CN216381291U

CN216381291U - Cutting knife for oil field downhole pipe column cutting operation

Info

Publication number: CN216381291U
Application number: CN202123143756.6U
Authority: CN
Inventors: 祝君; 伏健
Original assignee: Tonghua Yuantong Petroleum Machinery Co ltd
Current assignee: Tonghua Yuantong Petroleum Machinery Co ltd
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2022-04-26
Anticipated expiration: 2031-12-15

Abstract

The utility model relates to an oil field well repairing operation tool, namely a cutting knife for cutting an oil field underground pipe column. The device comprises a joint and a mandrel connected with the joint; the clamping jaw is sleeved on the mandrel and the limiting sleeve is fixed by the shear pin; a tool holder connected with the lower part of the mandrel by an external thread and a nozzle connected with the internal thread; the knife rest cylinder is internally provided with a pressure spring, a piston and a check ring connected with the knife rest, the piston extends out of the check ring, and the outer end of the piston is connected with a cone which is connected with the jack catch in an action way. The cutter joint is connected with the lower end of the screw pump, and an operator can complete cutting operation only by controlling the displacement of the pump truck in the cutting process after entering the well; the tool can be withdrawn by stopping the pump, if the tool is blocked during withdrawal, the shear pin can be cut off by only lowering the drilling tool and applying a force more than or equal to 120kN downwards, the limiting sleeve and the clamping jaw are released, the tool can be withdrawn, and the whole operation is very simple and convenient.

Description

Cutting knife for oil field downhole pipe column cutting operation

Technical Field

The utility model relates to an oil field well repairing operation tool, namely a cutting knife for cutting an oil field underground pipe column.

Background

In the prior art, mechanical internal cutters are commonly used to perform downhole string cutting operations. The mechanical internal cutting knife is used for completing the cutting of the pipe column by using 3-5 blades by means of the downward placement of the drilling tool and the rotation power provided by the rotary disc.

The use of the mechanical internal cutting knife has certain limitations: firstly, the limitation of equipment needs a turntable to provide rotating power; secondly, because the mechanical internal cutter is limited by the size of the structure, the thickened parts of the coupling and the joint must be avoided during cutting; and cutting at any position cannot be realized; thirdly, the blades are generally made of high-speed steel, the hardness of the quenched blades is HRC58-62, and the blades are not suitable for P110-grade pipe columns with hard layers on the inner walls of the pipes.

The defects of the mechanical inner cutter are as follows: the control requirements of the lower discharging amount and the rotating speed are tighter during the operation of the mechanical internal cutting knife, the requirements on an operator are higher, and the phenomenon of damaging the tool tip of the blade often occurs during the operation, so that the failure of the cutting operation is caused.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide the cutting knife for the cutting operation of the underground pipe column of the oil field, which has the advantages of improved structure, safety, reliability, more convenient use and simpler operation.

The technical solution of the utility model is as follows: the cutter for oil field underground pipe column cutting operation is characterized by comprising a joint and a mandrel connected with the joint; the clamping jaw is sleeved on the mandrel and the limiting sleeve is fixed by the shear pin; a tool holder connected with the lower part of the mandrel by an external thread and a nozzle connected with the internal thread; the knife rest cylinder is internally provided with a pressure spring, a piston and a check ring connected with the knife rest, the piston extends out of the check ring, and the outer end of the piston is connected with a cone which is connected with the jack catch in an action way.

In the above scheme, the method further comprises:

the mandrel is provided with four symmetrical keys matched with the jaws.

Hard alloy blocks with milling and cutting functions and YD alloy combined abrasive materials are welded on the outer ends of the clamping jaws.

The utility model has the advantages that: 1. the cutter joint is connected with the lower end of the screw pump, and an operator can complete cutting operation only by controlling the displacement of the pump truck in the cutting process after entering the well; the tool can be withdrawn by stopping the pump, if the tool is blocked during withdrawal, the shear pin can be cut off by only lowering the drilling tool and applying a force more than or equal to 120kN downwards, the limiting sleeve and the clamping jaw are released, the tool can be withdrawn, and the whole operation is very simple and convenient. 2. The clamping jaw structure is supported by the cone, and the hard alloy block with high hardness and high wear resistance and YD alloy combined abrasive material with the grinding, milling and cutting functions, which is welded on the clamping jaw, is suitable for fish falling pipe columns made of any material, and the clamping jaw is not easy to damage. The radial expansion size of the claw is larger than the outer diameter of the fish falling coupling, so that the requirement of cutting any part of the fish falling can be met.

Embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of the present invention.

Fig. 2 is a schematic view of fig. 1 taken along a-a.

Figure 3 is a schematic view of the mandrel configuration.

Fig. 4 is a schematic view of fig. 3 taken along B-B.

Figure 5 is a diagrammatic view of the jaw configuration.

Fig. 6 is a schematic view of the structure of the stop collar.

Fig. 7 is a schematic view of a retainer ring structure.

Detailed Description

Referring to fig. 1-7, the part names are as follows: the device comprises a connector 1, a mandrel 2, a limiting sleeve 3, a shear pin 4, a clamping jaw 5, a cone 6, a check ring 7, a pressure spring 8, a piston 9, a piston outer sealing ring 10, a piston inner sealing ring 11, a set screw 12, a tool rest 13, a key 14, a nozzle 15, a hard alloy block 16 and YD alloy combined abrasive 17.

Referring to fig. 1-7, the cutter for cutting oil field underground pipe column comprises a joint 1 and a mandrel 2 connected with the joint 1; a jaw 5 sleeved on the mandrel 2 and a limit sleeve 3 fixed by a shear pin 4; a tool holder 13 and a nozzle 15 connected by internal thread to the lower part of the mandrel 2; a pressure spring 8, a piston 9 and a retainer ring 7 connected with the tool rest 13 are arranged in the tool rest 13, the piston 9 extends out of the retainer ring 7, and the outer end of the piston 9 is connected with a cone 6 which is in action connection with the clamping jaw 5. The spindle 2 is provided with four symmetrical keys 14 for the jaws 5. Hard alloy blocks 16 with milling and cutting functions and YD alloy combined abrasive materials 17 are welded on the outer ends of the clamping jaws 5.

The joint 1: the upper part is provided with a drill rod male buckle connected with the drilling tool, the lower drill rod female buckle is connected with the mandrel 2, and a circulating water hole is arranged in the lower drill rod female buckle.

And (3) a mandrel 2: referring to fig. 1 and 3, the upper drill rod male buckle is connected with the connector 1; four symmetrical keys 14 are processed on the mandrel 2 near the maximum outer diameter of the upper part and matched with the clamping jaws 5, and are used for guiding and transmitting torque to drive the clamping jaws 5 to rotate; the external thread at the lower part of the mandrel 2 is connected with a tool rest 13, the internal thread is connected with a nozzle 15, and other parts are sleeved on the mandrel 2.

And (3) a limiting sleeve: referring to fig. 1 and 6, the shear pin 4 is fixed to the mandrel 2 to define the axial position of the jaws 5 on the mandrel 2, under conditions such that the jaws 5 are only radially expandable and not axially movable. When the shear pin 4 is sheared, the axial movement of the jaw 5 can be released.

And (4) shearing nails: is used for fixing the limiting sleeve 3, when the limiting sleeve is sheared off, the claws 5 can be released, and the aim of loosening the claws 5 to release fish falls is achieved. The limiting sleeve 3 is sleeved on the mandrel 2 and fixed by the shear pin 4, when the shear pin 4 is sheared off, the limiting sleeve 3 and the claw 5 are completely released, and the tool can be easily withdrawn from the fallen fish.

The clamping jaw 5: referring to fig. 1 and 5, the key 14 sleeved on the mandrel 2 is in a cylindrical four-lobe shape with elasticity in structural view, the taper of the inner conical surface at the lower part is consistent with that of the outer conical surface of the cone 6, and hard alloy blocks 16 and YD alloy combined abrasive 17 are welded on the outer surfaces of the four lobes at the lower part and used for milling and cutting the fish.

And (6) cone body: the lower part is provided with internal threads connected with a piston 9, and the upper part can provide radial expansion force for the claws 5 due to the matched external conical surfaces of the claws 5.

And (7) a retainer ring: referring to fig. 1 and 7, the piston 9 is sleeved with a cylindrical structure, and the cylindrical structure is externally connected with the internal thread of the tool holder 13 through a thread, so that the pressure spring 8 is limited in an annular space between the piston 9 and the tool holder 13.

And (3) compression spring 8: is mounted in compression on the piston 9 and serves to cushion the piston 9 as it moves upwardly and to provide a restoring axial force to the piston 9.

Piston 9: the upper end is provided with an external thread which is connected with the cone 6 and sleeved on the mandrel 2, the lower part of the upper end is internally and externally provided with a piston outer sealing ring 10 and a piston inner sealing ring 11 which can move along the axial direction of the mandrel 2 in a tool rest 13. When the fish-cutting machine moves upwards along the mandrel 2 under the action of the pressure of the end face of the piston 9, the cone 6 is driven to move upwards to gradually contact the claws 5, so that the claws 5 radially expand along the conical surface, and fish is ground and cut. The cone 6 provides power for the jaw 5, and the piston 9 and the pressure spring 8 with the reset function.

A tool holder 13: the lower part is provided with internal threads which are connected with the internal threads at the lower end of the mandrel 2 and locked by a set screw 12, and the upper cavity is provided with a compression spring 8 and a piston 9 and is fixed by the compression spring 7 and can be regarded as a sealing cylinder sleeve.

Nozzle 15: the external thread of the nozzle is connected with the internal thread at the lower end of the mandrel 2 and is fixed by the set screw 12, the small hole in the nozzle plays a throttling role, and the nozzle 15 has good wear-resisting effect after integral quenching treatment.

The cutting knife is connected with the screw pump for use, and the rotary power and the axial power of the cutting knife are all from the screw pump driven by the ground pump truck, so that a saved rotary table is simpler to operate, and only the displacement of the pump truck needs to be controlled. The cutting knife clamping jaw 5 is welded with the hard alloy blocks 16 and YD alloy combined abrasive materials 17 which have high hardness and high wear resistance and have the functions of milling and cutting, and can be suitable for fish falling pipe columns made of any materials, and the clamping jaw 5 is not easy to damage. The radial expansion size of the claw 5 is larger than the outer diameter of the fish falling coupling, so that the requirement of cutting any part of the fish falling can be met.

When the cutting knife is operated, the cutting knife is connected to the lower end of a screw pump and is put into a well, fish enters the position needing to be cut, the pump is started, the rotating speed of the screw pump is ensured to be 60-80 r/m, the working pressure difference is 3-5MPa, a piston 9 drives a cone 6 to move upwards to push a clamping jaw 5 to radially expand, milling and cutting are started under the rotating power of the screw pump, and the operation time is generally about 30 minutes. When the milling and cutting are finished, stopping the pump, and lifting the drilling tool to withdraw the tool; if the drilling tool is lifted up and is not moved, the drilling tool is lowered down, a force larger than or equal to 120kN is applied downwards, the shear pins 4 are sheared, the limiting sleeve 3 is released, the clamping jaws 5 can be retracted, and then the drilling tool is lifted up and can be withdrawn from the fish.

Claims

1. The cutter for the cutting operation of the oil field underground pipe column is characterized by comprising a joint (1) and a mandrel (2) connected with the joint (1); a jaw (5) sleeved on the mandrel (2) and a limit sleeve (3) fixed by a shear pin (4); a tool holder (13) connected with the lower part of the mandrel (2) by external threads and a nozzle (15) connected with the internal threads; a pressure spring (8), a piston (9) and a retainer ring (7) connected with the tool rest (13) are arranged in the tool rest (13) cylinder, the piston (9) extends out of the retainer ring (7), and the outer end of the piston (9) is connected with a cone (6) which is in action connection with the clamping jaw (5).

2. The cutting knife for cutting oilfield tubular strings according to claim 1, characterized in that the mandrel (2) is provided with four symmetrical keys (14) which are matched with the jaws (5).

3. The cutter for cutting oil field downhole tubular strings according to claim 1 or 2, characterized in that the outer end of the jaw (5) is welded with hard alloy blocks (16) and YD alloy combined abrasive materials (17) having milling and cutting functions.