JP2016113752A - Pipe joint fastening machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe joint fastening machine that suppresses scratching of an outer peripheral surface of a pipe body or a pipe joint and offers high fastening torque.SOLUTION: A chucking device 13 for holding a pipe joint 12 includes a plurality of holding members 21 disposed in a circumferential direction of a support unit 22, the holding members being separated from each other, and hydraulic cylinders 23 that move the respective holding members 21 independently in a radial direction. The chucking device 13 includes position detectors 28 that detect an amount of movement of each of the holding members 21, and pressure detectors that detect contacting pressure of each of the holding members 21 on the pipe joint 12. The chucking device 13 aligns all the holding members 21 evenly to a shaft center of the support unit 22, by controlling the respective hydraulic cylinders 23 on the basis of the amounts of movement detected by the position detectors 28. Then, the hydraulic cylinders 23 are actuated to move the holding members 21, and when the contact pressure detected by each of the pressure detectors reaches a prescribed contact pressure, the corresponding hydraulic cylinder 23 is stopped.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a pipe joint tightening machine in which a pipe joint is screwed into an end portion of a tubular body such as an oil well pipe.

  Oil well pipes used for oil and natural gas test and production wells have a pipe joint screwed to one end of each oil well pipe at the factory in order to facilitate connection on site. As described in Patent Document 1, a pipe joint tightening machine used for threaded mounting of a pipe joint is supported such that the inner ring is rotatable with respect to the outer ring and faces the inner peripheral side of the inner ring. A plurality of dogs each provided with a chucking claw at a tip end portion thereof are provided with chucking devices that are rotatably arranged via fulcrum pins at equal intervals in the circumferential direction with respect to the inner ring. In addition, each dog is inserted into a long hole provided at the rear end facing the outer periphery of the outer ring, and a connecting pin disposed on the outer ring is slidably inserted to rotate the outer ring and the inner ring relative to each other. The dog is configured to allow tilting around the fulcrum pin of the dog.

  In the chucking device, the pipe joint temporarily attached to the end portion of the pipe body that is held in a state where the rotation is restricted while holding the dogs at the standby position that allows the pipe joint to be inserted into the inner ring. Is inserted into the inner ring. In this state, the outer ring is driven to rotate, and at the same time, a resistance is applied to the inner ring by a brake to rotate the outer ring and the inner ring relative to each other. The claws are pressed against the outer peripheral surface of the pipe joint, and the pipe joint is gripped by a plurality of dogs. Then, the outer ring and the inner ring rotate integrally while the pipe joint is gripped by the dog, so that the pipe joint is rotated and screwed into the pipe body whose rotation is restricted. Yes.

JP 60-26796 A

  In recent years, the number of oil wells at higher depths and high load environments of high temperature, high pressure, and high corrosion has increased, so in order to improve the sealing performance at the joint between the pipe and pipe joint, High tightening torque and tightening torque accuracy are required. In order to obtain a high tightening torque of the pipe joint with respect to the pipe body, it is necessary to increase the gripping force of the pipe body and the pipe joint by the chucking device when the pipe joint is fastened to the pipe body. In the configuration in which the tube body and the pipe joint are gripped by the chucking device disclosed in Patent Document 1, the contact pressure of the chucking claw with respect to the outer peripheral surface of the tube body and the pipe joint is increased in order to increase the gripping force in the chucking device. If it is increased, the force concentrates on the contact portion of the nail, which causes a problem that surface scratches such as nail marks are easily attached. In oil well pipes used in high-load environments, cracks are likely to occur from surface flaws, so it is required to increase the tightening torque of pipe joints without causing surface flaws on the pipe body and pipe joints. The actual situation is that this type of chucking device cannot be used.

  Also, when the pipe joint is positioned in the inner ring due to bending or deformation of the pipe body or pipe joint, the axis of the pipe joint may not match the axis of the inner ring. . In the conventional chucking device, all the dogs tilt evenly due to the relative rotation of the outer ring and the inner ring. Therefore, if the axis of the pipe joint is misaligned with the axis of the inner ring, The contact pressure of each dog with the outer peripheral surface of the joint varies, and the pipe joint cannot be gripped with a uniform pressure in the circumferential direction, and the tightening torque of the pipe joint with respect to the pipe cannot be increased. Therefore, if the contact pressure of all dogs is set to be high, surface damage such as claw marks is more likely to occur due to excessively strong hitting of the dog at the part where the dog originally hits strongly, or the pipe joint itself There was a risk of deforming.

  That is, the present invention has been proposed to solve this problem in view of the above-mentioned problems inherent in the conventional technology, and it is possible to suppress damage to the outer peripheral surface of a pipe body or a pipe joint while being high. An object of the present invention is to provide a pipe joint fastening machine capable of obtaining a fastening torque.

In order to overcome the above-mentioned problems and achieve the intended object, a pipe joint fastening machine according to the invention of claim 1 is provided:
A support device (16) for holding the pipe body (11), and a screwing device (14) for screwing and mounting the pipe joint (12) to the end of the pipe body (11) held by the support device (16). In the pipe fitting tightening machine provided,
The support device (16) and the screwing device (14) include a chucking device (13, 17, 40, 46, 50) for gripping the corresponding pipe body (11) or the pipe joint (12),
The chucking device (13, 17, 40, 46, 50)
A support unit (22) through which the pipe (11) or the pipe joint (12) is inserted;
The support unit (22) is arranged at regular intervals in the circumferential direction so as to be located around the pipe body (11) or the pipe joint (12) inserted through the support unit (22) and is movable in the radial direction. Arc-shaped chuck surface (21a) that follows the outer peripheral surface of the pipe body (11) or the pipe joint (12) on the radially inner side facing the outer peripheral surface of the pipe body (11) or the pipe joint (12). A plurality of gripping members (21) formed with
First moving means (23, 41, 43, 44, 48, 51, 52, 53, 54) for moving the plurality of gripping members (21) in the radial direction;
Second moving means (23, 45, 48, 49, 56, 57) for independently moving each gripping member (21) in the radial direction;
Position detecting means (28) for detecting the amount of movement of the gripping member (21) moved by the first moving means (23, 41, 43, 44, 48, 51, 52, 53, 54);
Pressure detecting means (29) for individually detecting a contact pressure when the chuck surface (21a) of each gripping member (21) contacts the pipe body (11) or the pipe joint (12);
The first moving means (23, 41, 43, 44, 48, 51, 52, 53, 54) are controlled based on the amount of movement detected by the position detecting means (28), and each pressure detecting means ( A control device (20) for independently controlling each of the second moving means (23, 45, 48, 49, 56, 57) based on the contact pressure detected in (29),
When the contact pressure detected by each pressure detection means (29) becomes a predetermined contact pressure set in advance, the control device (20) is configured so that the second movement means (23, 45, 48, 49, 56, 57) is configured to stop control.

  According to the first aspect of the present invention, by moving the plurality of gripping members based on the amount of movement detected by the position detecting means, all the gripping members are equally spaced from the axis of the chucking device. Can do. In addition, by moving each gripping member independently and stopping each gripping member when the contact pressure of each gripping member on the pipe body or pipe joint reaches the specified contact pressure, the pipe body or pipe joint Can be held with a constant contact pressure of all the grip members. That is, by making the contact pressures of the plurality of gripping members constant, the gripping force with respect to the pipe body and the pipe joint is improved, and the pipe body and the pipe joint can be screwed and attached with a high tightening torque. Further, since the contact pressures of the plurality of gripping members can be made constant, it is not necessary to excessively increase the contact pressure in order to avoid variations in the contact pressure of the gripping members with respect to the pipe body or pipe joint. It is possible to suppress the outer peripheral surface of the joint from being damaged.

In the invention according to claim 2, the first moving means (23) and the second moving means (23) are a common hydraulic cylinder provided between the gripping members (21) and the support unit (22). The gist of the invention is that each gripping member (21) is moved in the radial direction by operating each hydraulic cylinder (23).
According to the second aspect of the present invention, both the width adjustment of the plurality of gripping members and the gripping of the pipe body and the pipe joint by each gripping member are performed by the common hydraulic cylinder, so the configuration becomes simple.

In the invention according to claim 3, the first moving means (41, 43, 44)
A wedge that is supported by the support unit (22) so as to be movable in the axial direction, and has an inclined surface (42a) that is radially displaced from one side in the axial direction toward the other side on the inner surface facing the gripping member (21). An annular member (41);
A drive means (43) disposed in the support unit (22) and reciprocally moving the wedge ring member (41) in an axial direction;
The wedge ring member (41) is supported by the support unit (22) so as to be movable in the radial direction between the inclined surface (42a) of the wedge ring member (41) and the gripping member (21), and axially driven by the drive means (43). A wedge member (44) moved in the radial direction by the wedge action of the wedge ring member (41) moved reciprocally;
The second moving means (45)
A hydraulic cylinder connected to each gripping member and a corresponding wedge member;
A hydraulic cylinder (45) connected to each gripping member (21) and a corresponding wedge member (44),
The gist of the invention is that each of the hydraulic cylinders (45) is operated independently to move the gripping member (21) toward and away from the wedge member (44) in the radial direction.
According to the third aspect of the present invention, since all the gripping members are arranged so as to be narrowed by a single wedge ring member, the control system of the first moving means can be simplified.

In the invention according to claim 4, the first moving means (41, 43, 48) is:
A wedge that is supported by the support unit (22) so as to be movable in the axial direction, and has an inclined surface (42a) that is radially displaced from one side in the axial direction toward the other side on the inner surface facing the gripping member (21). An annular member (41);
First drive means (43) disposed on the support unit (22) and reciprocally moving the wedge ring member (41) in the axial direction;
The wedge ring member (41) is supported by the support unit (22) so as to be movable in the radial direction between the inclined surface (42a) of the wedge ring member (41) and the gripping member (21), and is pivoted by the first drive means (43). A wedge member (48) moved in the radial direction by the wedge action of the wedge ring member (41) reciprocated in the direction,
The second moving means (48, 49)
A second drive means (49) disposed on each gripping member (21) and reciprocally moving the corresponding wedge member (48) in the axial direction;
Due to the wedge action of the wedge member (48) reciprocally moved in the axial direction by independently driving each of the second drive means (49), the corresponding gripping member (21) together with the wedge member (48) has a diameter. The gist is that it is configured to move in the direction.
According to the invention which concerns on Claim 4, since it comprised so that all the holding members might be brought near by the single wedge ring member, the control system of a 1st moving means can be simplified. In addition, since the gripping member is configured to move in the radial direction by the wedge action of the wedge ring member and the wedge member, the gripping state of the tube body and the pipe joint by the gripping member can be stably maintained.

In the invention according to claim 5, the first moving means (51, 52, 53, 54)
A slide ring (51) supported by the support unit (22) in an axially movable manner,
Located between the slide ring (51) and each gripping member (21) and supported by the support unit (22) so as to be movable in the radial direction in a state where movement in the axial direction is restricted, the slide ring A movable body (52) linked to (51) via a link mechanism (53);
First driving means (54) disposed on the support unit (22) and reciprocally moving the slide ring (51) in an axial direction;
The movable body (52) is moved in the radial direction by the link mechanism (53) by reciprocating the slide ring (51) in the axial direction by the first drive means (54),
The second moving means (56, 57)
A wedge member (56) supported in an axially movable manner between each movable body (52) and the corresponding gripping member (21) in the support unit (22);
Second driving means (57) disposed on each gripping member (21) and reciprocatingly moving the wedge member (56) in the axial direction;
Due to the wedge action of the wedge member (56) reciprocally moved in the axial direction by independently driving the second drive means (57), the gripping member (21) has a diameter relative to the movable body (52). The gist is that it is configured to move in a direction close to or away from the direction.
According to the invention which concerns on Claim 5, since it comprised so that a holding member might be moved to radial direction by a link mechanism (toggle mechanism), a high contact pressure can be obtained with a small stroke.

In the invention according to claim 6, the circumferential length of the chuck surface (21a) in the gripping member (21) is such that the chuck surfaces (21a) of all the gripping members (21) are connected to the pipe body (11) or the pipe joint (12). The gist of the invention is that it is set so as to be in contact with substantially the entire length of the outer peripheral surface of the pipe body (11) or the pipe joint (12) while being in contact with the outer peripheral surface.
According to the invention which concerns on Claim 6, a pipe body and a pipe joint can be stably hold | gripped by widening the contact area of the chuck surface with respect to a pipe body and a pipe joint.

In the invention according to claim 7, the chucking device (17) provided in the support device (16) rotates around an axis passing through the center of the chucking device (17) with respect to the support device (16). The gist is that displacement in a direction crossing the axis is supported in a state in which is controlled.
According to the invention of claim 7, when the pipe joint is gripped by the chucking device of the screwing device, the radial displacement of the pipe body caused by the bending of the pipe joint or the pipe body is The chucking device holding the body is allowed to be displaced with respect to the support device, and it is possible to prevent the contact pressure against the tube body and the pipe joint from being varied.

  According to the pipe joint tightening machine according to the present invention, the pipe body and the pipe joint can be screwed and attached with high tightening torque while suppressing damage to the outer peripheral surface of the pipe body and the pipe joint.

1 is a schematic configuration diagram of a pipe joint fastening machine according to Embodiment 1. FIG. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic front view of the chucking apparatus for pipe joints based on Example 1, Comprising: It has shown in the state which removed the front disk. 1 is a schematic longitudinal side view of a chucking device for a pipe joint according to Embodiment 1. FIG. It is a schematic front view which shows the support apparatus which concerns on Example 1, Comprising: It has shown in the state which removed the front disk. FIG. 3 is a control block diagram of the pipe joint tightening machine according to the first embodiment. It is a schematic front view of the chucking apparatus for pipe joints concerning Example 2, Comprising: It has shown in the state which removed the front disk. It is a schematic longitudinal side view of the chucking device for pipe joints according to the second embodiment. It is a general | schematic longitudinal cross-sectional front view of the chucking apparatus for pipe joints which concerns on Example 3. FIG. It is a schematic longitudinal side view of the chucking device for pipe joints according to the third embodiment. It is a schematic longitudinal side view of the chucking device for pipe joints according to the fourth embodiment.

  Next, a preferred embodiment of the pipe joint fastening machine according to the present invention will be described below with reference to the accompanying drawings.

  The pipe joint tightening machine 10 according to the first embodiment is installed by screwing a pipe joint 12 in which an internal thread is threaded into an end part of a tubular body 11 such as an oil well pipe in which a male thread is threaded in the outer periphery of the end part. As shown in FIG. 1, a screwing device 14 including a chucking device (first chucking device) 13 for a pipe joint that holds the pipe joint 12 is disposed on the upper surface of the bed 15. Yes. Further, a support device 16 is disposed on the upper surface of the bed 15 so as to face the disposed end portion (front end portion) of the pipe joint chucking device 13 in the screwing device 14. The support device 16 includes a tube chucking device (first chucking device) 17 that grips the tube body 11, and the tube body 11 gripped by the tube chucking device 17 is restricted from rotating. It is comprised so that it can hold | maintain in the state which was carried out. The support device 16 is disposed on the upper surface of the bed 15 so as to be movable toward and away from the screwing device 14 along the axial direction of a main shaft 19 to be described later. When the pipe joint 12 gripped by the device 13 is rotated, the support device 16 can move together with the tube body 11 that moves in the axial direction (longitudinal direction) by the screwing action of the male screw and the female screw.

  A main shaft 19 that is rotationally driven by a drive motor 18 is rotatably supported by the screwing device 14. The chucking device 13 for the pipe joint is connected to the main shaft 19 so as to rotate integrally with the main shaft 19. The drive motor 18 is electrically connected to the control device 20 (see FIG. 5), and is configured such that the drive motor 18 is driven and controlled by the control device 20.

(About chucking devices 13, 17)
Since the structure of the pipe joint chucking device 13 disposed in the screwing device 14 and the pipe chucking device 17 disposed in the support device 16 are the same, the pipe joint chucking is performed. The configuration of the device 13 will be described, and the tube chucking device 17 is denoted by the same reference numerals as those of the tube fitting chucking device 13, and detailed description thereof will be omitted. Further, hereinafter, the chucking device 13 for the pipe joint may be simply referred to as the chucking device 13.

  As shown in FIG. 2, the chucking device 13 includes a support unit 22 provided with a plurality of (six in the first embodiment) gripping members 21 that grip the pipe joint 12, and each gripping member 21 as a support unit. And moving means 23 for moving the pipe joint 12 by moving in the radial direction 22. As shown in FIG. 3, the support unit 22 is a pair of cylindrical spacers 24 and a space between the spacers 24 and spaced apart in the axial direction of the support unit 22 (a direction parallel to the axial direction of the main shaft 19). Discs 25 and 26, and one of the discs 25 is connected to the main shaft 19. Regarding the disks 25 and 26, the disk 25 connected to the main shaft 19 may be referred to as a rear disk 25 and the other disk 26 may be referred to as a front disk 26. The spacer 24 is positioned on the outer peripheral end side of both the disks 25 and 26, and the accommodating space for the gripping member 21 is defined by the both disks 25 and 26 and the spacer 24. Further, a through hole 26a through which the pipe joint 12 can be inserted and removed in the axial direction is formed in the front disk 26 in the axial center, and a pipe temporarily attached to the end of the tubular body 11 through the through hole 26a. The joint 12 is inserted into the accommodation space.

  As shown in FIG. 2, a plurality of (six in the first embodiment, six) guide members 27 between the disks 25, 26 have a regular interval along the circumferential direction. Arranged. Each guide member 27 is disposed between the disks 25 and 26 in a posture in which the apex is directed to an axis passing through the axis of the support unit 22 (also referred to as a mechanical axis), and a pair of guides adjacent to each other in the circumferential direction. The sides facing the circumferential direction of the members 27, 27 are parallel. The gripping member 21 is supported between a pair of guide members 27 adjacent to each other in the circumferential direction so as to be movable in the radial direction while the movement of the support unit 22 in the axial direction is restricted. That is, in the first embodiment, six gripping members 21 are arranged radially from the axis of the support unit 22 between the disks 25 and 26, and the six gripping members 21 are connected to the through holes 26a. It is comprised so that it may be located in the circumference | surroundings of the pipe joint 12 penetrated by the accommodation space via. Regarding the gripping member 21, an end portion facing the axial center side of the support unit 22 is referred to as an inner end portion, and an end portion facing the opposite side to the axial center side of the support unit 22 is referred to as an outer end portion. There is also.

(About the gripping member 21)
As shown in FIG. 2, an arc-shaped chuck surface 21 a that follows the outer peripheral surface of the pipe joint 12 is formed at the inner end of the gripping member 21 (inside in the radial direction facing the outer peripheral surface of the pipe joint 12). The chuck surface 21a is configured to contact the pipe joint 12 with a predetermined length in the circumferential direction without a gap. Further, in the state where the chuck surfaces 21a of the six gripping members 21 are in contact with the outer peripheral surface of the pipe joint 12, the circumference of the circle synthesized by the chuck surfaces 21a of the six gripping members 21 is It is set to be slightly larger than the circumferential length of the outer peripheral surface of the joint 12, and the pipe joint 12 can be gripped over substantially the entire circumference by the chuck surfaces 21 a of the six gripping members 21. In other words, the circumferential length of the chuck surface 21a of each gripping member 21 is adjacent to the circumferential direction when the chuck surfaces 21a of all the gripping members 21 are moved in the radial direction so as to contact the outer peripheral surface of the pipe joint 12. The dimensions are set such that the chuck surface 21a can be brought into contact with the entire circumference of the pipe joint 12 without the gripping members 21 and 21 interfering with each other.

  A hydraulic cylinder 23 as a moving means is disposed at the outer end of each gripping member 21. As shown in FIGS. 2 and 3, the hydraulic cylinder 23 includes a cylinder body 23a disposed and fixed to the gripping member 21, and a rod portion that is supported by the cylinder body 23a so as to be movable and extends from a radially outer end. Includes a piston rod 23 b that expands and contracts in the radial direction of the support unit 22, and an extended end of the piston rod 23 b is connected to the spacer 24. That is, the cylinder body 23 a and the gripping member 21 are configured to reciprocate in the radial direction with respect to the support unit 22 by extending and contracting the piston rod 23 b of the hydraulic cylinder 23. The hydraulic cylinder 23 has a cross-sectional area perpendicular to the radial direction of the support unit 22 in the connecting portion of the piston rod 23b to the spacer 24 and the holding portion of the cylinder body 23a. It is comprised larger than this, The contact reaction force which acts when holding the pipe joint 12 with the holding member 21 can be received in a wide area.

(About position detector)
As shown in FIG. 2, the support unit 22 is provided with position detectors (position detection means) 28 corresponding to the positions where the gripping members 21 are disposed. The position detector 28 is a linear gauge that detects the relative movement amount of the cylinder body 23 a and the piston rod 23 b disposed on the gripping member 21, and the movement amount detected by the position detector 28 ( Detection signal) is input to the control device 20. That is, the control device 20 is configured to be able to grasp the current position of the chuck surface 21 a in each corresponding gripping member 21 from the movement amount detected by each position detector 28. In the first embodiment, two position detectors 28 are provided for one gripping member 21, but the number of position detectors 28 may be one. In the first embodiment in which a plurality of position detectors 28 are provided for one gripping member 21, the control device 20 uses the average value of the detection values detected by the plurality of position detectors 28 as a movement amount, and the corresponding hydraulic cylinder 23. Configured to control. Further, the position detector 28 can be arbitrarily set as long as it can detect the relative movement amount of the cylinder body 23a and the piston rod 23b. In FIG. 5, only one of the two position detectors 28 included in each gripping member 21 is illustrated.

(Pressure detector)
Connected to each hydraulic cylinder 23 is a hydraulic circuit (not shown) including a hydraulic pump that supplies hydraulic oil to the hydraulic cylinder 23 and a control valve that is disposed in the hydraulic oil supply path and is controlled to open and close. The expansion and contraction operation of the piston rod 23b in the hydraulic cylinder 23 is controlled by controlling the hydraulic pump and the control valve by the control device 20. In the hydraulic circuit, a pressure detector (pressure detecting means) that detects a pressure acting on the hydraulic cylinder 23, specifically, a contact pressure acting on the gripping member 21 when the chuck surface 21a abuts on the pipe joint 12. 29 (see FIG. 5), and the contact pressure (detection signal) detected by the pressure detector 29 is input to the control device 20. The hydraulic circuit is provided independently for each hydraulic cylinder 23, and each hydraulic cylinder 23 independently moves each gripping member 21 in the radial direction by extending and contracting the piston rod 23 b independently. Configured to be able to. That is, by confirming the position and the contact pressure of each gripping member 21 with the corresponding position detector 28 and pressure detector 29, the plurality of gripping members 21 can be moved in the radial direction while adjusting the mutual position. Composed. In the first embodiment, the hydraulic cylinder 23 that moves the gripping member 21 in the radial direction is configured to serve as both the first moving unit and the second moving unit.

(About floating structure)
The support device 16 includes a support unit 22 that constitutes the tube chucking device 17 that grips the tube body 11, and the center (axial center) of the support unit 22 (chucking device 17) by a floating structure. In a state in which the rotation around the axis passing through is restricted, displacement in a direction intersecting with the axis is supported.

  As shown in FIG. 4, the outer ring body 32 is moved in the left-right direction by a pair of left and right first bearing portions 31, 31 disposed on the support base 30 of the support device 16 on a horizontal line passing through the axis of the support unit 22. Is supported so as to be rotatable about a horizontal axis in a state in which the movement is allowed. Further, the inner ring 34 is allowed to move in the vertical direction inside the outer ring 32 by a pair of upper and lower second bearing portions 33, 33 arranged on a vertical line passing through the axis of the support unit 22. The support unit 22 is supported inside the inner ring body 34 so as to be rotatable around a vertical axis. That is, the tube chucking device 17 disposed inside the inner ring body 34 is centered on the axis of the support unit 22 by the connection structure of the inner ring body 34, the outer ring body 32, and the support base 30. When the pipe joint 12 is gripped by the pipe joint chucking device 13 and supported so as to be movable in the direction intersecting the axis without rotating, the pipe joint 12 and the pipe body 11 are bent or deformed. It is configured to allow the displacement of the tube body 11 due to the above.

  Here, as shown in FIG. 4, the support unit 22 is provided with a pair of first arm portions 35, 35 protruding outward in the radial direction, spaced apart in the circumferential direction, and the inner ring 34. In addition, a pair of second arm portions 36 and 36 projecting outward in the radial direction are provided apart from each other in the circumferential direction. The second arm portion 36 corresponding to each first arm portion 35 is set so as to be spaced apart in the circumferential direction, and the first arm portion 35 and the second arm portion 36 that form a pair are a load cell or the like. They are connected via a torque detector 37. Then, screwing of the pipe joint 12 to the pipe body 11 proceeds, and the first arm portion 35 of the inner ring body 34 is connected to the torque detector 37 via the pipe chucking device 17 holding the pipe body 11. By detecting the load when the rotational force in the pressing direction is applied by the torque detector 37, the tightening torque of the pipe joint 12 with respect to the pipe body 11 can be detected. In FIG. 5, only one torque detector 37 is shown.

(About the control device 20)
In the gripping step of gripping the pipe joint 12 with the chucking device 13, the control device 20 first controls the operation of each hydraulic cylinder 23 based on the amount of movement input from the position detector 28 (specifically, the hydraulic pressure). The amount of movement of the gripping member 21 relative to the axis of the support unit 22 is monitored, and when the amount of movement reaches a preset stop movement amount, each hydraulic cylinder 23 is controlled. By controlling to stop the operation, all the gripping members 21 are configured to be able to be evenly widened with respect to the axis. In the control device 20, the state where the piston rod 23 b of the hydraulic cylinder 23 is most contracted (the holding position where the gripping member 21 is farthest from the axis of the support unit 22) is the origin, and the amount of movement from the origin is determined. The position of the chuck surface 21a from the axis of the support unit 22 can be grasped. Further, the control device 20 monitors the contact pressure of each gripping member 21 with respect to the pipe joint 12 by the contact pressure input from the corresponding pressure detector 29, and the corresponding contact pressure is a predetermined contact pressure set in advance. In this case, the corresponding hydraulic cylinders 23 are individually controlled to stop. The control device 20 is detected by the torque detector 37 when the chucking device 13 holding the pipe joint 12 is rotated by driving the drive motor 18 and the pipe joint 12 is screwed into the pipe body 11. When the tightening torque reaches a preset stop tightening torque, the drive motor 18 is controlled to stop.

[Operation of Example 1]
Next, the operation of the pipe joint tightening machine 10 of the first embodiment configured as described above will be described. As shown in FIG. 2, the grip member 21 is located at a standby position that allows the pipe joint 12 to be inserted into the through hole 26 a of the front disk 26.

  The pipe body 11 having the pipe joint 12 temporarily attached to the end is gripped by the pipe chucking device 17 of the support device 16 in a state where the pipe joint 12 protrudes to the screwing device 14 side. The gripping process of the pipe body 11 by the pipe chucking device 17 is the same as the gripping process of the pipe joint 12 by the pipe joint chucking device 13 to be described later, and a description thereof will be omitted. Then, the support device 16 is moved close to the screwing device 14 so that the pipe joint 12 is inserted into the through hole 26a of the front disk 26 in the support unit 22 of the chucking device 13 for the pipe joint. Is positioned so as to be positioned inside the gripping member group.

  As described above, the gripping process by the gripping member 21 is started in a state where the pipe joint 12 is positioned inside the gripping member group. In this gripping process, each hydraulic cylinder 23 is actuated by the control device 20 in the extending direction of the piston rod 23b. As the piston rod 23 b of each hydraulic cylinder 23 extends, the cylinder body 23 a and the gripping member 21 move toward the axis of the support unit 22. At this time, the amount of movement detected by the position detector 28 arranged corresponding to each hydraulic cylinder 23 is input to the control device 20, and the control device 20 detects the amount of movement detected by each position detector 28. By controlling the operation of each hydraulic cylinder 23 based on the above, the chuck surfaces 21a of all the gripping members 21 are brought closer to positions spaced apart by the same distance from the axis. That is, when the amount of movement detected by each position detector 28 becomes a preset amount of stop movement, the chuck surfaces 21a of all the gripping members 21 are axially centered by stopping the corresponding hydraulic cylinders 23. Are positioned at the same distance from each other. Accordingly, when the axis of the pipe joint 12 located inside the gripping member group is deviated from the axis (machine axis) of the support unit 22, the pipe joint 12 is moved by the gripping member 21 that moves by the same movement amount. The pipe joint 12 can be centered so that its axis is aligned with the machine axis.

  Next, the control device 20 operates each hydraulic cylinder 23 in the extending direction of the piston rod 23 b and moves each gripping member 21 further toward the axis of the support unit 22. When the chuck surface 21 a of each gripping member 21 comes into contact with the outer peripheral surface of the pipe joint 12, the value of the contact pressure detected by the pressure detector 29 changes, and the control device 20 determines that the detected contact pressure is When the predetermined contact pressure set in advance is reached, the operation of the corresponding hydraulic cylinder 23 is stopped. The contact pressure detected by all the pressure detectors 29 becomes the specified contact pressure, and the control device 20 stops the operation of all the hydraulic cylinders 23, whereby the gripping process of the pipe joint 12 by the gripping member 21 is completed. .

  Here, when the pipe joint 12 or the pipe body 11 is bent or deformed, when the pipe joint 12 is gripped by the pipe joint chucking device 13, the pipe body 11 in the pipe body 11 is used. The part gripped by the chucking device 17 tends to be displaced in the radial direction. When the force to which the tube body 11 restrained by the tube chucking device 17 is displaced acts on the tube joint 12, it affects the contact pressure between the tube joint 12 and the gripping member 21, and There is a possibility that the contact pressure at the gripping member 21 with respect to the pipe joint 12 may partially change. However, in the pipe joint tightening machine 10 according to the first embodiment, the support unit 22 of the tube chucking device 17 intersects the axis of the support unit 22 with respect to the support device 16 (support table 30). Therefore, the displacement of the pipe body 11 due to bending, deformation, etc. is allowed, and the contact pressure against the pipe joint 12 in the chucking device 13 for the pipe joint is prevented from changing. Thus, it is possible to maintain a state in which the pipe joint 12 is gripped with a uniform contact pressure over substantially the entire circumference.

  When the driving of the drive motor 18 is started in a state where the pipe joint 12 is gripped by the pipe joint chucking device 13, the pipe joint 12 gripped by the gripping member group by the rotation of the main shaft 19 is also obtained. The pipe joint 12 is screwed into the pipe body 11 under the screwing action of the male screw and the female screw. In this case, since the tube body 11 is held in a state in which the rotation is restricted with respect to the support device 16, the support device 16 together with the tube body 11 moves with respect to the screwing device 14 as the pipe joint 12 rotates. Move close. When the tightening torque detected by the torque detector 37 becomes a preset stop tightening torque, the control device 20 controls the drive motor 18 to stop. Thereby, the pipe joint 12 is screwed and attached to the pipe body 11 with an appropriate tightening torque.

  When the screw fitting of the pipe joint 12 to the pipe body 11 is finished, all the hydraulic cylinders 23 are operated in the contraction direction of the piston rod 23b, and the chuck surfaces 21a of all the gripping members 21 are separated from the outer peripheral surface of the pipe joint 12. By doing so, the pipe body 11 with the pipe joint 12 attached to the end can be removed from the chucking device 13 for the pipe joint.

  In the pipe joint tightening machine 10 according to the first embodiment, each of the plurality of gripping members 21 can be moved to the same separated position with respect to the axis of the support unit 22 based on the amount of movement detected by the position detector 28. The axis of the joint 12 can be aligned with the machine axis. Further, each gripping member 21 is independently moved based on the contact pressure detected by the corresponding pressure detector 29 so that the contact pressure of the pipe joint 12 by each gripping member 21 is uniform (specified contact). Since each gripping member 21 is configured to stop at a position where the pressure becomes a pressure, the pipe joint 12 can be gripped with a uniform contact pressure over substantially the entire circumference. That is, the contact pressure between the pipe joint 12 and the gripping member 21 can be prevented from partially increasing or decreasing, and the gripping force of the pipe joint 12 by the chucking device 13 can be increased. Therefore, the pipe joint 12 can be gripped with a high contact pressure without causing surface scratches such as claw marks on the outer peripheral surface of the pipe joint 12, and the pipe joint 12 can be screwed and attached to the pipe body 11 with a high tightening torque.

  In the chucking device 13, the chuck surfaces 21 a of the plurality of gripping members 21 are configured to abut over substantially the entire circumference of the pipe joint 12, so that the pipe joint 12 can be stably gripped and is high. This can contribute to screw-in mounting with tightening torque. Further, the hydraulic cylinder 23 is configured such that the cylinder body 23a is disposed on the gripping member 21 that moves in the radial direction, and the piston rod 23b is coupled to the spacer 24 of the support unit 22. The contact reaction force received by the gripping member 21 when it comes into contact with the pipe joint 12 can be received over a wide area of the cylinder body 23a. That is, even if the contact pressure of the gripping member 21 with respect to the pipe joint 12 is set high, the gripping member 21 can be stably held at a fixed position, and fluctuations in the contact pressure can be prevented.

  The tube chucking device 17 that holds the tube 11 is supported by the floating device so as to allow displacement in a direction intersecting the axis of the support unit 22 with respect to the support device 16. Therefore, it is possible to prevent the contact pressure of the gripping member 21 against the pipe joint 12 from becoming uneven due to bending or deformation of the pipe joint 12 or the pipe body 11. That is, the pipe joint 12 can be screwed and mounted with the plurality of gripping members 21 held at a uniform contact pressure, and the high-quality product can be manufactured by achieving the screwed mounting with a high tightening torque.

  Similar to the case of the pipe joint 12 gripped by the pipe joint chucking device 13, the pipe body 11 gripped by the pipe chucking device 17 extends over the entire circumference by a plurality of gripping members 21. Therefore, when the contact pressure is increased, the contact pressure is partially excessively increased, and the outer peripheral surface of the tube body 11 is prevented from being damaged. In addition, the operational effects obtained by the chucking device 17 for pipes are the same as the operational effects obtained by the chucking device 13 for pipe joints.

  6 and 7 show the second chucking device 40 according to the second embodiment, FIGS. 8 and 9 show the third chucking device 46 according to the third embodiment, and FIG. 10 shows the fourth embodiment. The 4th chucking apparatus 50 which concerns is shown. The second to fourth chucking devices 40, 46, and 50 are used for both pipe joints and pipe bodies, and will be described in the case of pipe joints. In the second to fourth chucking devices 40, 46, and 50, members having the same or the same functions as those of the chucking device 13 of the first embodiment are denoted by the same reference numerals and detailed description thereof is omitted. .

  In the second chucking device 40 according to the second embodiment shown in FIGS. 6 and 7, a cylindrical wedge ring member 41 is supported by the support unit 22 so as to be movable in the axial direction inside the spacer 24. . The wedge ring member 41 protrudes radially inward (machine axis side) at a plurality of locations spaced apart in the circumferential direction (six locations equal to the number of gripping members 21 in the second embodiment) on the inner circumferential surface. A wedge portion 42 is provided. Each wedge portion 42 is formed as an inclined surface 42 a whose inner surface (the inner surface facing the gripping member 21) is displaced in the radial direction from one side in the axial direction to the other. That is, the wedge ring member 41 is integrally formed with a wedge portion 42 (inclined surface 42a) at a position corresponding to each gripping member 21, and the plurality of wedge portions 42 (inclined surface 42a) move integrally. It is supposed to be. In the second embodiment, as shown in FIG. 7, the inclined surface 42a of the wedge portion 42 is set so as to be displaced radially outward from the front end (the support device 16 side) toward the rear side, and the wedge ring member 41 is moved to the rear side. The first wedge member 44 described later moves inward in the radial direction by moving to the side (the side away from the support device 16), and the wedge ring member 41 is moved to the front side (side adjacent to the support device 16). Thus, the first wedge member 44 is configured to move outward in the radial direction. Further, a plurality of (six in the second embodiment) first hydraulic cylinders (driving means, first driving means) 43 are disposed on the rear disk 25 of the support unit 22 so as to be separated from each other in the circumferential direction. A piston rod 43 a of one hydraulic cylinder 43 is connected to the wedge ring member 41. Then, all the first hydraulic cylinders 43 are operated in synchronism so that the piston rod 43a moves in the same direction, so that the wedge ring member 41 is axially moved in the support unit 22 by the expansion and contraction of the piston rod 43a. Configured to reciprocate.

  The plurality of first hydraulic cylinders 43 are connected to a common hydraulic circuit including a hydraulic pump and a control valve, and all the first hydraulic cylinders 43 are controlled by the control device 20 controlling the operation of one hydraulic pump. Configured to operate synchronously.

  As shown in FIG. 6, guide members 27 are arranged between a pair of wedge portions 42, 42 adjacent to each other in the circumferential direction inside the wedge ring member 41 between the disks 25, 26 in the support unit 22. It is installed. Then, as shown in FIG. 7, between the pair of guide members 27, 27 adjacent in the circumferential direction, a first wedge member (an inclined surface 44a corresponding to the inclined surface 42a of the wedge portion 42 is formed on the outer end surface ( A wedge member 44 is supported so as to be movable in the radial direction of the support unit 22. The first wedge member 44 is always urged toward the direction in which the inclined surface 44a abuts against the inclined surface 42a of the wedge portion 42 (outward in the radial direction in the second embodiment) by an urging means (not shown). Yes. That is, the first wedge member 44 is supported by the support unit 22 so as to be allowed to move in the radial direction in a state where movement in the axial direction is restricted, and the wedge ring member 41 moves in the axial direction. Thus, the first wedge member 44 is configured to move in the radial direction by the wedge action of the wedge portion 42 and the first wedge member 44.

  As shown in FIG. 6, the gripping member 21 is restricted from moving in the axial direction of the support unit 22 inside each first wedge member 44 between a pair of guide members 27, 27 adjacent in the circumferential direction. In the state, it is supported so as to be movable in the radial direction. A cylinder main body 45a of a second hydraulic cylinder (hydraulic cylinder) 45 is disposed at the outer end of each gripping member 21 having a chuck surface 21a formed at the inner end, and radially outward from the cylinder main body 45a. The extending end of the piston rod 45 b extending to the first wedge member 44 is connected to the extending end. That is, the gripping member 21 and the second hydraulic cylinder 45 that connects the gripping member 21 to the first wedge member 44 are operated when the first hydraulic cylinder 43 is operated to move the wedge ring member 41 in the axial direction. Thus, the first wedge member 44 that moves in the radial direction is integrally moved in the radial direction. The gripping member 21 can be moved toward and away from the first wedge member 44 by expanding and contracting the piston rod 45 b of the second hydraulic cylinder 45. In other words, each gripping member 21 can be independently moved in the radial direction of the support unit 22 by operating each second hydraulic cylinder 45. In the second embodiment, the wedge ring member 41, the first wedge member 44, and the first hydraulic cylinder 43 constitute first moving means for moving the plurality of gripping members 21 in the radial direction, and the second hydraulic cylinder 45. Is configured to function as second moving means for moving each gripping member 21 toward and away from the first wedge member 44. Each second hydraulic cylinder 45 is configured to be controlled independently by the control device 20.

  In the first embodiment, the position detectors 28 are provided corresponding to the respective hydraulic cylinders 23. However, in the second embodiment, all the gripping members 21 are moved in the radial direction by the movement of the single wedge ring member 41. Since it is comprised, the position detector 28 should just be provided in the position which can detect the movement amount to the radial direction of any one holding member 21. FIG. However, the pressure detectors 29 are provided corresponding to the respective second hydraulic cylinders 45 so as to be able to individually detect the contact pressure of the gripping members 21 with respect to the pipe joints 12 according to the embodiment. Same as 1. In the second embodiment, the control device 20 controls the first hydraulic cylinder 43 based on the amount of movement detected by the position detector 28, and based on the contact pressure detected by each pressure detector 29. The control device 20 is configured to individually control the corresponding second hydraulic cylinder 45.

  In the second chucking device 40 of the second embodiment, with the pipe joint 12 positioned inside the gripping member group, the plurality of first hydraulic cylinders 43 are simultaneously operated to move the wedge ring member 41 rearward in the axial direction. The first wedge member 44 and the gripping member 21 are moved radially inward by the wedge action of the wedge portion 42 and the first wedge member 44. At this time, the movement amount detected by the position detector 28 is input to the control device 20, and the control device 20 controls the operation of the first hydraulic cylinder 43 based on the movement amount detected by the position detector 28. The chuck surfaces 21a of all the gripping members 21 can be widened to positions separated by the same distance from the axis. In the second embodiment, the chuck surfaces 21a of all the gripping members 21 can be positioned at positions separated by the same distance from the shaft center only by moving the single wedge ring member 41 in the axial direction. It can be simplified. That is, since the plurality of first hydraulic cylinders 43 can be operated by being connected to a single hydraulic circuit, the control system of the first hydraulic cylinder (first moving means) 43 can be simplified.

  Next, each second hydraulic cylinder 45 is operated in the extending direction of the piston rod 45 b, and each gripping member 21 is moved toward the axis of the support unit 22. Then, the control device 20 controls the operation of each second hydraulic cylinder 45 based on the contact pressure detected by the pressure detector 29 corresponding to each gripping member 21, so that each gripping member 21 is the same as in the first embodiment. The pipe joint 12 can be gripped in a state where the contact pressure with respect to the pipe joint 12 becomes uniform.

  In the second embodiment, when all the second hydraulic cylinders 45 are operated in the contraction direction of the piston rod 45 b, the chuck surfaces 21 a of all the gripping members 21 are separated from the outer peripheral surface of the pipe joint 12. When all the first hydraulic cylinders 43 are actuated to move the wedge ring member 41 toward the front side in the axial direction, the first wedge that is biased in the direction in which the inclined surfaces come into contact with each other by the biasing member. As the member 44 moves radially outward as the wedge ring member 41 moves, the gripping member 21 returns to the standby position. By returning all the gripping members 21 to the standby position, the pipe body 11 with the pipe joint 12 attached to the end can be removed from the second chucking device 40.

  The third chucking device 46 shown in FIGS. 8 and 9 is a second moving means (second hydraulic cylinder 45) that independently moves each gripping member 21 in the second chucking device 40 in the radial direction. Since the wedge ring member 41 and the mechanism for moving the wedge ring member 41 are the same, only the different parts will be described, and the same reference numerals will be used for the same members. Detailed description will be omitted.

  A movable block 47 is integrally disposed at the rear end of each gripping member 21 so as to be movable in the radial direction. Between each wedge part 42 in the wedge ring member 41 and a movable block 47 corresponding to the wedge part 42, a second wedge member 48 is disposed so as to be movable in the axial direction. The second wedge member 48 is a member in which an inclined surface 48a corresponding to the inclined surface 42a of the corresponding wedge portion 42 is formed on the outer end surface, and is movable in the radial direction by the wedge action with the wedge portion 42. Composed. The movable block 47 is biased radially outward by a biasing means (not shown), and the second wedge member 48 biases the movable block 47 radially outward. The inclined surface 48a is always maintained in contact with the inclined surface 42a of the wedge portion 42 by the urging force.

  As shown in FIG. 9, a third hydraulic cylinder (second drive means) 49 is disposed on each movable block 47 so as to move integrally, and a piston rod 49 a of the third hydraulic cylinder 49 is provided. The second wedge member 48 is connected. Then, each third hydraulic cylinder 49 is operated to expand and contract the piston rod 49a, so that the second wedge member 48 reciprocates between the wedge portion 42 of the wedge ring member 41 and the movable block 47 in the axial direction. Configured to move. That is, the second wedge member 48 is moved in the axial direction with respect to the wedge ring member 41 located at a fixed position, so that the second wedge member 48 and the wedge portion 42 act by the wedge action. The movable block 47 and the gripping member 21 together with 48 are configured to move integrally in the radial direction. In the third embodiment, the wedge ring member 41, the second wedge member 48, and the first hydraulic cylinder (first drive means) 43 constitute first moving means for moving the plurality of gripping members 21 in the radial direction. The second wedge member 48 and the third hydraulic cylinder 49 constitute second moving means for independently moving each gripping member 21 in the radial direction. In the third embodiment, the second wedge member 48 is commonly used as a constituent member of the first moving means and the second moving means. Note that through holes 25 a that allow the third hydraulic cylinders 49 to move in the radial direction are formed in the rear disk 25 of the support unit 22 corresponding to the positions of the third hydraulic cylinders 49. .

  The third chucking device 46 according to the third embodiment is similar to the second chucking device 40 according to the second embodiment in that each of the position detector 28 that detects the amount of movement of one gripping member 21 and each third hydraulic cylinder 49 is used. Corresponding to the pressure detector 29 for detecting the contact pressure of the gripping member 21 against the pipe joint 12. In the third embodiment, the control device 20 controls the first hydraulic cylinder 43 based on the movement amount detected by the position detector 28, and based on the contact pressure detected by each pressure detector 29. The control device 20 is configured to individually control the corresponding third hydraulic cylinder 49.

  In the third embodiment, the wedge ring member 41 is moved in the axial direction to move all the gripping members 21 to a certain position with respect to the axial center, and then the third hydraulic cylinders 49 are actuated, whereby the second wedges are operated. Each gripping member 21 is brought into contact with the pipe joint 12 independently by the wedge action of the member 48 and the wedge portion 42. That is, also in the third embodiment, by moving one wedge ring member 41, all the gripping members 21 can be brought closer to a certain position with respect to the axis. In the third embodiment, the gripping member 21 is in mechanical contact with the spacer 24 of the support unit 22 via the movable block 47, the second wedge member 48, and the wedge ring member 41. The contact reaction force acting when the member 21 is contacted can be stably received. In other words, since the fluid (oil or air) whose volume is changed by pressure is not interposed between the gripping member 21 and the spacer 24, the position of the gripping member 21 is prevented from being displaced by the contact reaction force. The state in which the pipe joint 12 is stably held with a high contact pressure can be maintained.

  In the fourth chucking device 50 according to the fourth embodiment shown in FIG. 10, a cylindrical slide ring 51 is supported on the support unit 22 so as to be movable in the axial direction inside the spacer 24. In addition, a plurality of guide members 27 are disposed in the support unit 22 inside the slide ring 51 so as to be spaced apart from each other in the circumferential direction, and the movable body 52 is disposed between a pair of guide members 27, 27 adjacent in the circumferential direction. It is supported so as to be movable in the radial direction. In the fourth embodiment, six movable bodies 52 are spaced apart in the circumferential direction. Each movable body 52 is connected to the slide ring 51 via a link mechanism 53 including a plurality of link rods. In the fourth embodiment, a parallel link mechanism is used as the link mechanism 53.

  A plurality of (six in the fourth embodiment) fourth hydraulic cylinders (first drive means) 54 are disposed on the rear disk 25 of the support unit 22 so as to be spaced apart from each other in the circumferential direction. The piston rod 54 a is connected to the slide ring 51. The slide ring 51 is configured to reciprocate in the axial direction within the support unit 22 by operating all the fourth hydraulic cylinders 54 to expand and contract the piston rods 54a. In the fourth embodiment, the movement of the movable body 52 in the axial direction is restricted by the front and rear disks 25 and 26, and the movable body 52 is moved in the radial direction via the link mechanism 53 when the slide ring 51 moves in the axial direction. It is supposed to move only to. That is, in the fourth embodiment, a toggle mechanism is constituted by the slide ring 51, the link mechanism 53 and the movable body 52, and the pivot point for the slide ring 51 and the pivot point for the movable body 52 in the link rod constituting the link mechanism 53. Are set so that the maximum force is expressed at a position where the two are aligned in the radial direction (hereinafter referred to as an operating position of the slide ring 51). The front disk 26 of the support unit 22 is provided with a stopper 55 at a position facing the slide ring 51 in the axial direction. The slide ring 51 is positioned at the operating position with the front end abutting against the stopper 55. It has become. The plurality of fourth hydraulic cylinders 54 are connected to a common hydraulic circuit, and are configured such that all the fourth hydraulic cylinders 54 are simultaneously controlled by the control device 20.

  Inside each movable body 52, a third wedge member (wedge member) 56 is supported so as to be movable in the axial direction between a pair of guide members 27, 27 adjacent in the circumferential direction. As shown in FIG. 10, the third wedge member 56 is formed as an inclined surface 56 a whose inner surface is displaced in the radial direction from one end side in the axial direction toward the other end side. Further, inside each third wedge member 56, the gripping member 21 is restricted from moving in the axial direction of the support unit 22 between the pair of guide members 27, 27 adjacent in the circumferential direction. It is supported so as to be movable in the radial direction. An inclined surface 21 b corresponding to the inclined surface 56 a is formed on the outer end surface of the gripping member 21 facing the inclined surface 56 a of the third wedge member 56. The gripping member 21 is movable toward and away from the movable body 52 in the radial direction, and is always urged toward the direction close to the movable body 52 (outside in the radial direction) by an urging means (not shown). Yes. The third wedge member 56 is sandwiched between the gripping member 21 and the movable body 52 by the biasing force of the biasing means, and the inclined surface 56a of the third wedge member 56 and the tilted surface 21b of the gripping member 21 are Is always kept in contact with the urging force of the urging means.

  A fifth hydraulic cylinder (second drive means) 57 is disposed on each movable body 52 so as to be integrally movable, and a piston rod 57a of the fifth hydraulic cylinder 57 is a third wedge member 56. It is connected to. The third wedge member 56 is configured to reciprocate between the movable body 52 and the gripping member 21 in the axial direction by operating each fifth hydraulic cylinder 57 to expand and contract the piston rod 57a. The That is, by moving the third wedge member 56 in the axial direction relative to the gripping member 21 whose movement in the axial direction is restricted, the gripping member 21 is caused by the wedge action of the third wedge member 56 and the gripping member 21. Is configured to move radially. The fifth hydraulic cylinder 57 is inserted into a through hole 25a formed in the rear disk 25 so as to be allowed to move in the radial direction. In the fourth embodiment, the slide ring 51, the link mechanism 53, the movable body 52, and the fourth hydraulic cylinder (first driving means) 54 constitute first moving means for moving the plurality of gripping members 21 in the radial direction. The third wedge member 56 and the fifth hydraulic cylinder (second drive means) 57 constitute second moving means for independently moving the gripping members 21 in the radial direction.

  Similar to the chucking devices 40 and 46 of the second and third embodiments, the fourth chucking device 50 of the fourth embodiment includes a position detector 28 that detects the amount of movement of one gripping member 21, and each fifth hydraulic cylinder 57. The pressure detector 29 which detects the contact pressure with respect to the pipe joint 12 of the holding member 21 corresponding to each of these is provided. In the fourth embodiment, the control device 20 controls the fourth hydraulic cylinder 54 based on the movement amount detected by the position detector 28, and based on the contact pressure detected by each pressure detector 29. The control device 20 is configured to individually control the corresponding fifth hydraulic cylinder 57.

  In the fourth chucking device 50 according to the fourth embodiment, the plurality of fourth hydraulic cylinders 54 are simultaneously operated to move the slide ring 51 in the axial direction while the pipe joint 12 is positioned inside the gripping member group. Thus, the movable body 52 moves radially inward by the link mechanism 53. Since the gripping member 21 is configured to be movable integrally in the radial direction with the third wedge member 56 sandwiched between the movable body 52 and the gripping member 21 and the third wedge member 56, It moves radially inward integrally with the movable body 52. At this time, the movement amount detected by the position detector 28 is input to the control device 20, and the control device 20 controls the operation of the fourth hydraulic cylinder 54 based on the movement amount detected by the position detector 28. The chuck surfaces 21a of all the gripping members 21 can be widened to positions separated by the same distance from the axis. In the fourth embodiment, the stop position of the gripping member 21 that is moved based on the amount of movement detected by the position detector 28 is set to the width adjustment position before the slide ring 51 reaches the operating position. . In the fourth embodiment, similarly to the second and third embodiments, the chuck surfaces 21a of all the gripping members 21 are positioned at positions separated by the same distance from the shaft center only by moving the slide ring 51 in the axial direction. Thus, the configuration can be simplified. That is, since the plurality of fourth hydraulic cylinders 54 can be operated by connecting them to a single hydraulic circuit, the control system of the fourth hydraulic cylinder (first moving means) 54 can be simplified.

  Next, each fifth hydraulic cylinder 57 is operated, and the third wedge member 56 and the gripping member are moved in the axial direction with respect to the movable body 52 located at a fixed position. The wedge member 21 moves the grip member 21 radially inward, and the chuck surface 21 a comes into contact with the outer peripheral surface of the pipe joint 12. Then, the control device 20 controls the operation of each fifth hydraulic cylinder 57 based on the contact pressure detected by the pressure detector 29 corresponding to each gripping member 21, so that each gripping member 21 is the same as in the first embodiment. The pipe joint 12 can be gripped in a state where the contact pressure with respect to the pipe joint 12 becomes uniform. In the fourth embodiment, the fourth hydraulic cylinder 54 is further operated, and the gripping member 21 is further moved radially inward via the movable body 52 and the third wedge member 56 by the link mechanism 53, and the slide The control device 20 stops the fourth hydraulic cylinder 54 at a position where the ring 51 contacts the stopper 55. Thereby, all the holding members 21 can be held at a position where the maximum force is expressed by the toggle mechanism, and the pipe joint 12 can be held with a high contact force.

  In the fourth embodiment, since the gripping member 21 is moved by using the toggle machine, the contact pressure of the pipe joint 12 by the gripping member 21 is increased while keeping the stroke for moving the slide ring 51 small. This can contribute to the screw-in mounting of the pipe joint 12 and the pipe body 11 with a high tightening torque. Moreover, since the moving stroke of the slide ring 51 can be reduced, the apparatus can be reduced in size. Further, in the fourth embodiment, the gripping member 21 is mechanically in contact with the spacer 24 of the support unit 22 via the third wedge member 56, the movable body 52, the link mechanism 53, and the slide ring 51. The state in which the joint 12 is stably gripped with a high contact pressure can be maintained.

[Example of change]
This application is not limited to the structure of Examples 1-4 mentioned above, The other structure can be employ | adopted suitably.
(1) In Embodiments 1 to 4, six holding members are disposed in the support unit. However, the number of the holding members is not limited to six, and a cylindrical pipe joint or tube body can be stably provided. As long as it is a number that can be gripped, it may be at least three.
(2) In Embodiments 2 to 4, the wedge ring member or the slide ring is configured to move in the axial direction by using six (plural) hydraulic cylinders. However, the hydraulic cylinder that moves the wedge ring member or the slide ring is 1 Or a plurality other than six.
(3) In the second to fourth embodiments, the wedge ring member or the slide ring is configured to move in the axial direction by the hydraulic cylinder. The means for moving the wedge ring member or the slide ring is linked to a rotary actuator such as a motor. Various other known mechanisms such as a combination of mechanisms and a combination of a rotary actuator and a ball screw can be employed.
(4) In the third to fourth embodiments, the second wedge member or the third wedge member is configured to move in the axial direction by the hydraulic cylinder. However, the means for moving each wedge member includes a rotary actuator such as a motor and the like. Various other known mechanisms such as a mechanism combining a link mechanism and a mechanism combining a rotary actuator and a ball screw can be adopted.
(5) In the first embodiment, the hydraulic cylinder provided between each gripping member and the support unit is configured such that the cylinder body is disposed on the gripping member and the piston rod is connected to the support unit (spacer). A configuration may be employed in which the cylinder body is disposed in the support unit (spacer) and the piston rod is connected to the gripping member.

(6) In the first embodiment, the hydraulic cylinder is controlled based on the amount of movement detected by the position detector, the gripping member is brought closer to the shaft center of the support unit, and then the hydraulic cylinder is temporarily stopped, and then the pressure The hydraulic cylinder is controlled based on the contact pressure detected by the detector and the fitting is gripped by the gripping member. However, the hydraulic cylinder is continuously shifted and gripped without temporarily stopping. A configuration may be employed.
(7) In the fourth embodiment, a position sensor 58 (see FIG. 10) for detecting the slide ring 51 before the slide ring 51 reaches the operating position is disposed on the support unit 22, and the plurality of gripping members 21 are arranged on the support unit. In the step of narrowing to the shaft center of 22, it is possible to adopt a configuration in which the control device 20 stops and controls the fourth hydraulic cylinder 54 by a detection signal from the position sensor 58. Then, after each gripping member 21 is moved by the fifth hydraulic cylinder 57 until the individual contact pressure becomes uniform, the fourth hydraulic cylinder 54 is actuated again to move the slide ring 51 to the operating position. You may make it do.
(8) Instead of the second moving means of the gripping member by the third wedge member and the fifth hydraulic cylinder employed in the fourth embodiment, the second moving means of the gripping member by the second hydraulic cylinder employed in the second embodiment. Can be used. In other words, a hydraulic cylinder can be disposed between the movable body and the gripping member, and the gripping member can be moved toward and away from the movable body by the operation of the hydraulic cylinder. In this case, the cylinder body of the hydraulic cylinder may be arranged on either side of the gripping member and the movable body.
(9) A hydraulic cylinder can be used in place of the first moving means of the gripping member by the toggle mechanism employed in the fourth embodiment. In other words, a hydraulic cylinder may be disposed between the support unit (spacer) and the movable body, and the movable body may be moved toward and away from the support unit (spacer) by the operation of the hydraulic cylinder. In this case, the cylinder body of the hydraulic cylinder may be arranged on either side of the support unit (spacer) and the movable body.
(10) A chucking device configured to be able to independently adjust the width of each gripping member with a hydraulic cylinder as in the first embodiment is provided with a measuring means for measuring the outer diameter of a pipe joint or a pipe body, After each gripping member is narrowed by a hydraulic cylinder to a position corresponding to the outer diameter of the pipe joint or tube measured by the measuring means, each gripping member is hydraulically operated based on the contact pressure detected by the pressure detector. It is possible to adopt a configuration in which a pipe joint or a pipe body to be gripped is gripped with an appropriate contact pressure by moving independently with a cylinder. In addition, you may make it input the outer diameter of a pipe joint and a pipe body to be grasped beforehand to a control device about the outer diameter of a pipe joint or a pipe body.
(11) In the chucking device configured so that each of the gripping members can be independently shifted by a hydraulic cylinder as in the first embodiment, the pipe joint and the pipe according to the outer diameter of the pipe joint and the pipe body. You may make it vary the number of the holding members which hold | grip a body. That is, based on the outer diameter information of the pipe joint and the pipe body measured by the measuring means and the outer diameter information of the pipe joint and the pipe body previously input to the control device, the number of gripping members corresponding to the outer diameter It is possible to adopt a configuration in which the width is selected and the width is adjusted and held.
(12) In the chucking device configured to be able to independently adjust the width of each gripping member as in the first embodiment, a part of the gripping members is not provided for all the gripping members. It is possible to adopt a configuration in which a pipe joint and a pipe body are centered using a gripping member provided only for the position detector and provided with a position detector, and thereafter, all the gripping members are used to grip the pipe joint and the pipe body. . As described above, according to the configuration in which the pipe joint and the pipe body are centered using a part of the gripping members, it is not necessary to perform position control by the position detector for all the gripping members. Can be reduced.

DESCRIPTION OF SYMBOLS 11 Tubing body 12 Pipe joint 13 Chucking device for pipe joints 14 Screwing device 16 Supporting device 17 Chucking device for tubular body 20 Control device 21 Holding member 21a Chuck surface 22 Supporting unit 23 Hydraulic cylinder (first moving means, first moving means (2 moving means)
28 Position detector (position detection means)
29 Pressure detector (pressure detection means)
40 Second chucking device (chucking device)
41 Wedge ring member (first moving means)
42a inclined surface 43 first hydraulic cylinder (driving means, first driving means, first moving means)
44 First wedge member (wedge member, first moving means)
45 Second hydraulic cylinder (hydraulic cylinder, second moving means)
46 Third chucking device (chucking device)
48 Second wedge member (wedge member, first moving means, second moving means)
49 3rd hydraulic cylinder (2nd drive means, 2nd moving means)
50 4th chucking device (chucking device)
51 Slide ring (first moving means)
52 Movable body (first moving means)
53 Link mechanism (first moving means)
54 Fourth hydraulic cylinder (first driving means, first moving means)
56 Third wedge member (wedge member, second moving means)
57 Fifth hydraulic cylinder (second driving means, second moving means)

Claims (7)

In a pipe joint fastening machine comprising: a support device for holding a pipe body; and a screwing device for screwing and fitting a pipe joint to an end of the pipe body held by the support device.
The support device and the screwing device include a chucking device that grips a corresponding pipe body or pipe joint,
The chucking device is
A support unit through which the pipe body or pipe joint is inserted;
An outer periphery of the pipe body or the pipe joint is arranged at a constant interval in the circumferential direction so as to be located around the pipe body or the pipe joint inserted through the support unit, and is movably supported in the radial direction. A plurality of gripping members in which arc-shaped chuck surfaces that follow the outer peripheral surface of the pipe body or pipe joint are formed on the inner side in the radial direction facing the surface;
First moving means for moving the plurality of gripping members in a radial direction;
A second moving means for independently moving each gripping member in the radial direction;
Position detecting means for detecting the amount of movement of the gripping member moved by the first moving means;
Pressure detecting means for individually detecting a contact pressure when the chuck surface of each gripping member is in contact with the pipe body or the pipe joint;
Control that controls the first moving means based on the amount of movement detected by the position detecting means, and that independently controls the second moving means based on the contact pressure detected by each pressure detecting means. With the device,
The control device is configured to stop and control each of the second moving means when the contact pressure detected by each pressure detecting means reaches a preset specified contact pressure. Pipe fitting tightening machine.   The first moving means and the second moving means are constituted by a common hydraulic cylinder provided between each gripping member and the support unit, and each gripping member is moved in the radial direction by operating each hydraulic cylinder. The pipe joint fastening machine according to claim 1, wherein the pipe joint fastening machine is configured to perform. The first moving means includes
A wedge ring member that is supported by the support unit so as to be movable in the axial direction, and an inner surface facing the gripping member is formed with an inclined surface that is displaced in the radial direction from one side to the other in the axial direction;
A driving means disposed in the support unit and configured to reciprocate the wedge ring member in the axial direction;
The wedge unit is supported by the support unit so as to be movable in the radial direction between the inclined surface of the wedge ring member and each gripping member, and is moved in the radial direction by the wedge action of the wedge ring member that is reciprocated in the axial direction by the driving means. A wedge member to be moved,
The second moving means includes
A hydraulic cylinder connected to each gripping member and a corresponding wedge member;
The pipe joint tightening machine according to claim 1, wherein each of the hydraulic cylinders is operated independently to move the gripping member toward and away from the wedge member in the radial direction. The first moving means includes
A wedge ring member that is supported by the support unit so as to be movable in the axial direction, and an inner surface facing the gripping member is formed with an inclined surface that is displaced in the radial direction from one side to the other in the axial direction;
A first drive means disposed in the support unit and reciprocally moving the wedge ring member in the axial direction;
The wedge ring member is supported by the support unit so as to be movable in the radial direction between the inclined surface of the wedge ring member and each gripping member, and the wedge ring member is reciprocated in the axial direction by the wedge action of the wedge ring member. A wedge member moved in the direction,
The second moving means includes
A second driving means disposed on each gripping member and reciprocally moving the corresponding wedge member in the axial direction;
2. A structure in which a corresponding gripping member is moved together with the wedge member in a radial direction by a wedge action of a wedge member reciprocally moved in the axial direction by independently driving each of the second driving means. Pipe fitting tightening machine. The first moving means includes
A slide ring supported by the support unit so as to be movable in the axial direction;
Located between the slide ring and each gripping member, supported by the support unit so as to be movable in the radial direction in a state where movement in the axial direction is restricted, and linked to the slide ring via a link mechanism A movable body,
A first drive means disposed on the support unit and configured to reciprocate the slide ring in the axial direction;
By reciprocating the slide ring in the axial direction by the first driving means, the movable body is configured to move in the radial direction by a link mechanism,
The second moving means includes
A wedge member supported so as to be movable in the axial direction between each movable body and the corresponding gripping member in the support unit;
A second drive means disposed on each gripping member and reciprocally moving the wedge member in the axial direction;
The gripping member is configured to be moved toward and away from the movable body in the radial direction by a wedge action of a wedge member that is reciprocally moved in the axial direction by independently driving the second driving means. Item 1. The pipe joint fastening machine according to Item 1.   The circumferential length of the chuck surface of the gripping member is approximately the entire length of the outer peripheral surface of the tube or pipe joint in a state where the chuck surfaces of all the gripping members are in contact with the outer peripheral surface of the pipe or pipe joint. The pipe joint fastening machine according to any one of claims 1 to 5, wherein the pipe joint fastening machine is set to contact.   The chucking device provided in the support device supports the support device so that the support device can be displaced in a direction intersecting the axis line while the rotation around the axis line passing through the center of the chucking device is restricted with respect to the support device. The pipe joint fastening machine according to any one of claims 1 to 6.

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