Multi-stage combined slip

Abstract

A multi-stage combined slip relates to the technical field of drilling equipment, the rear surface of each single slip is a rear arc surface, the front surface of each single slip is a front arc surface, the rear arc surfaces are in clearance fit with arc grooves, the front arc surfaces are the same as the outer circle of a clamped drill rod in size, and a row of single slips are mounted in the arc grooves of a retainer from bottom to top. The upper portion of the uppermost single slip of the retainer is connected with a U-shaped lock, the retainer is provided with a supporting seat at the bottom of the arc groove, and the supporting seat blocks the lower portions of the single slips. The single slip has the beneficial effects that when the front arc surface of the single slip clamps the drill rod, the front arc surface is elastically deformed by pressure, and the elastically deformed single slip can be completely attached to the drill rod to adapt to roundness deformation generated in the manufacturing and using process of the drill rod; the single slips arranged up and down can adapt to straightness deformation generated in the manufacturing and using process of the drill rod, the technical scheme of the invention considers the deformation problem of the drill rod, and the clamping strength can be greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of drilling equipment, and in particular to a multi-stage combined slip. Background Art

[0002] The power tongs are the key components of the main machine of the continuous circulation drilling device. They are mainly composed of four parts: the base assembly, the clamping mechanism, the screw-on mechanism and the make-up and make-off mechanism. Among them, the slips are components of the clamping mechanism. They are used to clamp the drill pipe when connecting and disconnecting the drill pipe (single or column) in continuous circulation drilling. The screw-on mechanism is then used to drive the drill pipe to rotate the screw-on, and the make-up and make-off mechanism is used to perform the make-up and make-off operation, ensuring that the slips clamp the drill pipe and the clamping is more uniform and reliable. The current power tongs slips have realized the need to clamp the drill pipe in structure, but there is no further improvement at the micro level. For example, the roundness and straightness of the drill pipe at the micro level cannot be used (that is, the rigid clamping of the slips to the drill pipe) reduces the clamping firmness of the slips. Summary of the invention

[0003] In order to solve the problem that the current power tongs have low clamping firmness, the present invention provides a multi-stage combined slip.

[0004] The technical solution provided by the present invention is: a multi-stage combined slip, comprising a retainer, a single slip and a U-shaped lock, wherein an arc groove in the up-down direction is provided in the front of the retainer, an ear plate is provided in the rear of the retainer, the single slip is a disc-shaped structure, the rear of the single slip is a rear arc surface, the front of the single slip is a front arc surface, the centers of the rear arc surface and the front arc surface are in a straight line, the rear arc surface and the arc groove are gap-matched, the front arc surface has the same size as the outer circle of the drill pipe being clamped, a row of single slips are installed from bottom to top in the arc groove of the retainer, the upper part of the uppermost single slip of the retainer is connected to the U-shaped lock, the retainer is provided with a support seat at the bottom of the arc groove, and the support seat blocks the lower part of the single slip; The wrap angle of the arc groove is greater than 180°, the arc groove is provided with a limit groove in the up-down direction at the symmetrical point of the arc, the single slip extends a limit strip in the up-down direction outward at the symmetrical point of the rear arc surface, the limit strip is located in the limit groove, the width of the limit groove is greater than the width of the limit strip, the two side wall arms of the U-shaped lock each extend inward with a side falcon strip, the horizontal arm of the U-shaped lock extends inward with a horizontal falcon strip, the two side surfaces of the retainer are provided with side slots, the front of the retainer is provided with a horizontal slot, the horizontal falcon strip of the U-shaped lock is inserted into the horizontal slot of the retainer, and the side falcon strip is inserted into the side slot of the retainer; A closed cavity is provided in the single slip, and the cavity is developed around the inner side of the front arc.

[0005] The single slip has cutting seams that run through from top to bottom on the front arc surface. The cutting seams are evenly arranged on the front arc surface. The depth of the cutting seams is 3mm and the width of the cutting seams is 0.2mm.

[0006] The cavity is filled with hydraulic oil.

[0007] The inner end surface of the side falcon bar is inlaid with a permanent magnet block.

[0008] The beneficial effects of the present invention are as follows: the single slip is connected through the clearance fit of the rear arc surface and the arc groove of the retaining frame, and the single slip can rotate limitedly in the arc groove so that the front arc surface of the single slip is directly opposite to the outer circle of the drill pipe, thereby avoiding the problem of the slip being misaligned due to the manufacturing error of the power tongs themselves during hard connection; when the front arc surface of the single slip clamps the drill pipe, the pressure causes the front arc surface to produce elastic deformation, and the elastically deformed single slip can be completely attached to the drill pipe to adapt to the roundness deformation of the drill pipe itself during the manufacturing and use processes; the single slips arranged up and down can adapt to the straightness deformation of the drill pipe during the manufacturing and use processes. The technical solution of the present invention takes into account the deformation problem of the drill pipe and can greatly improve the clamping strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Attached Figure 1 It is a schematic diagram of the structure of the present invention; Attached Figure 2 It is a schematic diagram of the structure of the retainer in the present invention; Attached Figure 3 It is a schematic diagram of the structure of a single slip in the present invention; Attached Figure 4 is a cross-sectional view of a single slip in the present invention; Attached Figure 5 It is a structural schematic diagram of the U-shaped lock in the present invention.

[0010] In the figure, 1-retaining frame, 101-arc groove, 102-ear plate, 103-support seat, 104-limiting groove, 105-side clamping groove, 106-horizontal clamping groove, 2-single slip, 201-rear arc surface, 202-front arc surface, 203-limiting strip, 204-cutting seam, 205-cavity, 3-U-shaped lock, 301-side falcon bar, 302-horizontal falcon bar, 303-permanent magnet block. DETAILED DESCRIPTION

[0011] like Figures 1 to 5 As shown, a multi-stage combined slip comprises a retainer 1, a single slip 2 and a U-shaped lock 3. An arc groove 101 in the up-down direction is provided at the front of the retainer 1, and an ear plate 102 is provided at the rear of the retainer 1 for connecting a power tong. The single slip 2 is a disc-shaped structure. The rear of the single slip 2 is a rear arc surface 201, and the front is a front arc surface 202. The centers of the rear arc surface 201 and the front arc surface 202 are in a straight line. The rear arc surface 201 and the arc groove 101 are clearance-matched. The front arc surface 202 has the same size as the outer circle of the drill pipe being clamped. A row of single slips 2 are installed from bottom to top in the arc groove 101 of the retainer 1. The retainer 1 is connected to the U-shaped lock 3 at the upper part of the uppermost single slip 2. The retainer 1 is provided with a support seat 103 at the bottom of the arc groove 101, and the support seat 103 blocks the lower part of the single slip 2. The wrap angle of the arc groove 101 is greater than 180°, and the arc groove 101 is provided with a limit groove 104 in the up-down direction at the symmetrical point of the arc. The single slip 2 extends a limit strip 203 in the up-down direction outward at the symmetrical point of the rear arc surface 201, and the limit strip 203 is located in the limit groove 104. The width of the limit groove 104 is greater than the width of the limit strip 203. The two side wall arms of the U-shaped lock 3 each extend inward with a side falcon strip 301, and the horizontal arm of the U-shaped lock 3 extends inward with a horizontal falcon strip 302. The two side surfaces of the retainer 1 are provided with side slots 105, and the front of the retainer 1 is provided with a horizontal slot 106. The horizontal falcon strip 302 of the U-shaped lock 3 is inserted into the horizontal slot 106 of the retainer 1, and the side falcon strip 301 is inserted into the side slot 105 of the retainer 1. A sealed cavity 205 is provided in the single slip 2, and the cavity 205 is extended around the inner side of the front arc 202. The arrangement of the cavity 205 enables the front arc surface 202 of the single slip 2 to produce elastic deformation when under pressure.

[0012] The single cava 2 is connected with the arc groove 101 of the retaining frame 1 through a clearance fit of the rear arc surface 201. The single cava 2 can rotate limitedly in the arc groove 101, so that the front arc surface 202 of the single cava 2 is opposite to the outer circle of the drill pipe, avoiding the problem of the cava being misaligned due to the manufacturing error of the power tongs itself during hard connection. When the front arc surface 202 of the single cava 2 clamps the drill pipe, the pressure causes the front arc surface 202 to produce elastic deformation. The elastically deformed single cava 2 can be completely attached to the drill pipe to adapt to the roundness deformation of the drill pipe itself during the manufacturing and use processes. The single cava 2 arranged up and down can adapt to the straightness deformation of the drill pipe during the manufacturing and use processes. The technical solution of the present invention takes into account the deformation problem of the drill pipe and can greatly improve the clamping strength.

[0013] The single slip 2 has cutting slits 204 that penetrate up and down on the front arc surface 202. The cutting slits 204 are evenly arranged on the front arc surface 202. The depth of the cutting slits 204 is 3 mm, and the width of the cutting slits 204 is 0.2 mm. The cutting slits 204 allow the front arc surface 202 to have space for elastic deformation.

[0014] The cavity 205 is filled with hydraulic oil. Due to the incompressibility of the hydraulic oil, a part of the current arc surface 202 is elastically deformed too much inward, and the hydraulic oil flows to the part of the front arc surface 202 where there is no deformation, that is, the single slip 2 wraps the drill pipe without dead angle.

[0015] The U-shaped lock 3 inserted from one side of the drill rod will not be loosened during operation. The inner end surface of the side falcon bar 301 is inlaid with a permanent magnet block 303, which magnetically attracts the side slot 105 to keep it in position. When disassembling, the U-shaped lock 3 can be unlocked by knocking from the outside.

Claims

1. A multi-stage combined slip, comprising a retainer (1), a single slip (2) and a U-shaped lock (3), characterized in that: The front of the retainer (1) is provided with an arc groove (101) in the up-down direction, the rear of the retainer (1) is provided with an ear plate (102), the single slip (2) is a disc-shaped structure, the rear of the single slip (2) is a rear arc surface (201), and the front is a front arc surface (202), the centers of the rear arc surface (201) and the front arc surface (202) are on a straight line, the rear arc surface (201) and the arc groove (101) are clearance-matched, the front arc surface (202) and the outer circle size of the drill pipe being clamped are the same, a row of single slips (2) are installed from bottom to top in the arc groove (101) of the retainer (1), the retainer (1) is connected to the upper part of the uppermost single slip (2), the retainer (1) is provided with a support seat (103) at the bottom of the arc groove (101), and the support seat (103) blocks the lower part of the single slip (2); The arc groove (101) has a wrap angle greater than 180°, the arc groove (101) is provided with a limit groove (104) in the up-down direction at a symmetrical point of the arc, the single slip (2) extends a limit strip (203) in the up-down direction outward at a symmetrical point of the rear arc surface (201), the limit strip (203) is located in the limit groove (104), the width of the limit groove (104) is greater than the width of the limit strip (203), and the two ends of the U-shaped lock (3) are The side wall arms each extend inwardly with a side falcon bar (301), the horizontal arm of the U-shaped lock (3) extends inwardly with a horizontal falcon bar (302), the two side surfaces of the retainer (1) are provided with side clamping grooves (105), the front of the retainer (1) is provided with a horizontal clamping groove (106), the horizontal falcon bar (302) of the U-shaped lock (3) is inserted into the horizontal clamping groove (106) of the retainer (1), and the side falcon bar (301) is inserted into the side clamping groove (105) of the retainer (1); A sealed cavity (205) is provided in the single slip (2), and the cavity (205) is extended around the inner side of the front arc (202).

2. A multi-stage combined slip according to claim 1, characterized in that: The single slip (2) is cut with cutting slits (204) that penetrate vertically on the front arc surface (202); the cutting slits (204) are evenly arranged on the front arc surface (202); the depth of the cutting slits (204) is 3 mm; and the width of the cutting slits (204) is 0.2 mm.

3. The multi-stage combined slip according to claim 1, characterized in that: The cavity (205) is filled with hydraulic oil.

4. The multi-stage combined slip according to claim 1, characterized in that: The inner end surface of the side bar (301) is inlaid with a permanent magnet block (303).

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