CN114352211A - Sealing threaded connection assembly method for oil pipe and casing pipe combination - Google Patents
Sealing threaded connection assembly method for oil pipe and casing pipe combination Download PDFInfo
- Publication number
- CN114352211A CN114352211A CN202111591631.1A CN202111591631A CN114352211A CN 114352211 A CN114352211 A CN 114352211A CN 202111591631 A CN202111591631 A CN 202111591631A CN 114352211 A CN114352211 A CN 114352211A
- Authority
- CN
- China
- Prior art keywords
- shoulder
- thread
- assembly
- nipple
- pipe body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000007789 sealing Methods 0.000 title claims abstract description 86
- 238000000034 method Methods 0.000 title claims abstract description 28
- 230000008878 coupling Effects 0.000 claims abstract description 63
- 238000010168 coupling process Methods 0.000 claims abstract description 63
- 238000005859 coupling reaction Methods 0.000 claims abstract description 63
- 210000002445 nipple Anatomy 0.000 claims abstract description 43
- 239000004519 grease Substances 0.000 claims abstract description 37
- 239000002131 composite material Substances 0.000 claims abstract description 31
- 238000012545 processing Methods 0.000 claims abstract description 11
- 239000011248 coating agent Substances 0.000 claims abstract description 6
- 238000000576 coating method Methods 0.000 claims abstract description 6
- 239000002184 metal Substances 0.000 claims description 20
- 230000004323 axial length Effects 0.000 claims description 16
- 239000000463 material Substances 0.000 claims description 5
- 230000007797 corrosion Effects 0.000 claims description 4
- 238000005260 corrosion Methods 0.000 claims description 4
- 210000001331 nose Anatomy 0.000 description 27
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000003245 coal Substances 0.000 description 2
- 238000005536 corrosion prevention Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003345 natural gas Substances 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
Images
Abstract
The invention provides a sealing threaded connection assembly method for an oil pipe and casing combination, which comprises the following steps: s1, arranging external threads, an axial shoulder and a sealing shoulder at the end parts of the two sections of bimetal composite pipe bodies, arranging external threads and a positioning shoulder at the end part of the assembly nipple, processing internal threads on the inner walls of the two ends of the coupling, processing a sealing groove in the middle part, arranging a V-shaped sealing element S2 in the sealing groove, connecting the first end of the coupling with the assembly nipple in a threaded manner, and screwing the threads into the positioning shoulder of the assembly nipple to be contacted with the coupling surface; s3, coating anti-loose fastening oil casing thread grease and anti-thread-sticking oil casing thread grease on the external thread of the first section of the bimetal composite pipe body in a segmented manner, connecting the anti-loose fastening oil casing thread grease and the anti-thread-sticking oil casing thread grease with the second end of the coupling in a threaded manner, and screwing the anti-loose fastening oil casing thread grease and the anti-thread-sticking oil casing thread grease into the end face of the pipe body to be contacted with the end face of the assembly nipple; s4, disassembling the assembly short section; s5, coating anti-sticking oil casing thread grease on the external threads of the second section of the bimetal composite pipe body, connecting the external threads with the first end of the coupling in a threaded manner, and screwing the coupling into contact with the end face of the first section of the bimetal composite pipe body.
Description
Technical Field
The invention relates to the technical field of oil casings for exploration and development of energy sources such as petroleum, natural gas, coal bed gas and the like, in particular to a sealing threaded connection assembling method for an oil pipe and casing combination.
Background
In the exploration and development process of energy sources such as petroleum, natural gas, coal bed gas and the like, oil and casing strings are needed to stabilize a well wall to form an oil-gas channel. At present, the oil and casing strings are often connected in a threaded manner to form the oil and casing strings by single oil and casing pipes, so that the threaded connection has the functions of connection and sealing. The conventional special thread with excellent sealing performance requires high processing precision and large contact pressure of a sealing surface, and particularly when an oil casing is in a stretching state, the contact pressure of the sealing surface is reduced under the action of tensile stress between sealing contacts, so that the sealing effect is influenced, therefore, a special buttress thread buckle type is often adopted, and a sealing thread structure of common/standard API oil and casing threads is not adopted.
Accordingly, there is a need to develop a sealed threaded connection assembly method of tubing and casing combination that addresses the deficiencies of the prior art to address or mitigate one or more of the problems set forth above.
Disclosure of Invention
In view of the above, the invention provides a sealing threaded connection assembly method for an oil pipe and casing combination, which adopts common/standard API oil and casing threads, and overcomes the sealing problems that the opposite threads are loosened by the reaction torque at the factory end, the shoulder surface is not in place, and the tensile load is applied to the connection assembly in the prior art.
The invention provides a sealing threaded connection assembly method for combining an oil pipe and a sleeve, which realizes the connection between opposite-top bimetal composite pipe bodies and comprises the following steps:
s1, processing external threads, an axial shoulder and a sealing shoulder at the end part of two sections of bimetal composite pipe bodies to be connected, processing external threads and a positioning shoulder on an assembly nipple for positioning, processing internal threads on the inner walls of two ends of a connecting coupling, processing a sealing groove in the middle part, and filling a V-shaped sealing element in the sealing groove;
s2, connecting the first end of the connecting coupling with the assembly nipple in a threaded manner, wherein the threaded screwing position reaches the positioning position of the assembly nipple;
s3, coating anti-loose fastening oil casing thread grease and anti-thread-sticking oil casing thread grease on the external thread of the first section of the bimetal composite pipe body in a segmented manner, connecting the anti-loose fastening oil casing thread grease and the anti-thread-sticking oil casing thread grease with the second end thread of the connecting coupling, and screwing the anti-loose fastening oil casing thread grease and the anti-thread-sticking oil casing thread grease into the end face of the pipe body to be in contact with the end face of the assembly nipple;
s4, disassembling the assembly short section;
s5, coating anti-sticking oil casing thread grease on the external threads of the second section of bimetal composite pipe body, connecting the first end of the connecting collar in a threaded manner, and screwing in until the first section of bimetal composite pipe body is in end face contact with the first section of bimetal composite pipe body.
The above aspects and any possible implementation manner further provide an implementation manner, the external threads processed at the end parts of the two sections of bimetal composite pipe bodies are left-handed at the factory assembling end, are right-handed at the field assembling end, are right-handed at the assembling nipple for positioning, are internal threads processed at the inner walls of the two ends of the connecting collar, are left-handed at the factory assembling end, and are right-handed at the field assembling end.
The above aspect and any possible implementation further provide an implementation, in which the V-shaped sealing element is a rubber sealing element, the V-shaped sealing element has an isosceles trapezoid structure as a whole, an inner layer is wide, an outer layer is narrow, a V-shaped opening of the V-shaped sealing element is located on an inner surface of the sealing element, a width of the opening is 1/3 times a width of a bottom surface, and a depth is 1/3 times a thickness of the sealing element.
The aspect and any possible implementation manner described above further provide an implementation manner that the width of the outer surface of the V-shaped rubber sealing element is 2.8-3.2 mm, the width of the inner surface is 0.6-1.2 mm longer than the width of the outer surface, and the thickness is 2.6-3.0 mm.
The above aspects and any possible implementations further provide an implementation where, in step S2, the fitting sub is threaded until the first end face of the connection collar contacts the locating shoulder of the fitting sub.
According to the above aspect and any possible implementation manner, there is further provided an implementation manner, where an external thread is processed at an end of the assembly nipple, a positioning shoulder is arranged on an outer surface of the assembly nipple, and an outer diameter of the positioning shoulder is larger than an outer diameter of the assembly nipple at the external thread; 1/2 the distance between the threaded end face of the fitting nipple and the positioning shoulder is equal to the length of the connecting coupling, and the external thread of the fitting nipple is matched with the internal thread of the connecting coupling;
in step S2, the fitting nipple is threaded until the first end face of the coupling collar contacts the locating shoulder.
The above aspects and any possible implementation manners further provide an implementation manner, the external threads on the two segments of bimetal composite pipe bodies are frustum-shaped, an axial shoulder is machined at the front end of the pipe body, the length of the axial shoulder is 2mm-4mm, a sealing shoulder is machined at the end part of the axial shoulder, the length of the sealing shoulder is 1/2 of the thickness of the outer layer of the V-shaped sealing element, the thickness of the sealing shoulder is 3/8-1/2 of the thickness of the V-shaped sealing element, the thickness of the end face of the pipe body is greater than 1.5mm, and the frustum-shaped external threads of the two segments of bimetal composite pipe bodies are matched with the internal threads of the connecting coupling in the same way.
The above aspects and any possible implementation manners further provide an implementation manner, where each of the two sections of bimetal composite pipe bodies to be connected includes an outer layer metal pipe and an inner layer metal pipe, and the external thread is located on the outer layer metal pipe;
the inner layer metal pipe of the end to be connected protrudes 2mm-4mm compared with the outer layer metal pipe, a corrosion-resistant metal layer is welded on the protruding part of the inner layer metal pipe, and the material of the corrosion-resistant metal layer is fused with the outer layer metal pipe and the inner layer metal pipe.
The above aspects and any possible implementation manners further provide an implementation manner, wherein the inner diameter of the hollow cylindrical section in the coupling collar is greater than the outer diameter of the external thread nose shoulder by 0.1-0.4 mm, the axial length of the hollow cylindrical section is less than 2 times of the axial length of the external thread nose shoulder by 0.2-0.6 mm, the width of the U-shaped sealing groove on the hollow cylindrical section is greater than the width of the outer surface of the sealing element but not more than 0.1mm of the width of the sealing element, and the depth of the U-shaped sealing groove is 3/8-1/2 of the thickness of the sealing element.
In accordance with the foregoing aspect and any one of the possible implementations, there is further provided an implementation in which the contacting of the first end face of the coupling with the positioning shoulder is specifically: and the gap between the first end face of the connecting coupling and the positioning shoulder of the assembling nipple is less than or equal to 0.01 mm.
The above aspect and any possible implementation manner further provide an implementation manner, where the qualification criteria of the external threads of the first section of the bimetal composite pipe body and the second section of the bimetal composite pipe body when screwing in the connection coupling are as follows: the upper buckling torque value reaches a preset value and a nose-shoulder touch signal appears on a torque curve.
Compared with the prior art, one of the technical schemes has the following advantages or beneficial effects:
1): the middle part of the connecting coupling is provided with a sealing groove for assembling a rubber sealing element, and a nose shoulder is processed on the external thread of the pipe body; the nose shoulder is provided with a sealing shoulder surface;
2): the assembly nipple is made of the same material as the pipe body and has a thread structure completely same as the external thread of the pipe body, and a positioning shoulder is machined on the assembly nipple;
3): when assembling the factory end of the threaded connection of the oil and the casing, the assembling positions of the assembling short section and the connecting coupling are controlled through the positioning shoulder on the assembling short section, then anti-thread-sticking oil casing thread grease and locking oil casing thread grease are adopted in different thread sections of the oil and the casing end, and the upper buckling criterion that the upper buckling torque value is in contact combination with the shoulder is adopted, so that the threaded connection position and the torque of the factory end oil casing are accurately controlled, and the accurate assembling and fastening matching of the factory end of the threaded connection of the oil and the casing is realized;
4): the invention has a secondary sealing structure, wherein firstly, contact pressure is formed on a butting contact surface between the nose ends of the external threads of the pipe body through the upper buckling torque, and secondly, contact pressure is formed between a sealing shoulder surface arranged on the nose shoulder of the external threads of the pipe body and a V-shaped rubber sealing element;
5) the left-handed thread and the right-handed thread are respectively adopted at the two ends of the coupling, when the external thread noses at the two sides are in contact with each other, the contact pressure and the friction force are increased along with the increase of the torque, and due to the design of the left-handed thread and the right-handed thread at the two sides of the coupling, the torque generated between the shoulders of the two external thread noses due to the friction force is the screwing-on torque for both the factory end and the field end, so that the unscrewing risk of the whole threaded connection cannot be caused.
6): the special V-shaped structural design of the inner surface of the rubber sealing element has the outstanding advantages that when the opposite contact surfaces between the nose ends of the external thread of the pipe body are separated under tensile load, the hydraulic pressure generated by high-pressure liquid entering the V-shaped space further increases the contact pressure between the sealing shoulder surface on the nose shoulder of the external thread of the pipe body and the V-shaped rubber sealing element, and the higher the hydraulic pressure is, the higher the generated contact pressure is, so that the stable contact pressure is effectively formed between the threaded connection nose shoulders of the pipe serial connection when oil and a sleeve are used on site, the effective assembly is realized, and the integral connection and sealing functions of the whole pipe string are ensured.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of an economical oil and box threaded structure with excellent sealing performance provided by an embodiment of the present invention during assembly;
FIG. 2 is a schematic diagram of a tube structure provided by an embodiment of the present invention;
FIG. 3 is a schematic view of a coupling structure according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a V-shaped rubber seal according to an embodiment of the present invention.
Wherein, in the figure:
1-a pipe body; 2, assembling a short section; 3-connecting a coupling; 4-V rubber seals; 5-anti-loose fastening oil casing thread grease; 6-thread grease of anti-thread sticking oil casing; 1-1-external threads of the pipe; 1-2-external thread nose shoulder; 1-3-sealing shoulder; 2-1-assembling a short section external thread; 2-2-assembling a short section positioning shoulder; 3-1-connecting coupling internal threads; 3-2-connecting the hollow cylindrical section in the coupling; 3-3-connecting the inner seal groove of the coupling.
Detailed Description
For better understanding of the technical solutions of the present invention, the following detailed descriptions of the embodiments of the present invention are provided with reference to the accompanying drawings.
It should be understood that the described embodiments are only some embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Aiming at the problem that the threaded connection part of a bimetal composite pipe in the prior art is easy to corrode, the invention provides an efficient and simple threaded connection structure, and solves the problems that the thread connection at the end of a factory is loosened by counter torque and the shoulder surface is not in place during threaded connection and assembly of a pipe string in a threaded connection on site through accurately controlling the screwing position of the threaded connection at the end of the factory, so that the contact surface at the nose end of the threaded connection forms stable contact pressure, the corrosion prevention problem of the threaded connection part is effectively solved, and the corrosion prevention of the whole pipe string is realized.
A bimetal composite oil and casing threaded connection structure and a factory end assembly method comprise a pipe body, a connection coupling, anti-loose locking thread grease, anti-loose oil casing thread grease, a V-shaped rubber sealing element and an assembly pup joint; an external thread is machined at the end part of the tube body, a nose shoulder is machined at the front end of the external thread, and a sealing step surface is arranged on the nose shoulder; internal threads matched with the external threads of the pipe body are respectively processed at two ends of the connecting coupling, a hollow cylindrical section is processed in the middle of the connecting coupling, and a sealing groove is formed in the inner surface of the cylindrical section; the assembly nipple is an external thread joint with a positioning shoulder, and when the pipe body end is in threaded connection and is connected with a coupling, anti-loosening locking thread grease and anti-loosening oil casing thread grease are required to be used simultaneously. The threads at two ends of the pipe body are API threads or non-API special threads, the section thickness of the nose shoulder at the end part of the pipe body is more than or equal to 2.8mm, the axial length is less than or equal to 4.5mm, the sealing step surface of the nose shoulder at the end part of the pipe body is in a stepped cylindrical shape, the thickness is more than or equal to 1.2mm, the axial length is 1.5mm, the internal thread of the connecting coupling is matched with the external thread on the end surface of the pipe body, the inner diameter of the hollow cylindrical section in the connecting coupling is more than 0.1-0.4 mm of the external diameter of the external thread nose shoulder, the axial length is less than 2 times of the axial length of the external thread nose shoulder and is 0.2-0.6 mm, the depth of the sealing groove on the inner surface of the hollow cylindrical section in the connecting coupling is 1.5mm, the width is 3mm, the assembled and processed nipple has an external thread structure which is completely the same as the end surface of the pipe body, the assembling nipple is processed with a positioning shoulder, the external diameter of the positioning shoulder from the pipe end to 1/2 of the axial length of the connecting coupling, the V-shaped rubber sealing element is of an isosceles trapezoid structure, the inner layer is wide, the outer layer is narrow, a V-shaped opening is formed in the inner surface of the sealing element, the width of the opening is 1/3 of the width of the bottom face, the depth of the opening is 1/3 of the thickness of the sealing element, the width of the outer surface of the V-shaped rubber sealing element is 3mm, the width of the inner surface of the V-shaped rubber sealing element is 3.9mm, the thickness of the V-shaped rubber sealing element is 2.8mm, and the V-shaped rubber sealing element is made of oil-resistant and high-temperature-resistant materials.
The invention relates to a bimetal composite oil, sleeve threaded connection structure and a factory end assembling method, which comprises the following steps:
s1: before the pipe body is in threaded connection with the connecting coupling, a V-shaped rubber sealing element is arranged in the connecting coupling, and then the connecting coupling is in threaded connection with the assembly nipple, so that a positioning shoulder of the assembly nipple is in contact with the end face of the connecting coupling;
s2: anti-thread sticking oil casing thread grease is uniformly smeared on the length of the nose shoulder side 1/2 of the external thread section of the pipe body, the oil casing thread grease is uniformly smeared and locked on the length of the side 1/2 of the thread section pipe body, and the external thread of the pipe body is screwed into the connecting coupling;
s3: when the screwing-on torque value reaches a preset value and a nose shoulder touch signal appears on a torque curve, screwing-on operation of the external thread of the pipe body and the connecting coupling is completed;
s4: and (5) disassembling the assembling short section, and finishing the threaded connection assembling at the factory end.
The assembly nipple described in S1 can be reused many times.
Example 1:
as shown in figure 1, the economical oil and casing thread structure comprises a pipe body 1, an assembly pup joint 2, a connecting coupling 3, a V-shaped rubber sealing element 4, anti-loosening locking thread grease 5 and anti-loosening oil casing thread grease 6; an external thread 1-1 is processed at the end part of the tube body 1, a nose shoulder 1-2 is processed at the front end of the external thread, and a sealing step surface 1-3 is arranged on the nose shoulder; internal threads 3-1 matched with the external threads of the pipe body are respectively processed at two ends of the connecting coupling 3, a hollow cylindrical section 3-2 is processed in the middle of the connecting coupling, and a sealing groove 3-3 is formed in the inner surface of the cylindrical section; the assembly nipple 2 is an external thread joint with a positioning shoulder, and when the pipe body 1 is assembled with the connecting coupling 3, the anti-loosening locking thread grease 5 and the anti-loosening oil casing thread grease 6 are required to be used simultaneously.
In one embodiment, as shown in FIG. 2, the threads 1-1 on both ends of the tube are API threads or non-API special threads, wherein the factory end is left-hand threads and the field end is right-hand threads.
In one embodiment, shown in FIG. 2, the nose shoulder 1-2 of the end of the tube has a cross-sectional thickness of 2.8mm or greater and an axial length of 4.5mm or less.
As shown in figure 2, in one embodiment, the sealing step surface 1-3 of the nose shoulder at the end part of the tube body is in a stepped cylindrical shape, the thickness is more than or equal to 1.2mm, and the axial length is 1.5 mm.
As shown in FIG. 3, in one embodiment, the internal connection collar threads 3-1 mate with the external pipe body end face threads 1-1.
As shown in FIG. 3, in one embodiment, the inner diameter of the hollow cylindrical section 3-2 in the coupling collar is 0.1-0.4 mm larger than the outer diameter of the external thread nose shoulder 1-2, and the axial length is less than 2 times the axial length of the external thread nose shoulder 1-2, and is 0.2-0.6 mm.
As shown in FIG. 3, in one embodiment, the depth of the sealing groove 3-3 on the inner surface of the hollow cylindrical section in the coupling is 1.5mm, and the width is 3 mm.
In one embodiment, as shown in fig. 1, the assembly nipple 2 is provided with a right-handed external thread structure 2-1 which is identical with the end face of the pipe body.
In one embodiment, as shown in figure 1, the fitting sub 2 is machined with a locating shoulder 2-2 having an outer diameter equal to or greater than the outer diameter of the coupling to be joined.
In one particular embodiment, the axial length of the fitting sub from the pipe end to the locating shoulder is 1/2 the axial length of the coupling.
In one embodiment, as shown in fig. 4, the V-shaped rubber seal 4 has an isosceles trapezoid structure, a wide inner layer and a narrow outer layer, the V-shaped opening is located on the inner surface of the seal, the width of the opening is 1/3 of the width of the bottom surface, and the depth is 1/3 of the thickness of the seal.
As shown in FIG. 4, in one embodiment, the V-shaped rubber seal 4 has an outer surface width of 3mm, an inner surface width of 3.9mm, and a thickness of 2.8 mm.
In one embodiment, as shown in fig. 4, the V-shaped rubber seal 4 is made of an oil-resistant and high-temperature-resistant material.
As shown in fig. 1, in a specific embodiment, an economical oil and casing thread structure and a factory end assembly method, before a pipe body 1 is in threaded connection with a connecting coupling 3, a V-shaped rubber sealing element 4 is arranged in the connecting coupling 3, and then the connecting coupling 3 is in threaded connection with an assembly nipple 2, so that a positioning shoulder 2-2 of the assembly nipple is in contact with the end face of the connecting coupling;
in one embodiment, as shown in fig. 1, an economical oil, casing thread structure and factory-end assembly method, anti-galling oil casing thread grease 6 is uniformly applied to the length of the nose-shoulder side 1/2 of the external thread section 1-1 of the pipe body, oil casing thread grease 5 is uniformly applied and locked to the length of the pipe body side 1/2, and the external thread 1-1 of the pipe body is screwed into the coupling 3;
as shown in fig. 1, in an embodiment, an economical oil, casing thread structure and a factory-side assembly method, when a make-up torque value reaches a preset value and a nose-shoulder touch signal appears on a torque curve, make-up operation of an external thread of a pipe body 1 and a connection coupling 3 is completed;
in one embodiment, an economical oil and casing threaded structure and a factory end assembly method, as shown in fig. 1, the assembly nipple 2 is removed and the factory end threaded connection is assembled.
In one embodiment, an economical oil, casing thread structure and a factory end assembly method, an assembly nipple can be reused for multiple times.
The above provides a detailed description of the method for assembling a sealed threaded connection of an oil pipe and casing combination according to the embodiment of the present application. The above description of the embodiments is only for the purpose of helping to understand the method of the present application and its core ideas; meanwhile, for a person skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.
It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element. "substantially" means within an acceptable error range, and a person skilled in the art can solve the technical problem within a certain error range to substantially achieve the technical effect.
The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. In the present application, the terms "upper", "lower", "left", "right", "inner", "outer", "middle", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. Some of the above terms may be used to indicate other meanings in addition to orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of dependency or connection relationship in some cases. The specific meaning of these terms in this application will be understood by those of ordinary skill in the art as appropriate. The term "and/or" as used herein is merely an associative relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.
Claims (10)
1. A sealing threaded connection assembly method for combining an oil pipe and a sleeve pipe realizes the connection between opposite-top bimetal composite pipe bodies, and is characterized in that the sealing threaded connection assembly method comprises the following steps:
s1, processing external threads, an axial shoulder and a sealing shoulder at the end part of two sections of bimetal composite pipe bodies to be connected, processing external threads and a positioning shoulder on an assembly nipple for positioning, processing internal threads on the inner walls of two ends of a connecting coupling, processing a sealing groove in the middle part, and filling a V-shaped sealing element in the sealing groove;
s2, connecting the first end of the connecting coupling with the assembly nipple in a threaded manner, wherein the threaded screwing position reaches the positioning position of the assembly nipple;
s3, coating anti-loose fastening oil casing thread grease and anti-thread-sticking oil casing thread grease on the external thread of the first section of the bimetal composite pipe body in a segmented manner, connecting the anti-loose fastening oil casing thread grease and the anti-thread-sticking oil casing thread grease with the second end thread of the connecting coupling, and screwing the anti-loose fastening oil casing thread grease and the anti-thread-sticking oil casing thread grease into the end face of the pipe body to be in contact with the end face of the assembly nipple;
s4, disassembling the assembly short section;
s5, coating anti-sticking oil casing thread grease on the external threads of the second section of bimetal composite pipe body, connecting the first end of the connecting collar in a threaded manner, and screwing in until the first section of bimetal composite pipe body is in end face contact with the first section of bimetal composite pipe body.
2. The assembly method of claim 1, wherein the external threads formed on the ends of the two sections of the bimetal composite pipe body are left-handed and right-handed, the external threads formed on the assembly nipple for positioning are right-handed, the internal threads formed on the inner walls of the two ends of the coupling are connected, the left-handed end is the factory assembly end, and the right-handed end is the field assembly end.
3. The method of assembling a sealed threaded connection of claim 1, wherein the V-shaped seal is a rubber seal, the V-shaped seal has an isosceles trapezoid structure, an inner layer is wide, an outer layer is narrow, the V-shaped opening of the V-shaped seal is located on the inner surface of the seal, the width of the opening is 1/3 of the width of the bottom surface, and the depth is 1/3 of the thickness of the seal.
4. The method of assembling a sealed threaded connection according to claim 2, wherein the width of the outer surface of the V-shaped rubber seal is 2.8 to 3.2mm, the width of the inner surface is 0.6 to 1.2mm longer than the width of the outer surface, and the thickness is 2.6 to 3.0 mm.
5. The sealed threaded connection makeup method of claim 1, wherein in step S2, said makeup nipple is threaded until a first end face of said connection collar contacts a locating shoulder of said makeup nipple.
6. The sealed threaded connection assembly method of claim 4, wherein an external thread is machined at the end of the assembly nipple, a positioning shoulder is arranged on the outer surface of the assembly nipple, and the outer diameter of the positioning shoulder is larger than that of the external thread of the assembly nipple; the distance between the threaded end face of the assembly nipple and the positioning shoulder is equal to 1/2 the length of the connecting coupling, and the external threads of the assembly nipple are matched with the internal threads of the connecting coupling.
7. The assembly method of claim 1, wherein the external thread of the two segments of bimetal composite pipe bodies is in a frustum shape, an axial shoulder is machined at the front end of the pipe body, the length of the axial shoulder is 2mm-4mm, a sealing shoulder is machined at the end part of the axial shoulder, the length of the sealing shoulder is 1/2 of the thickness of the outer layer of the V-shaped sealing element, the thickness of the sealing shoulder is 3/8-1/2 of the thickness of the V-shaped sealing element, the thickness of the end face of the pipe body is more than 1.5mm, and the frustum-shaped external thread of the two segments of bimetal composite pipe bodies is matched with the internal thread of the connecting collar in the same way.
8. The sealed threaded connection assembly method of claim 1, wherein the two sections of bimetallic composite pipe bodies to be connected each comprise an outer layer metal pipe and an inner layer metal pipe, and the external threads are located on the outer layer metal pipe;
the inner layer metal pipe of the end to be connected protrudes 2mm-4mm compared with the outer layer metal pipe, a corrosion-resistant metal layer is welded on the protruding part of the inner layer metal pipe, and the material of the corrosion-resistant metal layer is fused with the outer layer metal pipe and the inner layer metal pipe.
9. The assembly method of claim 6, wherein the inner diameter of the hollow cylindrical section in the coupling collar is 0.1-0.4 mm larger than the outer diameter of the external thread nose shoulder, the axial length is less than 2 times the axial length of the external thread nose shoulder, the axial length of the external thread nose shoulder is 0.2-0.6 mm, the width of the U-shaped sealing groove on the hollow cylindrical section is larger than the width of the outer surface of the sealing element but not more than 0.1mm of the width of the sealing element, and the depth of the U-shaped sealing groove is 3/8-1/2 of the thickness of the sealing element.
10. The sealed threaded connection make-up method of claim 4, wherein the contacting of the first end face of the connection collar with the locating shoulder is specifically: the clearance between the first end face of the connecting coupling and the positioning shoulder of the assembling nipple is less than or equal to 0.01mm, and the qualified criteria of the external threads of the first section of bimetal composite pipe body and the second section of bimetal composite pipe body in screwing in the connecting coupling are as follows: the upper buckling torque value reaches a preset value and a nose-shoulder touch signal appears on a torque curve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111591631.1A CN114352211A (en) | 2021-12-23 | 2021-12-23 | Sealing threaded connection assembly method for oil pipe and casing pipe combination |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111591631.1A CN114352211A (en) | 2021-12-23 | 2021-12-23 | Sealing threaded connection assembly method for oil pipe and casing pipe combination |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114352211A true CN114352211A (en) | 2022-04-15 |
Family
ID=81100759
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111591631.1A Pending CN114352211A (en) | 2021-12-23 | 2021-12-23 | Sealing threaded connection assembly method for oil pipe and casing pipe combination |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114352211A (en) |
Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0212288A2 (en) * | 1985-08-19 | 1987-03-04 | George M. Raulins | Improved oilfield tubular joint and method of manufacturing |
| JPH08320091A (en) * | 1995-05-24 | 1996-12-03 | Nippon Steel Corp | Oil well tubing thread coupling |
| CN1292058A (en) * | 1998-03-26 | 2001-04-18 | 法国瓦罗里克·曼尼斯曼油汽公司 | Threaded assembly of metal tubes designed to contain corrosive fluid |
| CN2744914Y (en) * | 2004-03-10 | 2005-12-07 | 天津钢管有限责任公司 | Screwed joint structure with wedge shape sealing ring |
| JP2006112594A (en) * | 2004-10-18 | 2006-04-27 | Daido Steel Co Ltd | Metal covering steel pipe screw joint |
| CN201982024U (en) * | 2010-12-08 | 2011-09-21 | 中国石油集团石油管工程技术研究院 | Casing gas seal screwed nipples for gas well |
| CN103015940A (en) * | 2011-09-23 | 2013-04-03 | 韦特柯格雷公司 | Rotationally actuated riser tubular connection |
| CN204647602U (en) * | 2015-05-19 | 2015-09-16 | 中国重型机械研究院股份公司 | A kind of composite bimetal pipe pipe end linkage structure |
| CN105888572A (en) * | 2016-06-21 | 2016-08-24 | 东营威玛石油钻具有限公司 | Double-shoulder drilling tool screwed joint |
| CN110043196A (en) * | 2019-04-11 | 2019-07-23 | 中国石油天然气集团有限公司 | A kind of oil well pipe male connection end face seal coil structures and its assembly method |
| CN110130839A (en) * | 2019-04-30 | 2019-08-16 | 中国石油天然气集团有限公司 | A kind of ring seal structure of coupling |
| US20190316712A1 (en) * | 2016-12-23 | 2019-10-17 | Evolution Engineering Inc. | Sealed gap sub |
| CN110529055A (en) * | 2019-08-30 | 2019-12-03 | 江苏璞腾油气装备有限公司 | A kind of high antitorque air-tight oil casing nipple |
| CN114087459A (en) * | 2021-11-22 | 2022-02-25 | 西安德信成科技有限责任公司 | End-to-end connection method for pipelines with inner corrosion-resistant layers |
| CN114658371A (en) * | 2021-10-20 | 2022-06-24 | 西安德信成科技有限责任公司 | Oil pipe and sleeve combined sealing thread structure and factory end assembling method |
| CN217632307U (en) * | 2021-12-23 | 2022-10-21 | 西安德信成科技有限责任公司 | Economical oil and casing thread structure |
-
2021
- 2021-12-23 CN CN202111591631.1A patent/CN114352211A/en active Pending
Patent Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0212288A2 (en) * | 1985-08-19 | 1987-03-04 | George M. Raulins | Improved oilfield tubular joint and method of manufacturing |
| JPH08320091A (en) * | 1995-05-24 | 1996-12-03 | Nippon Steel Corp | Oil well tubing thread coupling |
| CN1292058A (en) * | 1998-03-26 | 2001-04-18 | 法国瓦罗里克·曼尼斯曼油汽公司 | Threaded assembly of metal tubes designed to contain corrosive fluid |
| CN2744914Y (en) * | 2004-03-10 | 2005-12-07 | 天津钢管有限责任公司 | Screwed joint structure with wedge shape sealing ring |
| JP2006112594A (en) * | 2004-10-18 | 2006-04-27 | Daido Steel Co Ltd | Metal covering steel pipe screw joint |
| CN201982024U (en) * | 2010-12-08 | 2011-09-21 | 中国石油集团石油管工程技术研究院 | Casing gas seal screwed nipples for gas well |
| CN103015940A (en) * | 2011-09-23 | 2013-04-03 | 韦特柯格雷公司 | Rotationally actuated riser tubular connection |
| CN204647602U (en) * | 2015-05-19 | 2015-09-16 | 中国重型机械研究院股份公司 | A kind of composite bimetal pipe pipe end linkage structure |
| CN105888572A (en) * | 2016-06-21 | 2016-08-24 | 东营威玛石油钻具有限公司 | Double-shoulder drilling tool screwed joint |
| US20190316712A1 (en) * | 2016-12-23 | 2019-10-17 | Evolution Engineering Inc. | Sealed gap sub |
| CN110043196A (en) * | 2019-04-11 | 2019-07-23 | 中国石油天然气集团有限公司 | A kind of oil well pipe male connection end face seal coil structures and its assembly method |
| CN110130839A (en) * | 2019-04-30 | 2019-08-16 | 中国石油天然气集团有限公司 | A kind of ring seal structure of coupling |
| CN110529055A (en) * | 2019-08-30 | 2019-12-03 | 江苏璞腾油气装备有限公司 | A kind of high antitorque air-tight oil casing nipple |
| CN114658371A (en) * | 2021-10-20 | 2022-06-24 | 西安德信成科技有限责任公司 | Oil pipe and sleeve combined sealing thread structure and factory end assembling method |
| CN114087459A (en) * | 2021-11-22 | 2022-02-25 | 西安德信成科技有限责任公司 | End-to-end connection method for pipelines with inner corrosion-resistant layers |
| CN217632307U (en) * | 2021-12-23 | 2022-10-21 | 西安德信成科技有限责任公司 | Economical oil and casing thread structure |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| RU2522756C1 (en) | Threaded joint for pipes | |
| CA2418920C (en) | Screw threaded joint for continuous-profile tubes | |
| US4662659A (en) | Tubular joint with trapped mid-joint metal-to-metal seal having unequal tapers | |
| US5358289A (en) | Buttress-threaded tubular connection | |
| US4384737A (en) | Threaded joint for well casing and tubing | |
| JP4257707B2 (en) | Threaded fitting | |
| AU2006215573B2 (en) | Threaded joint for pipes provided with seal | |
| JP3808562B2 (en) | Pipe threaded joints | |
| EP0131621B1 (en) | Tubular joint with trapped mid-joint metal to metal seal | |
| CA2827619C (en) | Threaded joint for pipes | |
| AU2017202254B2 (en) | Tubular connection center shoulder seal | |
| US6073332A (en) | Corrosion resistant tubular system and method of manufacture thereof | |
| CA2691104C (en) | A method and apparatus for inhibiting corrosion in strings of tubulars | |
| MX2011004112A (en) | Threaded joint for steel pipes. | |
| GB2098689A (en) | Threaded pin and box joint | |
| WO2017069030A1 (en) | Threaded fitting for steel pipes | |
| EP3259436B1 (en) | Threaded connection for pipes, such as oil and gas pipes | |
| RU2764344C2 (en) | Curved sealing system | |
| RU2661917C1 (en) | Tubular threaded connection | |
| CN103238017B (en) | A kind of sealing of improvement of pipeline enclosure | |
| EA000129B1 (en) | Screw connection for internally coated metal pipes | |
| RU2398153C1 (en) | Sealed threaded connection of oil-field pipelines | |
| CN217632307U (en) | Economical oil and casing thread structure | |
| CN114352211A (en) | Sealing threaded connection assembly method for oil pipe and casing pipe combination | |
| US8740259B2 (en) | Internally lined pipe connections and related methods of makeup |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |