WO2017213048A1 - 鋼管用ねじ継手 - Google Patents
鋼管用ねじ継手 Download PDFInfo
- Publication number
- WO2017213048A1 WO2017213048A1 PCT/JP2017/020651 JP2017020651W WO2017213048A1 WO 2017213048 A1 WO2017213048 A1 WO 2017213048A1 JP 2017020651 W JP2017020651 W JP 2017020651W WO 2017213048 A1 WO2017213048 A1 WO 2017213048A1
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- WIPO (PCT)
- Prior art keywords
- pin
- box
- seal surface
- thread
- threaded joint
- Prior art date
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- 239000010959 steel Substances 0.000 title claims abstract description 55
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- 239000002343 natural gas well Substances 0.000 description 1
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Images
Classifications
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/042—Threaded
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L15/00—Screw-threaded joints; Forms of screw-threads for such joints
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L15/00—Screw-threaded joints; Forms of screw-threads for such joints
- F16L15/001—Screw-threaded joints; Forms of screw-threads for such joints with conical threads
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L15/00—Screw-threaded joints; Forms of screw-threads for such joints
- F16L15/04—Screw-threaded joints; Forms of screw-threads for such joints with additional sealings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L15/00—Screw-threaded joints; Forms of screw-threads for such joints
- F16L15/06—Screw-threaded joints; Forms of screw-threads for such joints characterised by the shape of the screw-thread
Definitions
- This disclosure relates to a threaded joint used for connecting steel pipes.
- oil wells For example, exploration or production of oil wells and natural gas wells (hereinafter collectively referred to as “oil wells”), development of unconventional resources such as oil sands and shale gas, carbon dioxide recovery and storage (CCS (Carbon Dioxide Capture and Storage)), geothermal power generation, or hot springs use steel pipes called oil well pipes. A threaded joint is used for the connection between the steel pipes.
- This type of threaded joint for steel pipes is roughly divided into a coupling type and an integral type.
- the coupling type one of the pair of pipes to be connected is a steel pipe, and the other pipe is a coupling.
- male screw portions are formed on the outer periphery of both ends of the steel pipe
- female screw portions are formed on the inner periphery of both ends of the coupling.
- the external thread part of a steel pipe is screwed in the internal thread part of a coupling, and both are fastened by this and are connected.
- both of the pair of pipes to be connected are steel pipes, and no separate coupling is used.
- a male thread part is formed in the outer periphery of the one end part of a steel pipe, and a female thread part is formed in the inner periphery of the other end part.
- the external thread part of one steel pipe is screwed in the internal thread part of the other steel pipe, and both are fastened and connected by this.
- the joint portion of the pipe end portion where the male screw portion is formed includes an element inserted into the female screw portion, and is therefore referred to as a pin.
- the joint portion of the pipe end portion where the female thread portion is formed includes an element that receives the male thread portion, and is therefore referred to as a box. Since these pins and boxes are the ends of the pipe material, they are both tubular.
- the result is a structure in which the oil well pipes are arranged in multiple layers.
- the inner and outer diameters of the joints are connected to the well pipes. Threaded joints that are comparable to the inner and outer diameters are often used. By using such a threaded joint, the gaps between the oil well pipes arranged in multiple can be made as small as possible, and even if deep, the well diameter is not so large and the oil well can be efficiently developed.
- the threaded joint has a pressure fluid from the inside (hereinafter also referred to as “internal pressure”) and a pressure fluid from the outside (hereinafter also referred to as “external pressure”). Excellent sealing performance is required.
- the seal part by metal-metal contact described here has a slightly larger diameter of the seal surface of the pin than the diameter of the seal surface of the box (this difference in diameter is called the amount of interference).
- the seal surface of the pin shrinks due to the amount of interference
- the seal surface of the box expands, and the contact pressure is applied to the seal surface by the elastic recovery force that each seal surface tries to return to its original diameter. Is generated, the entire circumference adheres closely, and the sealing performance is exhibited.
- Examples of threaded joints in which the inner diameter and outer diameter of the joint portion are approximately the same as the inner diameter and outer diameter of the steel pipe are, for example, flash type, semi-flash type, slim type, and special clearance type (hereinafter collectively referred to as “slim type”). And so on.
- slim type threaded joints the inner and outer diameters are strictly limited, so that the thickness of the tip of the pin where the sealing surface for internal pressure (sealing surface in the pin) is provided is small, and the elasticity of the sealing surface in the pin Resilience cannot be made large enough.
- FIG. 1 of European Patent No. 1836426 and FIGS. 1 and 2 of US Pat. No. 4,795,200 disclose a screw joint in which a nose portion is provided at the tip of a pin.
- the nose part has a function of amplifying the elastic recovery force of the seal surface in the pin because it does not interfere with the box. That is, since the adhesion between the sealing surface in the pin and the sealing surface in the box is amplified by the nose portion, the sealing performance against the internal pressure is improved.
- the sealing performance against internal pressure can be improved.
- the thickness of the nose portion becomes very small due to dimensional restrictions, and there is a possibility that sufficient sealing performance against internal pressure cannot be ensured.
- Increasing the thickness of the tip of the pin to improve the sealing performance against internal pressure increases the diameter of the other parts of the pin, that is, the male thread and the outer seal, which will be described later, resulting in the outer diameter of the joint. Due to this restriction, the thickness of the box on the opposite side is generally reduced, the thickness of the outer seal portion on the box side is also reduced, and the sealing performance against external pressure is reduced.
- This disclosure aims to provide a threaded joint for steel pipes that can improve the sealing performance against the internal pressure without reducing the sealing performance against the external pressure.
- a threaded joint for steel pipes includes a tubular pin and a tubular box.
- the box has an outer diameter that is less than 108% of the outer diameter of the steel pipe body.
- the box is fastened to the pin by inserting the pin.
- the pin includes a pin lip portion, a pin shoulder surface, a male screw portion, and a pin outer seal surface.
- the pin lip portion includes an in-pin seal surface and a nose portion.
- the pin inner seal surface is provided on the outer peripheral surface of the tip of the pin.
- a nose part is provided in the front end side of a pin rather than the sealing surface in a pin.
- the outer peripheral surface of the nose portion has a diameter smaller than the diameter of the inner peripheral surface of the opposing box.
- the outer peripheral surface of the nose portion has a shape discontinuous with the shape of the seal surface in the pin.
- the pin shoulder surface is provided at the end of the pin on the steel pipe main body side.
- the male thread portion is provided on the outer periphery of the pin between the pin lip portion and the pin shoulder surface.
- the male screw portion is formed by a taper screw having a dovetail shape.
- the pin outer seal surface is provided on the outer peripheral surface of the pin between the pin lip portion and the pin shoulder surface.
- the box includes a box inner seal surface, a box shoulder surface, a female thread portion, and a box outer seal surface.
- the box seal surface is provided on the inner peripheral surface of the box corresponding to the pin seal surface.
- the in-box seal surface comes into contact with the in-pin seal surface in the fastened state.
- the box shoulder surface is provided on the end surface of the box corresponding to the pin shoulder surface.
- the box shoulder surface contacts the pin shoulder surface in the fastened state.
- the female screw portion is provided on the inner periphery of the box corresponding to the male screw portion.
- the female screw portion is configured by a taper screw having a dovetail shape.
- the female screw portion has an insertion flank surface that is opposed to the insertion flank surface of the male screw portion with a gap in the fastened state.
- the box outer seal surface is provided on the inner peripheral surface of the box corresponding to the pin outer seal surface. The box outer seal surface is in contact with the pin outer seal surface in the fastened state.
- the sealing performance against the internal pressure can be improved without reducing the sealing performance against the external pressure.
- FIG. 1 is a longitudinal section showing the schematic structure of the threaded joint for steel pipes concerning an embodiment.
- FIG. 2 is an enlarged view of a threaded portion of the threaded joint shown in FIG.
- FIG. 3 is an enlarged view of the inner end portion of the threaded joint shown in FIG. 1 in the tube axis direction.
- FIG. 4 is an enlarged view of a threaded portion of the threaded joint shown in FIG.
- FIG. 5 is a longitudinal sectional view of a conventional threaded joint for steel pipes.
- the inner seal portion is generally provided at the inner end of the threaded joint in the tube axis direction. That is, the inner seal portion is often arranged inside the screw portion in the tube axis direction.
- the inner seal portion is constituted by a pin inner seal surface and a box inner seal surface.
- the in-pin seal surface is provided on the outer peripheral surface of the pin lip portion constituting the tip portion of the pin.
- an inner seal portion at the inner end portion of the threaded joint in the tube axis direction in addition to the amplification of the adhesion force due to the internal pressure load.
- a lubricant may be applied to the surface of the thread portion and / or the surface of the seal portion.
- the inner seal portion on the inner side in the tube axis direction than the screw portion, it is possible to prevent the internal fluid such as crude oil or natural gas from entering the screw portion. Therefore, it is possible to prevent crevice corrosion from occurring due to the internal fluid that has entered the narrow gap of the threaded portion, thereby preventing a hole from being formed in the threaded portion or the threaded portion from being broken.
- the wall thickness of the pin lip portion where the inner seal surface is provided must be very small. For this reason, even if the interference amount of the inner seal portion is increased, the elastic recovery force of the pin inner seal surface is not greatly amplified. Therefore, in the slim type threaded joint, even if the effect of the internal pressure load acting on the inner peripheral surface of the pin lip portion is added, the adhesion force of the seal surface in the pin to the seal surface in the box is not greatly amplified, and the internal pressure The sealing performance against can not be improved significantly.
- the sealing performance against the internal pressure does not mean the sealing performance in a state where only the internal pressure load is applied.
- Sealing performance against internal pressure means that, in addition to internal pressure load, various loads assumed in actual use, such as tensile and compression in the tube axis direction, bending, external pressure load, etc., are repeatedly applied or loaded. It means the later sealing performance.
- As a method for evaluating the sealing performance of a threaded joint under repeated composite loads with a substantial sample for example, there are evaluation tests defined by API5C5 and ISO13679.
- the nose part is configured not to interfere with the box.
- the nose portion has a function of amplifying an elastic recovery force in which the pin inner seal surface reduced in diameter due to interference with the box inner seal surface attempts to return to the original diameter. Therefore, if the nose portion is provided in the pin lip portion, it is considered that the adhesion force of the inner seal portion is amplified and the sealing performance against the internal pressure is improved without increasing the amount of interference of the inner seal portion.
- the adhesion of the inner seal portion cannot be greatly amplified simply by providing a nose portion at the pin lip portion. This is because in the slim type threaded joint, the wall thickness of the nose portion becomes very small due to the size limitation.
- the nose portion does not interfere with the box, an internal pressure load acts on both the inner peripheral surface and the outer peripheral surface.
- the nose portion is intended to stay in place when an internal pressure load is applied, and does not have an effect of amplifying the adhesion force due to the internal pressure load.
- the rigidity of the pin lip portion is increased and deformation of the pin lip portion is less likely to occur.
- the effect of amplifying the adhesion force due to the load of the internal pressure which is obtained by ensuring the distance between the threaded portion and the pin inner seal surface, is reduced.
- the distance in the tube axis direction between the screw portion and the pin inner seal surface and the length in the tube axis direction of the nose portion is important. However, the balance is not considered in the conventional slim type threaded joint.
- the wall thickness of the pin lip is small due to dimensional constraints. For this reason, when an internal pressure load acts on the inner surface of the pin lip portion, the portion between the screw portion and the pin inner seal surface swells to the outer peripheral side, and the pin inner seal surface is inclined with respect to the box inner seal surface. According to the study by the inventors, the inclination of the seal surface in the pin increases as the distance in the tube axis direction between the thread portion and the seal surface in the pin increases. If the seal surface in the pin is inclined with respect to the seal surface in the box, the contact position between the seal surface in the pin and the seal surface in the box moves, and the sealing performance against internal pressure becomes unstable. That is, the contact position between the seal surface in the pin and the seal surface in the box is deviated from the familiar position due to sliding during fastening, and there is a high possibility that internal fluid leaks.
- the movement of the contact position between the seal surface in the pin and the seal surface in the box, or the displacement in the tube axis direction of the seal surface in the pin and / or the seal surface in the box also occurs due to a compression load. Since the slim type threaded joint has a relatively large diameter and a thin wall, the relative displacement between the pin and the box caused by the compression load is larger than that of other types of threaded joints. In order to improve the sealing performance, it is necessary to suppress such relative displacement between the pin and the box.
- the screw that can minimize the relative displacement between the pin and the box due to the compressive load is of a type in which the insertion flank surface of the male screw and the insertion flank surface of the female screw are in contact with each other in the fastened state. If each insertion flank surface has a negative angle, that is, a shape inclined to the tip end side of the pin with respect to a surface perpendicular to the tube axis direction, the relative displacement between the pin and the box can be further reduced.
- a typical example is a screw having a screw width that gradually changes along the lead and having a dovetail shape in cross section (hereinafter referred to as a dovetail screw).
- the dovetail screw generally has a self-tightening action. For this reason, the threaded joint to which the dovetail screw is applied usually does not have a shoulder portion for restricting screwing of the pin into the box.
- Threaded joints to which dovetail screws are applied come into contact with each other between the insert flank surfaces and the load flank surfaces, and the male screw and the female screw are fitted together to complete the fastening.
- the position where the fastening is completed may change greatly due to a lead error, an angle error of the insertion flank surface and / or a load flank surface, an elliptic error, a screw width error, or the like. Therefore, it is difficult to stably introduce the interference amount of the seal portion, and the sealing performance becomes unstable.
- the screw can reduce the relative displacement between the pin and the box, and the cross-sectional shape is a dovetail shape, and the insertion flank surface of the male screw and the insertion flank surface of the female screw are in a fastened state. Some have gaps between them.
- the designers can reduce the relative displacement between the pin and the box, which tends to be large in the slim type threaded joint, without adverse effects, and stable sealing performance. Thought it could be obtained.
- the screw joint in which a gap is formed between the insertion flank surface of the male screw and the insertion flank surface of the female screw in the fastened state is less susceptible to the various errors described above. Moreover, if a shoulder part is provided in this threaded joint, the completion position of fastening can be managed by the shoulder part. Therefore, it can suppress that the completion position of fastening changes, and the amount of interference of a seal part can be stabilized, and sealing performance can be stabilized.
- the inventors devised a threaded joint for steel pipes that can improve the sealing performance against internal pressure while maintaining the sealing performance against external pressure.
- the threaded joint for steel pipes includes a tubular pin and a tubular box.
- the box has an outer diameter that is less than 108% of the outer diameter of the steel pipe body.
- the box is fastened to the pin by inserting the pin.
- the pin includes a pin lip portion, a pin shoulder surface, a male screw portion, and a pin outer seal surface.
- the pin lip portion includes an in-pin seal surface and a nose portion.
- the pin inner seal surface is provided on the outer peripheral surface of the tip of the pin.
- a nose part is provided in the front end side of a pin rather than the sealing surface in a pin.
- the outer peripheral surface of the nose portion has a diameter smaller than the diameter of the inner peripheral surface of the opposing box.
- the outer peripheral surface of the nose portion has a shape discontinuous with the shape of the seal surface in the pin.
- the pin shoulder surface is provided at the end of the pin on the steel pipe main body side.
- the male thread portion is provided on the outer periphery of the pin between the pin lip portion and the pin shoulder surface.
- the male screw portion is formed by a taper screw having a dovetail shape.
- the pin outer seal surface is provided on the outer peripheral surface of the pin between the pin lip portion and the pin shoulder surface.
- the box includes a box inner seal surface, a box shoulder surface, a female thread portion, and a box outer seal surface.
- the box seal surface is provided on the inner peripheral surface of the box corresponding to the pin seal surface.
- the in-box seal surface comes into contact with the in-pin seal surface in the fastened state.
- the box shoulder surface is provided on the end surface of the box corresponding to the pin shoulder surface.
- the box shoulder surface contacts the pin shoulder surface in the fastened state.
- the female screw portion is provided on the inner periphery of the box corresponding to the male screw portion.
- the female screw portion is configured by a taper screw having a dovetail shape.
- the female thread portion has an insertion flank surface facing the insertion flank surface of the male screw portion with a gap in the fastened state.
- the box outer seal surface is provided on the inner peripheral surface of the box corresponding to the pin outer seal surface. The box outer seal surface is in contact with the pin outer seal surface in the fastened state.
- the distance D in the tube axis direction between the male screw portion and the seal surface in the pin is 1.5 times or more the screw pitch P of the male screw portion.
- the length L of the nose portion in the tube axis direction is larger than the screw pitch P.
- the difference between the distance D between the male screw portion and the sealing surface in the pin and the length L of the nose portion is within the screw pitch P.
- the nose portion is provided in the pin lip portion, the bending rigidity of the pin lip portion is large and the pin lip portion is hardly deformed. Therefore, it is possible to suppress the in-pin seal surface from being inclined with respect to the in-box seal surface due to the internal pressure load. For this reason, the movement of the contact position between the seal surface in the pin and the seal surface in the box is suppressed, and the deterioration of the sealing performance against the internal pressure can be prevented.
- each of the male screw portion and the female screw portion is constituted by a taper screw having a dovetail shape. Since a gap is formed between the insertion flank surface of the male screw portion and the insertion flank surface of the female screw portion in the fastened state, the screw joint is not easily affected by various errors. Moreover, the completion position of fastening can be stabilized by a pin shoulder surface and a box shoulder surface contacting in a fastening state. Therefore, the interference amount of the seal portion can be stably introduced, and the sealing performance against the internal pressure and the external pressure can be stabilized.
- the sealing performance against the internal pressure can be improved without reducing the sealing performance against the external pressure.
- the inner sealing surface of the pin can be a convex surface including a tapered surface that decreases in diameter toward the tip end side of the pin and an arc surface that is continuous with both ends of the tapered surface.
- the box inner seal surface may include a tapered surface longer than the pin inner seal surface (second configuration).
- the seal surface in the pin is composed of a single circular arc surface having a large radius of curvature.
- the shape of the seal surface in the pin is the cause of the large movement of the contact position between the seal surface in the pin and the seal surface in the box when the seal surface in the pin is inclined with respect to the seal surface in the box due to the internal pressure load. Become.
- the seal surface in the pin is composed of a tapered surface and an arc surface having a relatively small radius of curvature that is continuous with both ends of the tapered surface.
- the taper surface of the seal surface in the pin slides in contact with the taper surface of the seal surface in the box, and after the final stage of the fastening and the completion of the fastening, The arc surface comes into contact with the tapered surface of the seal surface in the box.
- the radius of curvature of the arc surface may be 3 mm to 30 mm (third configuration).
- the pin outer seal surface may be arranged at the end of the pin on the steel pipe main body side (fourth configuration).
- the screw portion constituted by the male screw portion and the female screw portion is arranged between the inner seal portion and the outer seal portion.
- the screw portion can be constituted by a single stage screw. In this case, since the thickness that can be used for the threaded portion is increased, the complete threaded portion region can be sufficiently secured. As a result, a decrease in the tensile strength of the screw connection can be suppressed, and the joint strength can be ensured.
- the distance D may be three times or less of the screw pitch P (fifth configuration).
- the pin lip portion does not become too long, and the material cost and / or the manufacturing cost can be reduced.
- the screw portion constituted by the male screw portion and the female screw portion may have a screw width that varies along the lead (sixth configuration).
- the gap between the insertion flank surface of the male screw portion and the insertion flank surface of the female screw portion is large, and the gap becomes small immediately before the completion of the fastening. For this reason, seizure is less likely to occur as compared with a threaded joint having a thread portion with a constant thread width and having a small gap between the insertion flank surfaces even during fastening.
- the gap between the insertion flank surface of the male screw portion and the insertion flank surface of the female screw portion may be 100 ⁇ m or less (seventh configuration).
- the thread portion composed of the male thread portion and the female thread portion may be a single thread or a double thread (eighth configuration).
- FIG. 1 is a longitudinal sectional view showing a schematic configuration of a threaded joint 1 for steel pipes according to an embodiment.
- the threaded joint 1 is an integral type threaded joint. However, the threaded joint 1 can also be applied to a coupling type.
- the threaded joint 1 includes a tubular pin 10 and a box 20, respectively.
- the pin 10 is inserted into the box 20 and the pin 10 and the box 20 are fastened.
- the threaded joint 1 is a slim type with a small difference between the outer diameter of the joint and the outer diameter of the steel pipe.
- the outer diameter of the box 20 is smaller than 108% of the outer diameter of the steel pipe body of the pin 10.
- the outer diameter of the box 20 is 100% or more of the outer diameter of the steel pipe body of the pin 10.
- the inner diameter of the pin 10 is larger than the drift diameter defined by the API (American Petroleum Institute) standard.
- the steel pipe body of the pin 10 refers to a portion of the steel pipe including the pin 10 that is not inserted into the box 20.
- the tip side of the pin 10 may be referred to as the inner side in the tube axis direction
- the steel pipe main body side of the pin 10 may be referred to as the outer side in the tube axis direction.
- the pin 10 includes a pin lip portion 11, a pin shoulder surface 12, a male screw portion 13, and a pin outer seal surface 14.
- the pin lip portion 11 constitutes the tip portion of the pin.
- the pin lip portion 11 includes an in-pin seal surface 11a, a nose portion 11b, and a base portion 11c.
- the in-pin seal surface 11 a is provided on the outer peripheral surface of the pin lip portion 11.
- the nose portion 11b is provided on the distal end side of the pin 10 with respect to the in-pin seal surface 11a. That is, the nose portion 11 b is disposed at the forefront of the pin 10.
- the base portion 11 c is a portion of the pin lip portion 11 that is closer to the male screw portion 13 than the in-pin seal surface 11 a.
- the pin shoulder surface 12 is provided at the end of the pin 10 on the steel pipe main body side.
- the pin shoulder surface 12 is an annular surface that is substantially perpendicular to the tube axis CL. More specifically, the pin shoulder surface 12 has a shape in which the outer peripheral side is slightly inclined in the screwing advance direction of the pin 10 than the inner peripheral side.
- the male screw portion 13 is provided on the outer periphery of the pin 10 between the pin lip portion 11 and the pin shoulder surface 12.
- the male screw portion 13 is composed of a single stage taper screw.
- the vertical cross-sectional shape of the screw (hereinafter simply referred to as a screw shape) is a dovetail shape.
- the pin outer seal surface 14 is provided on the outer peripheral surface of the pin 10 between the pin lip portion 11 and the pin shoulder surface 12.
- the pin outer seal surface 14 is disposed outside the male screw portion 13 in the tube axis direction.
- the box 20 includes a box inner seal surface 21, a box shoulder surface 22, a female screw portion 23, and a box outer seal surface 24.
- the box seal surface 21 is provided on the inner peripheral surface of the box 20 corresponding to the pin seal surface 11a.
- the in-box seal surface 21 contacts the in-pin seal surface 11a in the fastened state.
- the pin seal surface 11a and the box seal surface 21 have an interference amount. That is, the diameter of the pin seal surface 11 a is slightly larger than the diameter of the box seal surface 21. For this reason, the in-pin seal surface 11a and the in-box seal surface 21 come into contact with each other as the pin 10 is screwed into the box 20, and in a fastened state, the pin seal surface 11a and the in-box seal surface 21 are in close contact. Thereby, the pin inner seal surface 11a and the box inner seal surface 21 form an inner seal portion by metal contact.
- the box shoulder surface 22 corresponds to the pin shoulder surface 12 and is provided on the outer end surface of the box 22 in the tube axis direction.
- the box shoulder surface 22 is an annular surface substantially perpendicular to the tube axis CL. More specifically, the box shoulder surface 22 has a shape in which the outer peripheral side is slightly inclined in the screwing advance direction of the pin 10 than the inner peripheral side. The box shoulder surface 22 contacts the pin shoulder surface 12 in the fastened state.
- the pin shoulder surface 12 and the box shoulder surface 22 are pressed against each other by screwing the pin 10 into the box 20.
- the pin shoulder surface 12 and the box shoulder surface 22 form a shoulder portion by such mutual pressing contact.
- the pin shoulder surface 12 and the box shoulder surface 22 serve as a stopper for restricting screwing of the pin 10.
- the pin shoulder surface 12 and the box shoulder surface 22 play a role of generating a screw tightening axial force inside the joint.
- the female screw portion 23 is provided on the inner periphery of the box 20 corresponding to the male screw portion 13.
- the female screw portion 23 is configured by a one-stage taper screw that meshes with a taper screw constituting the male screw portion 13.
- the screw shape of the female screw portion 23 is a dovetail shape.
- the screw width of the screw portion constituted by the male screw portion 13 and the female screw portion 23 changes in the direction in which the pin 10 is screwed.
- the thread width of the male screw portion 13 is tapered in the direction in which the right screw advances along the string winding (lead) of the screw.
- the thread groove width of the opposed female thread portion 23 also narrows in a tapering direction in the direction in which the right screw advances along the string winding of the screw.
- the threaded portion is preferably a single thread or a double thread.
- the box outer seal surface 24 is provided on the inner peripheral surface of the box 20 corresponding to the pin outer seal surface 14.
- the box outer seal surface 24 is disposed outside the female screw portion 23 in the tube axis direction.
- the box outer seal surface 24 contacts the pin outer seal surface 14 in the fastened state.
- the pin outer seal surface 14 and the box outer seal surface 24 have an interference amount. That is, the diameter of the pin pin outer seal surface 14 is slightly larger than the diameter of the box outer seal surface 24. Therefore, the pin outer seal surface 14 and the box outer seal surface 24 come into contact with each other as the pin 10 is screwed into the box 20, and in a fastened state, the pin outer seal surface 14 and the box outer seal surface 24 are in close contact with each other. Thereby, the pin outer seal surface 14 and the box outer seal surface 24 form an outer seal portion by metal contact.
- FIG. 2 is a partially enlarged view of FIG. 1 and shows a schematic configuration of a threaded portion of the threaded joint 1.
- the male thread portion 13 has a plurality of thread crest top surfaces 13 a, thread trough bottom surfaces 13 b, insertion flank surfaces 13 c (hereinafter “insertion surfaces”) as viewed in a section cut along a plane passing through the tube axis CL. And a load flank surface 13d (hereinafter also referred to as “load surface”).
- insertion surfaces a thread crest top surfaces 13 a, thread trough bottom surfaces 13 b, insertion flank surfaces 13 c (hereinafter “insertion surfaces”) as viewed in a section cut along a plane passing through the tube axis CL.
- a load flank surface 13d hereinafter also referred to as “load surface”.
- Each insertion surface 13 c is a surface that precedes when the pin 10 is screwed into the box 20.
- Each load surface 13d is a surface opposite to the insertion surface 13d.
- the internal thread portion 23 is viewed in a cross section cut by a plane passing through the tube axis CL, and includes a plurality of thread crest top surfaces 23a, thread valley bottom surfaces 23b, insertion flank surfaces 23c (hereinafter also referred to as “insertion surfaces”), and load flank. It has a surface 23d (hereinafter also referred to as “load surface”).
- Each screw thread top surface 23 a of the female screw portion 23 faces the thread valley bottom surface 13 b of the male screw portion 13.
- Each thread valley bottom surface 23 b of the female screw portion 23 faces the screw thread top surface 13 a of the male screw portion 13.
- Each insertion surface 23 c of the female screw portion 23 faces the insertion surface 13 c of the male screw portion 13.
- Each load surface 23 d of the female screw portion 23 faces the load surface 13 d of the male screw portion 13.
- each flank angle of the insertion surfaces 13c and 23c is a negative angle of less than 0 °.
- the flank angle in the present embodiment is an angle formed by a plane perpendicular to the tube axis CL and the flank plane.
- the flank angles of the insertion surfaces 13c and 23c are positive counterclockwise. That is, each insertion surface 13c, 23c is inclined to the tip side of the pin 10 when viewed in a cross section cut by a plane passing through the tube axis CL.
- flank angles of the load surfaces 13d and 23d are also negative angles of less than 0 °. In FIG. 2, the flank angles of the load surfaces 13d and 23d are positive in the clockwise direction.
- Each load surface 13d, 23d is inclined to the opposite side to each insertion surface 13c, 23c, that is, to the steel tube main body side of the pin 10, as viewed in a cross section cut by a plane passing through the tube axis CL.
- the thread valley bottom surface 13b of the male screw portion 13 and the screw thread top surface 23a of the female screw portion 23 are in contact with each other.
- the load surfaces 13d and 23d of the male screw portion 13 and the female screw portion 23 are also in contact with each other.
- the screw thread top surface 13a of the male screw portion 13 and the screw valley bottom surface 23b of the female screw portion 23 do not contact each other.
- the insertion surfaces 13c and 23c of the male screw portion 13 and the female screw portion 23 do not contact each other.
- the insertion surface 13c of the male screw portion 13 faces the insertion surface 23c of the female screw portion 23 with a gap G therebetween.
- the gap G between the insertion surfaces 13c and 23c is an insertion surface of the female screw portion 23 opposite to the insertion surface 13c from the point where it intersects with the pitch line PL on the insertion surface 13c of the male screw portion 13 in a cross section including the pitch line PL of the screw. This is the distance in the tube axis direction up to 23c.
- the pitch line PL is a line formed by connecting points on the load surface 13d of the male screw portion 13 and at half the load surface height in the longitudinal section including the tube axis CL.
- the gap G can be appropriately determined in consideration of the degree of read error and the like. Although not particularly limited, the gap G is preferably 100 ⁇ m or less.
- the male screw portion 13 has a constant screw pitch P.
- the screw pitch P is a distance between the load surfaces 13d of adjacent screw threads. More specifically, the thread pitch P is a thread load surface 13d located next to this thread from the intersection of the thread load surface 13d and the pitch line PL in the cross section including the screw pitch line PL. And the distance in the tube axis direction to the intersection of the pitch line PL.
- the screw pitch P is the load surface pitch of the male screw portion 13.
- the thread pitch P of the male thread portion 13 is defined in this way regardless of a single thread or a multiple thread.
- FIG. 3 is a partially enlarged view of FIG. 1 and shows a schematic configuration of the inner end portion of the threaded joint 1 in the tube axis direction.
- the in-pin seal surface 11 a is a convex surface formed on the outer peripheral surface of the pin lip portion 11.
- the in-pin seal surface 11a has a shape discontinuous with the shape of the outer peripheral surface of the nose portion 11b.
- the in-pin seal surface 11a has a discontinuous shape with the shape of the outer peripheral surface of the base portion 11c. Therefore, on the outer peripheral surface of the pin lip portion 11, there are clear boundaries between the nose portion 11b and the in-pin seal surface 11a and between the in-pin seal surface 11a and the base portion 11c.
- the nose portion 11b is formed in a concave shape that is recessed toward the inner peripheral side of the pin 10 relative to the in-pin seal surface 11a.
- the base end portion 11c is formed in a concave shape that is recessed toward the inner peripheral side of the pin 10 with respect to the male screw portion 13 and the pin inner seal surface 11a.
- the outer diameter of the nose portion 11b is smaller than the diameter of the inner peripheral surface of the box 20 facing the nose portion 11b. Therefore, the nose portion 11b does not interfere with the box 20 both during and after the fastening. That is, there is always a gap between the outer peripheral surface of the nose portion 11 b and the inner peripheral surface of the box 20.
- the nose portion 11b has a cylindrical shape having a substantially constant outer diameter.
- the shape of the nose portion 11b is not particularly limited.
- the nose portion 11b may have a shape of a hollow truncated cone.
- the outer diameter of the base end portion 11c is smaller than the diameter of the inner peripheral surface of the box 20 facing the base end portion 11c. Therefore, the base end portion 11c does not interfere with the box 20 during and after the fastening, similarly to the nose portion 11b. There is always a gap between the outer peripheral surface of the base end portion 11 c and the inner peripheral surface of the box 20.
- the length in the tube axis direction of the base end portion 11c that is, the distance D in the tube axis direction between the male screw portion 13 and the pin inner seal surface 11a is determined in the tube axis direction of the nose portion 11b. It is determined in consideration of the relationship between the length L and the thread pitch P of the male thread portion 13.
- the distance D between the male screw portion 13 and the pin inner seal surface 11a indicates the length in the tube axis direction from the inner end of the male screw portion 13 to the boundary between the base portion 11c and the pin inner seal surface 11a.
- the distance D is the length in the tube axis direction of the outer peripheral surface of the pin lip portion 11 where there is substantially no step between the male screw portion 13 and the pin inner seal surface 11a.
- the length L of the nose portion 11 b indicates the length in the tube axis direction from the boundary between the pin inner seal surface 11 a and the nose portion 11 b to the tip of the pin lip portion 11.
- the length L is the length in the tube axis direction of the portion of the outer peripheral surface of the pin lip portion 11 where there is substantially no step from the inner end of the pin seal surface 11 a to the tip of the pin lip portion 11. is there.
- the distance D between the male screw portion 13 and the in-pin seal surface 11 a is 1.5 times or more the screw pitch P of the male screw portion 13.
- the length L of the nose portion 11 b is larger than the screw pitch P of the male screw portion 13.
- the difference between the distance D and the length L is within the screw pitch P. That is, the distance D between the male screw portion 13 and the pin inner seal surface 11a, the length L of the nose portion 11b, and the screw pitch P of the male screw portion 13 are determined so as to satisfy the following expressions (1) to (3).
- the distance D can be set to 3 times or less of the screw pitch P from the viewpoint of material or manufacturing cost.
- the upper limit of the distance D is not particularly specified.
- the upper limit of the length L is not particularly specified.
- FIG. 4 is a partially enlarged view of FIG. 1 and shows a schematic configuration of the inner seal portion of the threaded joint 1.
- the in-pin seal surface 11a is a convex surface including a tapered surface 111 and arcuate surfaces 112 and 113.
- the tapered surface 111 decreases in diameter toward the tip end side of the pin 10.
- the tapered surface 111 has a shape corresponding to the peripheral surface of the truncated cone having a smaller diameter on the tip side than on the steel pipe main body side.
- Arc surfaces 112 and 113 having a small curvature radius are connected to both ends of the tapered surface 111.
- the circular arc surface 112 is smoothly continuous with the inner end of the tapered surface 111 in the tube axis direction.
- the arc surface 113 is disposed on the opposite side of the arc surface 112 and smoothly continues to the outer end of the tapered surface 111 in the tube axis direction.
- Each of the arc surfaces 112 and 113 has a shape corresponding to the peripheral surface of the rotating body obtained by rotating the arc around the tube axis CL.
- the respective curvature radii of the arc surfaces 112 and 113 can be set to, for example, R3 to R30 (3 mm to 30 mm). However, the radius of curvature of each of the circular arc surfaces 112 and 113 is not limited to this. The radii of curvature of the circular arc surfaces 112 and 113 can be appropriately determined in consideration of the inclination of the tapered surface 111 and the like.
- the box seal surface 21 includes a tapered surface 211.
- the taper surface 211 is longer than the in-pin seal surface 11a.
- the tapered surface 211 extends to the outside in the tube axis direction from the in-pin seal surface 11a.
- the tapered surface 211 has an inclination corresponding to the inclination of the tapered surface 111 of the in-pin seal surface 11a.
- the distance D in the tube axis direction between the male screw portion 13 and the pin inner seal surface 11a and the length L of the nose portion 11b are determined with a balance that can effectively improve the sealing performance against the internal pressure. Yes. That is, the distance D between the male screw portion 13 and the pin inner seal surface 11a is 1.5 times or more the screw pitch P of the male screw portion 13, and the length L of the nose portion 11b is larger than the screw pitch P. Further, the difference between the distance D and the length L is within the screw pitch P.
- the pin lip portion 11 has the nose portion 11b. For this reason, the pin lip portion 11 has a large bending rigidity and is not easily deformed. Therefore, it is possible to suppress the pin lip portion 11 from bulging to the outer peripheral side due to the load of the internal pressure, and the in-pin seal surface 11a from being inclined with respect to the in-box seal surface 21. Thereby, the movement of the contact position between the pin inner seal surface 11a and the box inner seal surface 21 is suppressed, and the sealing performance against the internal pressure can be stabilized.
- the threaded joint 1 is less susceptible to various errors because a gap is formed between the insertion surface 13c of the male screw portion 13 and the insertion surface 23c of the female screw portion 23 in the fastened state. Further, since the pin shoulder surface 12 and the box shoulder surface 22 are in contact with each other in the fastening state, the completion position of the fastening can be managed. Thereby, the amount of seal interference can be stably introduced, and stable sealing performance against internal pressure and external pressure can be ensured.
- the threaded joint 1 does not require, for example, an increase in the amount of interference in the inner seal portion or a design adjustment that reduces the sealing performance of the outer seal portion.
- the adhesion of the inner seal portion can be improved. Therefore, it is possible to stably obtain an excellent sealing performance against the internal pressure while maintaining the sealing performance against the external pressure.
- the in-pin seal surface 11a is a convex surface constituted by the tapered surface 111 and the arc surfaces 112 and 113.
- the in-box seal surface 21 has a single tapered surface 211 that is longer than the in-pin seal surface 11a.
- the radius of curvature is smaller than that of a conventional seal surface in the pin which is configured as a single arc surface as a whole. Therefore, even if the in-pin seal surface 11a is inclined with respect to the in-box seal surface 21, the amount of movement of the contact position between the in-pin seal surface 11a and the in-box seal surface 21 can be reduced. As a result, the sealing performance against the internal pressure can be further stabilized.
- the pin outer seal surface 14 is arranged at the end of the pin 10 on the steel pipe main body side.
- the thread portion is disposed between the inner seal portion and the outer seal portion.
- a screw part can be constituted by a single-stage screw, and the wall thickness that can be used for the screw part can be increased compared to the case where the screw part is divided into two stages by the outer seal part. it can.
- the complete thread portion region is increased, and the decrease in the tensile strength of the screw connection can be suppressed, and the joint strength can be ensured.
- the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist thereof.
- the outer seal portion is provided outside the screw portion in the tube axis direction, but the outer seal portion may be provided at an intermediate position of the screw portion. In this case, what is necessary is just to comprise a screw part with a multistage screw.
- the threaded joint according to the above embodiment includes two seal portions (an inner seal portion and an outer seal portion). However, it can also be set as the screw joint provided with three or more seal parts.
- the seal surface in the pin is formed of a convex surface including a tapered surface and two arc surfaces.
- the shape of the seal surface in the pin is not limited to this.
- the in-pin seal surface may be a single arc surface as in the conventional case.
- the shape of the sealing surface in the box corresponding to the sealing surface in the pin is not particularly limited.
- the bottom surface of the screw thread and the top surface of the female thread portion are in contact with each other, and the top surface of the male thread portion and the bottom surface of the female thread portion are not in contact.
- the screw valley bottom surface of the male screw portion and the screw thread top surface of the female screw portion may not contact, and the screw thread top surface of the male screw portion and the screw valley bottom surface of the female screw portion may contact each other.
- Test conditions common to the control example, Examples 1-1 and 1-2, and Comparative Examples 1-1 to 1-3 are as follows.
- a pin lip portion having the shape shown in FIG. 3 having a lip thickness of 5.3 mm and a nose thickness of 4.4 mm
- Table 1 shows combinations of the distance D in the tube axis direction between the male thread portion and the seal surface in the pin and the length L in the tube axis direction of the nose portion.
- Examples 1-1 and 1-2 a combination of distance D and length L satisfying all of the following formulas (1) to (3) was applied.
- Comparative Examples 1-1 to 1-3 a combination of distance D and length L that did not satisfy at least a part of the following formulas (1) to (3) was applied.
- a screw joint having no nose was assumed, and the length L of the nose was set to zero.
- the taper surface (indicated by reference numeral TS in FIG. 5) provided in the pin lip portion is a seal surface.
- the length in the tube axis direction of the cylindrical portion located on the more distal side is the length L of the nose portion.
- the distance D between the male screw portion and the seal surface in the pin is the length in the tube axis direction of the cylindrical portion (portion where there is no step on the outer peripheral surface) between the male screw portion and the tapered surface TS.
- the screw joints according to Examples 1-1 and 1-2 clearly have a larger minimum seal surface pressure than the screw joints according to the comparative example and the comparative examples, and maintain a high seal contact force. I understand.
- the threaded joints according to Examples 1-1 and 1-2 have a smaller inclination angle of the seal surface in the pin than the threaded joints according to the comparative example and the comparative examples, so that the inclination of the seal surface in the pin is suppressed. You can see that Therefore, it can be seen that if the threaded joint satisfies the above formulas (1) to (3), the sealing performance against the internal pressure is greatly improved and stabilized.
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Abstract
Description
D≧P×1.5 (1)
L>P (2)
|D-L|≦P (3)
D≧P×1.5 (1)
L>P (2)
|D-L|≦P (3)
以下、鋼管用ねじ継手の実施形態について図面を参照しつつ説明する。図中同一及び相当する構成については同一の符号を付し、同じ説明を繰り返さない。
D≧P×1.5 (1)
L>P (2)
|D-L|≦P (3)
上記実施形態では、内圧に対する密封性能を効果的に向上させることができるバランスで、雄ねじ部13とピン内シール面11aとの管軸方向の距離D及びノーズ部11bの長さLが定められている。すなわち、雄ねじ部13とピン内シール面11aとの距離Dは、雄ねじ部13のねじピッチPの1.5倍以上であり、ノーズ部11bの長さLは、ねじピッチPよりも大きい。さらに、距離Dと長さLとの差は、ねじピッチP以内となっている。これにより、ノーズ部11bによって内シール部の密着力を増幅させつつ、距離Dに応じて得られる内圧の荷重による密着力の増幅効果がノーズ部11bによって低下するのを抑制することができる。このため、内シール部の密着力を効果的に増幅させることができる。
以上、実施形態について説明したが、本発明は上記実施形態に限定されるものではなく、その趣旨を逸脱しない限りにおいて種々の変更が可能である。例えば、上記実施形態では、管軸方向においてねじ部よりも外側に外シール部が設けられているが、ねじ部の中間位置に外シール部を設けることもできる。この場合、複数段のねじでねじ部を構成すればよい。
弾塑性有限要素解析では、対照例、実施例1-1及び1-2、並びに比較例1-1~1-3として、図1~図4に示す基本構成を有するねじ継手のモデルを使用した。対照例、実施例1-1及び1-2、並びに比較例1-1~1-3の共通の試験条件は、以下の通りである。
・鋼管の寸法:外径355.6mm、肉厚20.6mm
・材料:API規格の炭素鋼Q125(降伏応力862N/mm2)
・継手の形状:セミフラッシュ型であって、一段のねじ、外ショルダ部、及び2箇所のシール部(内外シール部)を有する、図1に示すねじ継手
・ねじの形状及び寸法:ねじ幅が変化し、断面形状がダブテイル形状の図2に示すねじであって、ねじ高さ(荷重面高さ)1.6mm、ねじピッチ(荷重面ピッチ)8.5mmのもの
・ピンリップ部の形状及び寸法:図3に示す形状のピンリップ部であって、リップ厚5.3mm、ノーズ厚4.4mmのもの
D≧P×1.5 (1)
L>P (2)
|D-L|≦P (3)
弾塑性有限要素解析では、ピンとボックスとを締結後、ISO13679のシリーズA試験を模擬した繰り返し複合荷重を負荷した。その解析過程における内シール部のシール接触力の最小値(最小シール面圧)を、対照例の値を1として相対値で比較した。また、2回目の内圧負荷時におけるピン内シール面の傾斜角を比較した。解析評価の結果を表2に示す。
Claims (8)
- 鋼管用ねじ継手であって、
管状のピンと、
鋼管本体の外径の108%よりも小さい外径を有し、前記ピンが挿入されて前記ピンと締結される管状のボックスと、
を備え、
前記ピンは、
前記ピンの先端部の外周面に設けられるピン内シール面と、前記ピン内シール面よりも前記ピンの先端側に設けられ、その外周面が、対向する前記ボックスの内周面の径よりも小さい径を有するとともに前記ピン内シール面の形状と不連続な形状を有するノーズ部と、を含むピンリップ部と、
前記ピンの鋼管本体側の端部に設けられるピンショルダ面と、
前記ピンリップ部と前記ピンショルダ面との間において前記ピンの外周に設けられ、ダブテイル形状を有するテーパねじで構成される雄ねじ部と、
前記ピンリップ部と前記ピンショルダ面との間において前記ピンの外周面に設けられるピン外シール面と、
を含み、
前記ボックスは、
前記ピン内シール面に対応して前記ボックスの内周面に設けられ、締結状態において前記ピン内シール面と接触するボックス内シール面と、
前記ピンショルダ面に対応して前記ボックスの端面に設けられ、締結状態において前記ピンショルダ面と接触するボックスショルダ面と、
前記雄ねじ部に対応して前記ボックスの内周に設けられ、ダブテイル形状を有するテーパねじで構成され、締結状態において前記雄ねじ部の挿入フランク面とすき間を空けて対向する挿入フランク面を有する雌ねじ部と、
前記ピン外シール面に対応して前記ボックスの内周面に設けられ、締結状態において前記ピン外シール面と接触するボックス外シール面と、
を含み、
前記雄ねじ部と前記ピン内シール面との管軸方向の距離をD、前記ノーズ部の管軸方向の長さをL、前記雄ねじ部のねじピッチをPとして、次の式(1)~(3)を満たす、ねじ継手。
D≧P×1.5 (1)
L>P (2)
|D-L|≦P (3) - 請求項1に記載の鋼管用ねじ継手であって、
前記ピン内シール面は、前記ピンの先端側に向かって縮径するテーパ面と、前記テーパ面の両端各々と連続する円弧面と、を含む凸状面であり、
前記ボックス内シール面は、前記ピン内シール面よりも長いテーパ面を含む、ねじ継手。 - 請求項2に記載の鋼管用ねじ継手であって、
前記円弧面の曲率半径は、3mm~30mmである、ねじ継手。 - 請求項1から3のいずれか1項に記載の鋼管用ねじ継手であって、
前記ピン外シール面は、前記ピンの鋼管本体側の端部に配置されている、ねじ継手。 - 請求項1から4のいずれか1項に記載の鋼管用ねじ継手であって、
前記距離Dは、前記ねじピッチPの3倍以下である、ねじ継手。 - 請求項1から5のいずれか1項に記載の鋼管用ねじ継手であって、
前記雄ねじ部と前記雌ねじ部とで構成されるねじ部は、リードに沿って変化するねじ幅を有する、ねじ継手。 - 請求項1から6のいずれか1項に記載の鋼管用ねじ継手であって、
前記雄ねじ部の挿入フランク面と前記雌ねじ部の挿入フランク面との間の前記すき間は、100μm以下である、ねじ継手。 - 請求項1から7のいずれか1項に記載の鋼管用ねじ継手であって、
前記雄ねじ部と前記雌ねじ部とで構成されるねじ部は、1条ねじ又は2条ねじである、ねじ継手。
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA3017114A CA3017114A1 (en) | 2016-06-08 | 2017-06-02 | Threaded connection for steel pipe |
BR112018015103-3A BR112018015103A2 (ja) | 2016-06-08 | 2017-06-02 | A screw joint for steel pipes |
MX2018011701A MX2018011701A (es) | 2016-06-08 | 2017-06-02 | Conexion roscada para tubo de acero. |
US16/083,129 US20190093799A1 (en) | 2016-06-08 | 2017-06-02 | Threaded Connection for Steel Pipe |
EP17810226.5A EP3470720B1 (en) | 2016-06-08 | 2017-06-02 | Steel pipe screw joint |
RU2018131131A RU2702315C1 (ru) | 2016-06-08 | 2017-06-02 | Резьбовое соединение для стальной трубы |
CN201780015671.7A CN108779881A (zh) | 2016-06-08 | 2017-06-02 | 钢管用螺纹接头 |
JP2018522455A JP6640347B2 (ja) | 2016-06-08 | 2017-06-02 | 鋼管用ねじ継手 |
Applications Claiming Priority (2)
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JP2016114139 | 2016-06-08 | ||
JP2016-114139 | 2016-06-08 |
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PCT/JP2017/020651 WO2017213048A1 (ja) | 2016-06-08 | 2017-06-02 | 鋼管用ねじ継手 |
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US (1) | US20190093799A1 (ja) |
EP (1) | EP3470720B1 (ja) |
JP (1) | JP6640347B2 (ja) |
CN (1) | CN108779881A (ja) |
BR (1) | BR112018015103A2 (ja) |
CA (1) | CA3017114A1 (ja) |
MX (1) | MX2018011701A (ja) |
RU (1) | RU2702315C1 (ja) |
WO (1) | WO2017213048A1 (ja) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2021044862A1 (ja) * | 2019-09-02 | 2021-03-11 | 日本製鉄株式会社 | 鋼管用ねじ継手 |
JPWO2020075366A1 (ja) * | 2018-10-11 | 2021-09-02 | 日本製鉄株式会社 | 鋼管用ねじ継手 |
WO2021261063A1 (ja) * | 2020-06-26 | 2021-12-30 | 日本製鉄株式会社 | 鋼管用ねじ継手 |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR3060701A1 (fr) | 2016-12-16 | 2018-06-22 | Vallourec Oil And Gas France | Joint filete pour composant tubulaire |
CN110651149B (zh) * | 2017-05-22 | 2021-05-07 | 日本制铁株式会社 | 钢管用螺纹接头 |
RU2747498C1 (ru) * | 2020-10-13 | 2021-05-05 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Тюменский индустриальный университет" (ТИУ) | Резьбовое замковое коническое соединение бурильных труб |
CA3202756A1 (en) * | 2020-11-23 | 2022-05-27 | United States Steel Corporation | Threaded pipe connections with improved leak tightness |
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- 2017-06-02 JP JP2018522455A patent/JP6640347B2/ja not_active Expired - Fee Related
- 2017-06-02 EP EP17810226.5A patent/EP3470720B1/en active Active
- 2017-06-02 MX MX2018011701A patent/MX2018011701A/es unknown
- 2017-06-02 CA CA3017114A patent/CA3017114A1/en not_active Abandoned
- 2017-06-02 WO PCT/JP2017/020651 patent/WO2017213048A1/ja active Application Filing
- 2017-06-02 US US16/083,129 patent/US20190093799A1/en not_active Abandoned
- 2017-06-02 CN CN201780015671.7A patent/CN108779881A/zh active Pending
- 2017-06-02 BR BR112018015103-3A patent/BR112018015103A2/ja not_active IP Right Cessation
- 2017-06-02 RU RU2018131131A patent/RU2702315C1/ru active
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EP1302623A1 (en) * | 2001-10-15 | 2003-04-16 | Hydril Company | Wedge thread with torque shoulder |
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JPWO2020075366A1 (ja) * | 2018-10-11 | 2021-09-02 | 日本製鉄株式会社 | 鋼管用ねじ継手 |
JP7237084B2 (ja) | 2018-10-11 | 2023-03-10 | 日本製鉄株式会社 | 鋼管用ねじ継手 |
WO2021044862A1 (ja) * | 2019-09-02 | 2021-03-11 | 日本製鉄株式会社 | 鋼管用ねじ継手 |
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Also Published As
Publication number | Publication date |
---|---|
CA3017114A1 (en) | 2017-12-14 |
JPWO2017213048A1 (ja) | 2018-11-01 |
CN108779881A (zh) | 2018-11-09 |
BR112018015103A2 (ja) | 2018-12-11 |
US20190093799A1 (en) | 2019-03-28 |
MX2018011701A (es) | 2019-02-18 |
EP3470720A4 (en) | 2019-05-22 |
JP6640347B2 (ja) | 2020-02-05 |
EP3470720B1 (en) | 2020-05-20 |
RU2702315C1 (ru) | 2019-10-07 |
EP3470720A1 (en) | 2019-04-17 |
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