but the amount of Si added should not be too high, and Si with too high mass percentage will deteriorate the steel However, Si with a mass percentage of less than 0.1% will make the oil casing easy to oxidize. Based on this, the anti-collapse oil casing pipe of the present invention controls the mass percentage of Si within 0.10-0.40%.

Mn: In the anti-collapse oil casing pipe of the present invention, Mn is an austenite-forming element, which can improve the hardenability of steel. When the mass percentage of Mn is less than 0.1%, the hardenability of the steel will be significantly reduced, thereby reducing the proportion of martensite in the steel after quenching, thereby reducing the strength of the steel; when the mass percentage of Mn is greater than 0.3%, the hardenability of the steel The structure segregation will increase significantly, which will reduce the fracture toughness of steel. Based on this, the anti-collapse oil casing pipe of the present invention controls the mass percentage of Mn within 0.1-0.3%.

Cr: In the collapse-resistant petroleum casing pipe of the present invention, Cr is an element that significantly improves hardenability and a strong precipitate-forming element. During tempering precipitation, the precipitates can increase the strength of the steel, but if the mass percentage of Cr is higher than 1.5%, coarse M ₂₃ C ₆ precipitates are likely to precipitate on the grain boundaries, reducing the toughness. When the mass percentage of Cr is less than 1%, the hardenability will be insufficient and the quenching effect cannot be guaranteed. Based on this, the mass percentage of Cr in the anti-collapse oil casing pipe of the present invention is controlled to be 1-1.5%. In some preferred embodiments, the mass percentage of Cr can be further controlled within 1-1.4%.

Mo: In the anti-collapse oil casing pipe of the present invention, Mo improves the strength and tempering stability of steel through carbide and solid solution strengthening forms. Since the mass percentage of carbon in this case is low, when the mass percentage of Mo is more than 1.5%, it is difficult for Mo to form more carbide precipitation phases with C, and the strength does not change significantly; and once the mass percentage of Mo is lower than At 1%, the strength of the anti-collapse oil casing pipe of the present invention cannot reach the requirement of 140 ksi. Therefore, the mass percentage of Mo in the anti-collapse oil casing pipe of the present invention is controlled at 1 to 1.5%. In some preferred embodiments, the mass percentage of Mo can be further controlled within 1-1.4%.

Nb: In the anti-collapse oil casing pipe of the present invention, Nb is a fine-grained and precipitation-strengthening element in steel, which can compensate for the decrease in strength caused by the decrease in carbon content. When the mass percentage of Nb is less than 0.04%, its addition effect is not obvious. When the mass percentage of Nb is greater than 0.08%, it is easy to form coarse Nb(CN), thereby reducing the toughness of the steel. Based on this, the anti-collapse oil casing pipe of the present invention controls the mass percentage of Nb at 0.04-0.08%. In some preferred embodiments, the mass percentage of Nb can be further controlled within 0.06-0.08%.

V: In the anti-collapse oil casing of the present invention, V is a typical precipitation strengthening element, which can compensate for the decrease in strength caused by carbon reduction. When the mass percentage of V is less than 0.15%, it is difficult to make the present invention The strength of the said anti-collapse oil casing reaches 140ksi. However, if the mass percentage of V is higher than 0.25%, coarse V(CN) is likely to be formed, thereby reducing toughness. Based on this, the anti-collapse oil casing pipe of the present invention controls the mass percentage of V at 0.15-0.25%. In some preferred embodiments, the mass percentage of V can be further controlled within 0.2-0.25%.

Ti: In the anti-collapse oil casing pipe of the present invention, Ti is a strong carbonitride forming element, which can significantly refine the austenite grains in the steel, and can compensate for the strength caused by the decrease in carbon content decline. If the mass percentage of Ti>0.05%, it is easy to form coarse TiN, which will reduce the toughness of the material. If the mass percentage of Ti is less than 0.02%, Ti cannot fully react with N to form TiN, and B in the steel will react with N to form a brittle phase of BN, thereby reducing the toughness of the material. Based on this, the mass percentage of Ti in the anti-collapse oil casing pipe of the present invention is controlled at 0.02-0.05%. In some preferred embodiments, the mass percentage of Ti can be further controlled within 0.03-0.05%.

B: In the anti-collapse oil casing pipe of the present invention, B is also an element that can significantly improve the hardenability of steel. In this case, since the mass percentage of C is low, the addition of B element can solve the problem of poor hardenability caused by the decrease in the mass percentage of C. However, when the mass percentage of B is less than 0.0015%, the effect of improving the hardenability of the steel is not significant; when the mass percentage of B is higher than 0.005%, BN brittle phases are easily formed, thereby reducing the toughness of the steel. Based on this, the mass percentage of B in the anti-collapse oil casing pipe of the present invention is controlled at 0.0015 to 0.005%. In some preferred embodiments, the mass percentage of B can be further controlled within 0.0015 to 0.004%.

Al: In the anti-collapse oil casing pipe of the present invention, Al is a good deoxidation and nitrogen fixation element and can refine crystal grains. Therefore, the mass percentage of Al in the anti-collapse oil casing pipe of the present invention is controlled at 0.01-0.05%.

Ca: In the anti-collapse oil casing of the present invention, Ca can purify molten steel, promote spheroidization of MnS, and improve fracture toughness, but when the content is too high, it is easy to form coarse non-metallic inclusions. Therefore, the present invention limits the mass percentage of Ca element in the thick-walled, high-strength and high-toughness petroleum casing to 0.002-0.004%.

Further, in the anti-collapse oil casing pipe of the present invention, the mass percentage of each chemical element also satisfies at least one of the following items:

C: 0.1-0.15%;

Cr: 1-1.4%;

Mo: 1-1.4%;

Nb: 0.06-0.08%;

V: 0.2-0.25%;

Ti: 0.03-0.05%;

B: 0.0015 to 0.004%.

Further, in the anti-collapse oil casing pipe of the present invention, among the other unavoidable impurities: S≤0.003%.

Further, in the collapse-resistant oil casing pipe of the present invention, the mass percentages of Ca and S elements satisfy Ca/S≥2.

Further, in the collapse-resistant oil casing pipe of the present invention, among the other unavoidable impurities: N≤0.008%, and/or P≤0.015%.

Further, in the anti-collapse oil casing pipe of the present invention, the microstructure is tempered sorbite. Tempered sorbite is the formation of martensite after quenching the casing, which is then tempered to finally form tempered sorbite.

Furthermore, the collapse-resistant petroleum casing pipe of the present invention may also contain at least one of the following chemical elements: 0<Ni≤0.2%, 0<Cu≤0.2%, 0<Re≤0.1%; Further improve the performance of oil casing.

Further, in the collapse-resistant petroleum casing pipe of the present invention, its performance indicators meet at least one or all of the following items: the yield strength is 965-1173 MPa, the tensile strength is ≥ 1034 MPa, and the elongation rate is ≥ 20%. , Fracture toughness K _IC value ≥150MPa·m ^1/2 , 0°C transverse Charpy impact energy ≥120J, ductile brittle transition temperature ≤-60°C, collapse resistance performance exceeds API standard by more than 25%. Specifically, the yield strength is 965 to 1173 MPa, the tensile strength is 1034 to 1241 MPa, the elongation is 20% to 30%, the fracture toughness K _IC value is 150 to 260 MPa·m ^1/2 , and the transverse Charpy impact energy at 0°C is 120～150J, the ductile-brittle transition temperature is -60～-80℃, the collapse resistance performance exceeds the API standard by 25%～65%.

Correspondingly, another object of the present invention is to provide a method for manufacturing the above-mentioned collapse-resistant petroleum casing, through which a petroleum casing with ultra-high strength, ultra-high collapse strength and high fracture toughness can be obtained. It can meet the requirements of strength, collapse resistance and fracture toughness for oil well pipes in deep well and ultra-deep well oil and gas fields.

In order to achieve the above-mentioned object, the present invention proposes the above-mentioned anti-collapsed petroleum casing manufacturing method, which includes the steps:

(1) Smelting and continuous casting;

(2) Perforation;

(3) Rolling: control the final rolling temperature to 900～950℃, and perform tension reduction after finishing rolling, the temperature is 850～900℃;

(4) Controlled cooling: on-line water cooling, cooling rate of 15-25℃/s, cooling to 600-650℃, then air cooling to room temperature;

(5) Quenching + tempering: the quenching temperature is 900～950℃, the holding time is 30～60min; the tempering temperature is 650～700℃, and the holding time is 50～80min;

(6) Thermal sizing and thermal straightening.

In the manufacturing method of the present invention, considering that the steel type in this case is a low-carbon steel type, the high temperature deformation resistance is small, therefore, in step (3), the final rolling temperature is controlled at 900-950°C, and the tension reduction temperature is At 850-900℃, it is helpful to refine the grain to improve the fracture toughness.

In addition, step (4) is set after step (3), by cooling the outer surface of the sleeve, and controlling the cooling rate to be 15-25°C/s, cooling to 600-650°C, so as to improve the strength and fracture of the material toughness. The inventor of the present case found through a lot of research that in the prior art, because the controlled cooling process is not used in the rolling process, the casing is in a high temperature state during the rolling process. Therefore, the microstructure after the high temperature is cooled to the low temperature in the rolling process It is a mixed structure of one or more of ferrite + pearlite, bainite, and Widmanstatten structure, and the austenite grains are coarser, which makes the strength and impact toughness of the material lower. Moreover, the grain size is hereditary, and the material has coarse grains after the subsequent quenching and tempering heat treatment process, resulting in low toughness and plasticity. The technical solution of the present invention adopts a controlled cooling process after rolling, which increases the degree of undercooling of the material and inhibits the formation of coarse ferrite+pearlite and upper bainite structure and Widmanstatten structure. In addition, cooling to 600-650°C at a cooling rate of 15-25°C/s transforms the material structure into a finer bainite structure, refines the grains, improves the uniformity of the material composition, and significantly improves The strength and toughness of the material are also conducive to improving the collapse resistance.

Further, in the manufacturing method of the present invention, in step (2), the round billet is soaked at 1260 to 1290°C, and then perforated after soaking, the perforation temperature is 1180 to 1240°C, so as to ensure that the casing has a good quality High temperature plasticity to reduce the incidence of defects.

Further, in the manufacturing method of the present invention, in step (1), the continuous casting drawing speed is controlled to be 1.6-2.0 m/min to improve the segregation of components in the tube blank.

Further, in the manufacturing method of the present invention, in step (6), the heat sizing temperature is 500-550° C. to improve the straightening effect and increase the straightness of the casing.

Compared with the prior art, the collapse-resistant oil casing pipe and the manufacturing method thereof of the present invention have the following advantages and beneficial effects:

The collapse-resistant petroleum casing of the present invention has ultra-high strength and high fracture toughness, and its performance indicators meet at least one or all of the following items: the yield strength is 965-1173MPa, the tensile strength is ≥1034MPa, Elongation ≥20%, fracture toughness K _IC value ≥150MPa·m ^1/2 , 0°C transverse Charpy impact energy ≥120J, ductile brittle transition temperature ≤-60°C, collapse resistance performance exceeds API standards by more than 25%. Specifically, the yield strength is 965 to 1173 MPa, the tensile strength is 1034 to 1241 MPa, the elongation is 20% to 30%, the fracture toughness K _IC value is 150 to 260 MPa·m ^1/2 , and the transverse Charpy impact energy at 0°C is 120～150J, the ductile-brittle transition temperature is -60～-80℃, the collapse resistance performance exceeds the API standard by 25%～65%.

In addition, in addition to the above-mentioned advantages and beneficial effects, the manufacturing method of the present invention also has the advantages of simple operation, easy realization of large-scale production and manufacturing, and good economic benefits.

Detailed ways

The following will further explain and describe the collapse-resistant oil casing and the manufacturing method of the present invention in conjunction with specific embodiments, but the explanation and description do not improperly limit the technical solution of the present invention.

Examples 1-5 and Comparative Examples 1-5

The anti-collapse oil casing pipes of Examples 1-5 and the comparative casing pipes of Comparative Examples 1-5 were prepared by the following steps:

(1) Smelting and continuous casting are carried out in accordance with the ingredients listed in Table 1, and the continuous casting speed is controlled to be 1.6~2.0m/min.

(2) Piercing: The round billet obtained in step (1) is soaked at 1260-1290°C, and then pierced after soaking, and the piercing temperature is 1180-1240°C.

(3) Rolling: control the final rolling temperature to 900-950°C, and perform tension reduction after the final rolling, and the temperature is 850-900°C.

(4) Controlled cooling: On-line water cooling is performed at a cooling rate of 15-25°C/s, cooling to 600-650°C, and then air cooling to room temperature.

(5) Quenching + tempering: the quenching temperature is 900～950℃, the holding time is 30～60min; the tempering temperature is 650～700℃, and the holding time is 50～80min.

(6) Thermal sizing and thermal straightening: The temperature of thermal sizing is 500～550℃.

Table 1 lists the mass percentage ratios of the chemical elements of the anti-collapse oil casings of Examples 1-5 and the comparative casings of Comparative Examples 1-4.

Table 1. (wt%, the balance is Fe and other unavoidable impurities except P, S and N)

Serial number	C	Si	Mn	Cr	Mo	Nb	Ti	B	Al	N	V	Ca	S	Ca/S
Example 1	0.08	0.2	0.1	1	1	0.04	0.02	0.0015	0.01	0.004	0.15	0.002	0.0007	2.9
Example 2	0.11	0.1	0.2	1.1	1.1	0.05	0.025	0.002	0.04	0.005	0.18	0.003	0.001	3.0
Example 3	0.13	0.3	0.3	1.2	1.2	0.06	0.04	0.003	0.05	0.006	0.20	0.004	0.0011	3.6
Example 4	0.15	0.4	0.2	1.4	1.4	0.07	0.04	0.004	0.03	0.007	0.22	0.0025	0.0008	3.1
Example 5	0.13	0.25	0.1	1.5	1.5	0.08	0.05	0.005	0.02	0.008	0.25	0.0035	0.0009	3.9
Comparative example 1	0.25	0.26	0.1	0.5	0.6	0.04	0.02	0.0015	0.01	0.004	0.15	0.002	0.0007	2.9
Comparative example 2	0.15	0.33	0.2	1.1	1.1	0.05	-	-	0.04	0.005	0.18	0.003	0.001	3.0
Comparative example 3	0.13	0.3	1	1.4	1.4	0.02	0.04	0.004	0.03	0.007	0.10	0.0025	0.0008	3.1
Comparative example 4	0.13	0.3	0.1	1.5	1.5	0.08	0.05	0.005	0.02	0.008	0.25	0.0005	0.0010	0.5

Table 2 lists the specific process parameters of the anti-collapse oil casing pipes of Examples 1-5 and the comparative casing pipes of Comparative Examples 1-4.

Table 2.

Table 3 lists the test results obtained according to the test standards of ASTM A370, ASTM E23, and ISO/TR10400 for the anti-collapse oil casing pipes of Examples 1-5 and the comparative casing pipes of Comparative Examples 1-4.

table 3.

It can be seen from Table 3 that the performance of each embodiment of this case satisfies all of the following items: yield strength is 1030-1150MPa, tensile strength ≥1090MPa, elongation ≥22%, fracture toughness K _IC value ≥205MPa·m ^1/2 , 0°C transverse Charpy impact energy ≥126J, ductile-brittle transition temperature ≤-60°C, and collapse resistance performance exceeds the API standard by more than 40%, which shows that the examples of this case are very suitable for making deep and ultra-deep wells. tube.

On the other hand, in the comparative example, the C, Cr and Mo in the comparative example 1 are beyond the limits of this case, the B and Ti are not added in the comparative example 2, and the Mn, V, and Nb in the comparative example 3 exceed the limits in this case Range, so that at least one of the mechanical properties of the comparative casings of Comparative Examples 1-3 failed to meet the standards of high strength, high collapse resistance and high fracture toughness petroleum casing, and the overall performance was not as good as the collapse resistance of each embodiment of this case Destroy the oil casing. In Comparative Example 4, Ca/S does not meet the requirements of Ca/S and the mass percentage of S elements meets Ca/S≥2. Therefore, the performance parameters of Comparative Example 4 are worse than those of Comparative Examples 1-3, but its overall performance is not as good as The collapse-resistant oil casing pipe of each embodiment of this case.

In summary, the collapse-resistant petroleum casing of the present invention has ultra-high strength and high fracture toughness, and its performance indicators meet all of the following items: the yield strength is 965-1173MPa, the tensile strength is ≥1034MPa, Elongation ≥20%, fracture toughness K _IC value ≥150MPa·m ^1/2 , 0°C transverse Charpy impact energy ≥120J, ductile brittle transition temperature ≤-60°C, collapse resistance performance exceeds API standards by more than 25%.

In addition, in addition to the above-mentioned advantages and beneficial effects, the manufacturing method of the present invention also has the advantages of simple operation, easy realization of large-scale production and manufacturing, and good economic benefits.

It should be noted that the prior art part of the protection scope of the present invention is not limited to the embodiments given in this application document, and all prior art that does not contradict the solution of the present invention includes but is not limited to the previous Patent documents, prior publications, prior publications, etc., can all be included in the protection scope of the present invention.

In addition, the combination of various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features described in this case can be freely combined or combined in any way, unless Contradictions arise between each other.

It should also be noted that the embodiments listed above are only specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and the subsequent similar changes or modifications are those skilled in the art can directly derive or easily associate from the disclosure of the present invention, and they should all fall within the protection scope of the present invention. .

Claims (12)

1. An anti-collapse oil casing pipe, characterized in that its chemical element mass percentage is:

   C: 0.08-0.15%, Si: 0.1-0.4%, Mn: 0.1-0.3%, Cr: 1-1.5%, Mo: 1-1.5%, Nb: 0.04-0.08%, V: 0.15-0.25%, Ti : 0.02-0.05%, B: 0.0015-0.005%, Al: 0.01-0.05%, Ca: 0.002-0.004%, the balance is Fe and other unavoidable impurities.
2. The collapse-resistant oil casing pipe of claim 1, wherein the mass percentage of each chemical element also satisfies at least one of the following items:

   C: 0.1-0.15%;

   Cr: 1-1.4%;

   Mo: 1-1.4%;

   Nb: 0.06-0.08%;

   V: 0.2-0.25%;

   Ti: 0.03-0.05%;

   B: 0.0015 to 0.004%.
3. The collapse-resistant oil casing pipe according to claim 1, characterized in that, among the other unavoidable impurities: S≤0.003%.
4. The collapse-resistant oil casing pipe of claim 3, wherein the mass percentage content of Ca and S elements satisfies Ca/S≥2.
5. The collapse-resistant petroleum casing pipe according to claim 1, characterized in that, among the other unavoidable impurities: N≤0.008%, and/or P≤0.015%.
6. The anti-collapse oil casing pipe according to claim 1, characterized in that it also contains at least one of the following chemical elements: 0<Ni≤0.2%, 0<Cu≤0.2%, 0<Re≤ 0.1%.
7. The collapse-resistant oil casing pipe of claim 1, wherein the microstructure of the collapse-resistant oil casing pipe is tempered sorbite.
8. The collapse-resistant petroleum casing pipe according to any one of claims 1-7, characterized in that its performance index meets at least one of the following items: the yield strength is 965-1173MPa, the tensile strength is ≥1034MPa, Elongation ≥ 20%, fracture toughness K _IC value ≥ 150MPa ^. M ^1/2 , 0°C transverse Charpy impact energy ≥ 120J, ductile brittle transition temperature ≤ -60°C, and collapse resistance performance exceeds API standards by more than 25%.
9. The method for manufacturing a collapse-resistant oil casing pipe according to any one of claims 1-8, characterized in that it comprises the steps of:

   (1) Smelting and continuous casting;

   (2) Perforation;

   (3) Rolling: control the final rolling temperature to 900～950℃, and perform tension reduction after finishing rolling, the temperature is 850～900℃;

   (4) Controlled cooling: on-line water cooling, cooling rate of 15-25℃/s, cooling to 600-650℃, then air cooling to room temperature;

   (5) Quenching + tempering: the quenching temperature is 900～950℃, the holding time is 30～60min; the tempering temperature is 650～700℃, and the holding time is 50～80min;

   (6) Thermal sizing and thermal straightening.
10. The manufacturing method according to claim 9, characterized in that, in step (2), the round billet is soaked at 1260-1290°C, and perforated after soaking, and the perforation temperature is 1180-1240°C.
11. 9. The manufacturing method according to claim 9, wherein in step (1), the continuous casting drawing speed is controlled to be 1.6 to 2.0 m/min.
12. The manufacturing method according to claim 9, wherein in step (6), the heat sizing temperature is 500-550°C.