CN109441388B - Catheter salvaging device and salvaging method - Google Patents

Abstract

The invention discloses a catheter salvaging device and a salvaging method, which comprises a base and at least four salvaging heads, wherein the center of the top surface of the base is provided with a hoisting head, the salvaging heads are uniformly arranged around the base, the side surface of the outer circumference of the base is uniformly provided with a first supporting arm, the top surface of the salvaging head is fixedly connected with a second supporting arm through a fixing rod, the first supporting arm and the second supporting arm are movably connected through a telescopic mechanism and a horizontal supporting rod, and the horizontal supporting rod is uniformly distributed around the telescopic mechanism. The salvaging method comprises the following steps: the method comprises the steps of base processing, salvage head processing, first support arm and second support arm processing, component mounting and conduit salvage. The invention has simple structure and strong practicability, can not only adjust the distance between the salvaging head and the base according to the caliber of different catheters, meet the salvaging of the catheters with different calibers, improve the use range and flexibility of the catheter salvaging device, but also has convenient manufacture, simple and convenient operation and extremely high success rate.

Description

Catheter salvaging device and salvaging method

Technical Field

The invention relates to a catheter salvaging device and a salvaging method.

Background

In the process of bored pile body concrete pouring, the condition that the guide pipe falls into a pile hole due to old and worn threads or careless construction and the like sometimes occurs, and the guide pipe is generally salvaged and sleeved by adopting a steel wire rope or a steel bar. The method for salvaging the conduit is as follows: rope loop method, hook method, etc.; the methods are not satisfactory in the salvaging process of the fallen guide pipe, because the outer edge of the guide pipe with the threaded connection is very small, the method is difficult to work in the treatment process, the gas carrying component is too large, the specific gravity of slurry is too large, the common method cannot meet the requirement due to dead weight, and the guide pipe opening is difficult to touch in the descending process.

Disclosure of Invention

The invention aims to provide a catheter salvage device and a salvage method for overcoming the defects of the prior art, which not only can adjust the distance between a salvage head and a base according to the calibers of different catheters to meet the salvage of the catheters with different calibers, but also can improve the use range and flexibility of the catheter salvage device, and has the advantages of convenient manufacture, simple and convenient operation and extremely high success rate.

In order to solve the technical problems, the invention adopts the following technical scheme:

a catheter fishing device, characterized in that: the fishing device comprises a base and at least four fishing heads, wherein the center of the top surface of the base is provided with a hoisting head, the fishing heads are uniformly arranged around the base, the outer circumferential side surface of the base is uniformly provided with a first supporting arm, the top surface of the fishing head is fixedly connected with a second supporting arm through a fixing rod, the first supporting arm is movably connected with the second supporting arm through a telescopic mechanism and a horizontal supporting rod, and the horizontal supporting rods are uniformly distributed around the telescopic mechanism; through the design of four salvage heads, can carry out the average distribution to the atress of each salvage head when salvaging the pipe, improve the clamping dynamics of salvage device to the pipe, make salvage device can touch the pipe mouth fast simultaneously, improve salvage effect, the joint strength between salvage head and the base has been improved in the design of first support arm and second support arm, prevent to take place to crookedly influence salvage effect of salvage device, telescopic machanism's design, can adjust the interval between salvage head and the base according to the bore of different pipes, satisfy the pipe salvage of different bore sizes, the application range and the flexibility of pipe salvage device have been improved, horizontal bracing piece has improved the stability and the reliability of being connected between first support arm and the second support arm, improve salvage device's bulk strength, can guarantee simultaneously that first support arm and second support arm are located same straight line, make each salvage head atress balanced, stability when improving salvage.

Further, the hoisting head is provided with the recess up, and the rotation is connected with the dwang in the recess, and the design of dwang can be connected the base through hawser and outside lifting device, satisfies the salvage needs of different degree of depth, improves fishing device's working range, and the installation needs of different size dwang can be satisfied in the design of recess.

Further, telescopic machanism includes telescopic link and spur gear, telescopic link's one end fixed connection is on the terminal surface of second support arm, telescopic link's the other end is spacing in the second spacing inslot, the second spacing inslot is located first support arm, telescopic link and second spacing inslot assorted, through spur gear's rotation, can drive telescopic link along second spacing inslot horizontal migration, and then adjust the interval between second support arm and the first support arm, further adjust the interval between the salvage head, satisfy the pipe salvage demand of different diameter sizes.

Further, be provided with logical groove on the flexible strip, be provided with the rack on the medial surface of logical groove, lead to inslot vertical being provided with the spur gear, spur gear and rack intermeshing, the spur gear rotates through the pivot and connects in first support arm, and the top of pivot is provided with the nut, and the nut is located the top surface of first support arm, through rotating the nut, drives the spur gear through the pivot and rotates, and then adjusts the rack and remove, makes flexible strip follow the design direction and removes.

Further, be provided with the tooth's socket in the first support arm, the tooth's socket is located directly over the spur gear, and spur gear and tooth's socket phase-match, after the second support arm moved to the settlement position, pull up the nut, can be with the spur gear spacing fixed in the tooth's socket, and then realize the location to the rack.

Further, the locating holes are horizontally formed in the first supporting arms, the locating holes are symmetrically formed in the periphery of the second limiting groove, the horizontal supporting rods are matched with the locating holes, the horizontal supporting rods can move back and forth along the locating holes, and stability and strength of connection between the first supporting arms and the second supporting arms are improved.

Further, the outer side face of the telescopic strip is provided with scales, the precision of movement of each salvaging head is improved through the scales, accurate clamping and positioning of the catheters with different diameters are achieved, and the salvaging effect is improved.

Further, the salvage head is provided with the clamping groove downwards, from last down evenly distributed has first spacing groove on the medial surface in clamping groove, be provided with at least three first spacing groove on the horizontal straight line of same side, first spacing groove on two relative sides is located same horizontal plane, be connected with the latch segment through the spring removal in the first spacing groove, latch segment and first spacing groove assorted, the terminal surface of latch segment is the inclined plane, when salvage device moves downwards, the lateral wall of pipe extrudees the latch segment through the spring in the first spacing groove, when salvage device moves upwards and lifts by crane the pipe, the latch segment stretches out under the effect of spring to the bottom surface of the outer edge of pipe is detained, stability and reliability when improving salvage.

Further, be provided with the wedge face on the bottom lateral surface of salvaging the head, the design of wedge face is convenient for salvage the device and can fall fast, reduces the resistance.

The method for salvaging the conduit by using the conduit salvaging device is characterized by comprising the following steps of:

1) Base processing

a. Firstly, determining the size of a base according to the design requirement of a drawing, forming the required base through casting molding, and carrying out deburring treatment on the surface of the base;

b. then installing a hoisting head with a rotating block at the center of the top surface of the base, observing the balance state of the rotating block during rotation, adjusting the rotating block to rotate around a horizontal shaft, and coating lubricating oil on the contact surface of the rotating block and a cable;

2) Fishing head processing

a. Firstly, determining the size of a salvaging head according to the design requirement of a drawing, forming the required salvaging head through casting molding, polishing the inner side surfaces of a salvaging head clamping groove through a handheld polisher to keep the two inner side surfaces of the clamping groove parallel, and vertically installing a fixing rod in the center of the top surface of the salvaging head;

b. then vertically downwards and equidistantly determining the position of a first limit groove along the outer side surface of the fishing head, drilling the first limit groove through a drilling machine, and opening the first limit groove until all the designed first limit grooves are completely opened;

c. selecting a locking block according to the size of the first limit groove, polishing the outer side surface of the locking block, polishing the end surface of the locking block, which is in contact with the guide pipe, to form an inclined surface, wherein the inclined angle of the inclined surface is 60-75 degrees, and connecting the other end of the locking block with the sealing block through a spring;

d. then the locking blocks are inserted into the first limit grooves, the sealing blocks are pushed to the set positions of the first limit grooves, the sealing blocks and the first limit grooves are sealed through sealing glue, and molten iron is poured to the outer sides from the positions of the sealing blocks along the first limit grooves to seal until the locking blocks are flush with the outer side surfaces of the salvaging heads, and all the locking blocks are installed in sequence;

e. finally, marking along the outer side surface of the salvaging head according to the length and the size of the wedge-shaped surface, firstly cutting by a cutting machine, and polishing by a polisher when the cutting is 5mm different from the designed thickness until the required size of the wedge-shaped surface is reached;

3) Processing of the first support arm and the second support arm

a. Firstly, determining the lengths of a first support arm and a second support arm according to the designed movement stroke of the second support arm, and forming the required first support arm and the required second support arm through casting molding;

b. then, a second limiting groove and positioning holes are formed in the end face of the first supporting arm along the horizontal direction, so that the positioning holes are symmetrically distributed around the second limiting groove, the depth of the positioning holes is ensured to be 10-15 mm greater than that of the second limiting groove, a blind hole is formed in the vertical direction of the first supporting arm, and a tooth slot is formed between the blind hole and the top surface of the second limiting groove;

c. then processing a horizontal support rod and a telescopic bar according to the sizes of the positioning hole and the second limiting groove, vertically forming a through groove along the horizontal direction of the telescopic bar, horizontally and fixedly mounting a rack on one inner side surface of the through groove, and arranging scales along the outer side surface of the telescopic bar;

4) Component mounting

Firstly, fixing the end parts of the processed first support arms on the outer circumferential side surface of a base, keeping the angle and the distance between two adjacent first support arms equal, then connecting the processed second support arms with a fixed rod to fix a salvaging head on the bottom surface of the second support arms, fixing one ends of a telescopic bar and four horizontal support rods on the end surfaces of the second support arms, respectively inserting the other ends of the horizontal support rods and the telescopic bar into a positioning hole and a second limiting groove, simultaneously placing a spur gear meshed with a rack in the through groove, finally inserting a rotating shaft for driving a nut along a blind hole, inserting the bottom of the first support arm after penetrating through the axis of the spur gear, rotating the nut to observe the movement condition of the second support arms, and ensuring that the movement distance of each second support arm is equal;

5) Catheter salvaging

The method comprises the steps of firstly connecting a whole conduit salvaging device with external hoisting equipment through a cable, then adjusting the opening area of the conduit salvaging device according to the aperture of a pile body of a bored pile and the wall thickness and the diameter of the conduit, driving a rack to move by rotating a nut, further driving a telescopic bar and a horizontal supporting rod to move, determining the extending length of a second supporting arm according to scales on the side face of the telescopic bar, pulling up the nut after the salvaging heads reach the set length, enabling the spur gear to be limited and fixed in a tooth slot, adjusting the positions of the rest salvaging heads in sequence according to the scales until the horizontal displacement of the four salvaging heads is equal, then lowering the conduit salvaging device through the external hoisting equipment, and lowering the conduit salvaging device into the pile body of the bored pile, wherein after the conduit salvaging device hits the conduit, a clamping groove on the salvaging head is clamped into the side wall of the conduit, and continuously moves downwards under the gravity action of the conduit salvaging device until the top face of the pipe mouth clamping groove of the conduit is started, and finally the external hoisting equipment is lifted through the cable, and a limiting ring on the conduit is directly clamped on the top face of a locking block, so that the salvaging of the conduit is achieved.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

1. by the design of the four salvage heads, the stress of each salvage head can be evenly distributed when the conduit is salvaged, so that the clamping force of the salvage device on the conduit is improved, and meanwhile, the salvage device can quickly touch the conduit opening, so that the salvage effect is improved;

2. the design of the first support arm and the second support arm improves the connection strength between the salvaging head and the base, and prevents bending from influencing the salvaging effect of the salvaging device;

3. the telescopic mechanism is designed, so that the distance between the salvaging head and the base can be adjusted according to the calibers of different catheters, the salvaging of the catheters with different calibers is met, and the application range and flexibility of the catheter salvaging device are improved;

4. the horizontal support rod improves the stability and reliability of connection between the first support arm and the second support arm, improves the overall strength of the salvaging device, and can ensure that the first support arm and the second support arm are positioned on the same straight line, so that the stress of each salvaging head is balanced, and improves the stability during salvaging;

5. the salvaging method is simple to operate and extremely high in success rate, and the salvaging efficiency of the catheter is greatly improved.

The invention has simple structure and strong practicability, can not only adjust the distance between the salvaging head and the base according to the caliber of different catheters, meet the salvaging of the catheters with different calibers, improve the use range and flexibility of the catheter salvaging device, but also has convenient manufacture, simple and convenient operation and extremely high success rate.

Drawings

The invention is further described below with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a pipe fishing device and a fishing method according to the present invention.

Fig. 2 is a partial enlarged view of i in fig. 1.

FIG. 3 is a schematic view of the fishing head according to the present invention.

Fig. 4 is a bottom view of fig. 3.

Fig. 5 is a schematic view of the connection between the telescopic bar and the first support arm in the present invention.

Fig. 6 is a schematic structural view of a first support arm according to the present invention.

Fig. 7 is a schematic structural view of a hoisting head in the present invention.

In the figure: 1. a base; 2. hoisting the head; 3. a fishing head; 4. a first support arm; 5. a second support arm; 6. a fixed rod; 7. clamping grooves; 8. a wedge surface; 9. a screw cap; 10. a horizontal support bar; 11. a telescoping strip; 12. a through groove; 13. a rack; 14. a locking block; 15. a first limit groove; 16. a spring; 17. the second limit groove; 18. spur gears; 19. a rotating shaft; 20. tooth slots; 21. positioning holes; 22. a groove; 23. and rotating the block.

Detailed Description

As shown in fig. 1 to 7, the catheter fishing device of the invention comprises a base 1 and at least four fishing heads 3, wherein a hoisting head 2 is arranged at the center of the top surface of the base 1, the hoisting head 2 is upwards provided with a groove 22, a rotating block 23 is rotationally connected in the groove 22, the base 1 can be connected with external hoisting equipment through a cable by the design of the rotating block 23, the fishing requirements of different depths are met, the working range of the fishing device is improved, and the installation requirements of the rotating blocks 23 with different sizes can be met by the design of the groove 22.

The salvage head 3 evenly sets up around base 1, salvage head 3 is provided with clamping groove 7 downwards, evenly distributed has first spacing groove 15 from last down on the medial surface of clamping groove 7, be provided with at least three first spacing groove 15 on the horizontal straight line of same side, first spacing groove 15 on two relative sides are located same horizontal plane, be connected with latch segment 14 through the spring 16 removal in the first spacing groove 15, latch segment 14 and first spacing groove 15 assorted, the terminal surface of latch segment 14 is the inclined plane, when salvage device moves downwards, the lateral wall of pipe extrudees latch segment 14 through spring 16 towards first spacing groove 15 in, when salvage device moves upwards and lifts by crane the pipe, latch segment 14 stretches out under the effect of spring 16, and buckle the bottom surface of pipe outward flange, stability and reliability when improving salvage, be provided with wedge 8 on the bottom lateral surface of salvage head 3, wedge 8's design is convenient for salvage device can fall fast, reduce the resistance.

The first supporting arm 4 is uniformly arranged on the outer circumferential side surface of the base 1, the second supporting arm 5 is fixedly connected to the top surface of the fishing head 3 through the fixing rod 6, the first supporting arm 4 is movably connected with the second supporting arm 5 through a telescopic mechanism and the horizontal supporting rod 10, the horizontal supporting rod 10 is uniformly distributed around the telescopic mechanism, the telescopic mechanism comprises a telescopic strip 11 and a spur gear 18, one end of the telescopic strip 11 is fixedly connected to the end surface of the second supporting arm 5, the other end of the telescopic strip 11 is limited in a second limiting groove 17, the second limiting groove 17 is positioned in the first supporting arm 4, the telescopic strip 11 is matched with the second limiting groove 17, the telescopic strip 11 can be driven to horizontally move along the second limiting groove 17 through the rotation of the spur gear 18, the distance between the second supporting arm 5 and the first supporting arm 4 is further adjusted, the distance between the fishing heads 3 is further adjusted, the fishing requirements of the guide pipes with different diameters are met, the telescopic bar 11 is provided with a through groove 12, one inner side surface of the through groove 12 is provided with a rack 13, a spur gear 18 is vertically arranged in the through groove 12, the spur gear 18 is meshed with the rack 13, the spur gear 18 is rotationally connected in the first supporting arm 4 through a rotating shaft 19, the top end of the rotating shaft 19 is provided with a nut 9, the nut 9 is positioned on the top surface of the first supporting arm 4, the spur gear 18 is driven to rotate through the rotating shaft 19 through the rotating shaft 9, the rack 13 is further regulated to move, the telescopic bar 11 moves along the design direction, a tooth groove 20 is arranged in the first supporting arm 4, the tooth groove 20 is positioned right above the spur gear 18, the spur gear 18 is matched with the tooth groove 20, after the second supporting arm 5 moves to a set position, the nut 9 is pulled up, the spur gear 18 can be limited in the tooth groove 20 to be fixed, and then the positioning of the rack 13 is realized, the positioning holes 21 are horizontally formed in the first supporting arm 4, the positioning holes 21 are symmetrically formed in the periphery of the second limiting groove 17, the horizontal supporting rods 10 are matched with the positioning holes 21, the horizontal supporting rods 10 can move back and forth along the positioning holes 21, stability and strength of connection between the first supporting arm 4 and the second supporting arm 5 are improved, scales are arranged on the outer side face of the telescopic strip 11, moving precision of each fishing head 3 is improved due to the scale, accurate clamping and positioning of different-caliber catheters are achieved, and fishing effect is improved; through the design of four salvage heads 3, can carry out the average distribution to the atress of each salvage head 3 when salvaging the pipe, improve the clamping dynamics of salvage device to the pipe, make salvage device can touch the pipe mouth fast simultaneously, improve salvage effect, the joint strength between salvage head 3 and the base 1 has been improved in the design of first support arm 4 and second support arm 5, prevent to take place crookedly and influence salvage device's salvage effect, telescopic machanism's design, can adjust the interval between salvage head 3 and the base 1 according to the bore of different pipes, satisfy the pipe salvage of different bore sizes, the application range and the flexibility of pipe salvage device have been improved, horizontal support pole 10 has improved stability and the reliability of being connected between first support arm 4 and the second support arm 5, improve salvage device's bulk strength, can guarantee simultaneously that first support arm 4 and second support arm 5 are located same straight line, make each salvage head 3 atress balanced, stability when improving salvage.

The method for salvaging the conduit by using the conduit salvaging device comprises the following steps:

1) Base processing

a. Firstly, determining the size of a base 1 according to the design requirement of a drawing, forming the required base 1 through casting molding, and carrying out deburring treatment on the surface of the base 1;

b. then installing a hoisting head 2 with a rotating block 23 at the center of the top surface of the base 1, observing the balance state of the rotating block 23 during rotation, adjusting the rotating block 23 to rotate around a horizontal shaft, and coating lubricating oil on the contact surface of the rotating block 23 and a cable;

2) Fishing head processing

a. Firstly, determining the size of a salvage head 3 according to the design requirement of a drawing, forming the required salvage head 3 through casting molding, polishing the inner side surfaces of a clamping groove 7 of the salvage head 3 through a handheld polisher, keeping the two inner side surfaces of the clamping groove 7 in parallel, and simultaneously vertically installing a fixing rod 6 in the center of the top surface of the salvage head 3;

b. then the position of the first limit groove 15 is vertically and downwards determined at equal intervals along the outer side surface of the fishing head 3, the first limit groove 15 is drilled through a drilling machine, and the first limit groove 15 is opened until all the designed first limit grooves 15 are opened;

c. selecting a locking block 14 according to the size of the first limit groove 15, polishing the outer side surface of the locking block 14, polishing the end surface of the locking block 14, which is in contact with the guide pipe, to form an inclined surface, wherein the inclined angle of the inclined surface is 60-75 degrees, and connecting the other end of the locking block 14 with a sealing block through a spring 16;

d. then the locking blocks 14 are inserted into the first limit grooves 15 firstly, then the sealing blocks are pushed to the set positions of the first limit grooves 15, the sealing blocks and the first limit grooves 15 are sealed through sealing glue, and then molten iron is poured to the outside from the positions of the sealing blocks along the first limit grooves 15 for sealing until the locking blocks are flush with the outer side surfaces of the fishing heads 3, and all the locking blocks 14 are installed in sequence;

e. finally, marking along the outer side surface of the fishing head 3 according to the length and the size of the wedge-shaped surface 8, firstly cutting by a cutting machine, and polishing by a polisher when the cutting is 5mm different from the designed thickness until the required size of the wedge-shaped surface 8 is achieved;

3) Processing of the first support arm and the second support arm

a. Firstly, determining the length of a first support arm 4 and a second support arm 5 according to the designed movement stroke of the second support arm 5, and forming the required first support arm 4 and the second support arm 5 through casting molding;

b. then, a second limiting groove 17 and a positioning hole 21 are formed in the end face of the first supporting arm 4 along the horizontal direction, so that the positioning holes 21 are symmetrically distributed around the second limiting groove 17, the depth of the positioning hole 21 is ensured to be 10-15 mm greater than that of the second limiting groove 17, a blind hole is formed in the vertical direction of the first supporting arm 4, and a tooth slot 20 is formed between the blind hole and the top face of the second limiting groove 17;

c. then processing the horizontal support rod 10 and the telescopic bar 11 according to the sizes of the positioning hole 21 and the second limiting groove 17, vertically arranging the through groove 12 along the horizontal direction of the telescopic bar 11, horizontally and fixedly arranging the rack 13 on one inner side surface of the through groove 12, and arranging scales along the outer side surface of the telescopic bar 11;

4) Component mounting

Firstly, fixing the end parts of the processed first support arms 4 on the outer circumferential side surface of the base 1, keeping the angle and the distance between two adjacent first support arms 4 equal, then connecting the processed second support arms 5 with the fixed rod 6 to fix the fishing head 3 on the bottom surface of the second support arms 5, fixing one ends of the telescopic bars 11 and the four horizontal support rods 10 on the end surfaces of the second support arms 5, inserting the other ends of the horizontal support rods 10 and the telescopic bars 11 into the positioning holes 21 and the second limiting grooves 17 respectively, simultaneously placing the spur gears 18 meshed with the racks 13 in the through grooves 12, finally inserting the rotating shafts 19 for driving the nuts 9 along blind holes, inserting the bottoms of the first support arms 4 after penetrating the axes of the spur gears 18, rotating the nuts 9 to observe the movement condition of the second support arms 5, and ensuring that the movement distance of each second support arm 5 is equal;

5) Catheter salvaging

Firstly, the whole conduit fishing device is connected with external hoisting equipment through a cable, then the opening area of the conduit fishing device is adjusted according to the aperture of a pile body of a bored pile and the wall thickness and the diameter of the conduit, a nut 9 is rotated, a spur gear 18 drives a rack 13 to move, further drives a telescopic bar 11 and a horizontal support bar 10 to move, the extension length of a second support arm 5 is determined according to the scales on the side surface of the telescopic bar 11, after the fishing head 3 reaches a set length, the nut 9 is pulled up, the spur gear 18 is limited and fixed in a tooth socket 20, the positions of the rest fishing heads 3 are sequentially adjusted according to the scales until the horizontal displacement of the four fishing heads 3 is equal, then the conduit fishing device is lowered through the external hoisting equipment, the conduit fishing device is lowered into the pile body of the bored pile, after the conduit fishing device hits the conduit, a clamping groove 7 on the fishing head 3 is clamped into the side wall of the conduit, and continues to move downwards under the gravity action of the conduit fishing device until the pipe orifice of the conduit abuts against the top surface of the clamping groove 7, finally the external hoisting equipment is started, and a limiting ring on the conduit is directly clamped on the top surface of a locking block 14 through the cable.

The above is only a specific embodiment of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions or modifications made on the basis of the present invention to achieve substantially the same technical effects are included in the scope of the present invention.

Claims (3)

1. A catheter fishing device, characterized in that: the fishing device comprises a base and at least four fishing heads, wherein lifting heads are arranged at the center of the top surface of the base, the fishing heads are uniformly arranged around the base, first supporting arms are uniformly arranged on the lateral surface of the outer circumference of the base, the top surface of the fishing head is fixedly connected with second supporting arms through fixing rods, the first supporting arms and the second supporting arms are movably connected through telescopic mechanisms and horizontal supporting rods, the horizontal supporting rods are uniformly distributed around the telescopic mechanisms, grooves are formed in the upward direction of the lifting heads, and rotating blocks are rotationally connected in the grooves; the telescopic mechanism comprises a telescopic bar and a spur gear, one end of the telescopic bar is fixedly connected to the end face of the second supporting arm, the other end of the telescopic bar is limited in a second limiting groove, the second limiting groove is located in the first supporting arm, and the telescopic bar is matched with the second limiting groove; the telescopic bar is provided with a through groove, one inner side surface of the through groove is provided with a rack, the through groove is internally and vertically provided with a spur gear, the spur gear is meshed with the rack, the spur gear is rotationally connected in the first supporting arm through a rotating shaft, the top end of the rotating shaft is provided with a nut, and the nut is positioned on the top surface of the first supporting arm; a tooth groove is arranged in the first supporting arm, the tooth groove is positioned right above the spur gear, and the spur gear is matched with the tooth groove; the first support arm is horizontally provided with positioning holes, the positioning holes are symmetrically arranged around the second limiting groove, and the horizontal support rod is matched with the positioning holes; the outer side surface of the telescopic strip is provided with scales; the fishing head is provided with a clamping groove downwards, first limit grooves are uniformly distributed on the inner side surface of the clamping groove from top to bottom, at least three first limit grooves are arranged on the horizontal straight line of the same side surface, the first limit grooves on two opposite side surfaces are positioned in the same horizontal plane, locking blocks are movably connected in the first limit grooves through springs, the locking blocks are matched with the first limit grooves, and the end surfaces of the locking blocks are inclined surfaces.

2. A catheter fishing device as defined in claim 1, wherein: the outer side surface of the bottom of the salvaging head is provided with a wedge-shaped surface.

3. A method of fishing a conduit using a conduit fishing device as defined in claim 1, comprising the steps of:

1) Base processing

a. Firstly, determining the size of a base according to the design requirement of a drawing, forming the required base through casting molding, and carrying out deburring treatment on the surface of the base;

b. then installing a hoisting head with a rotating block at the center of the top surface of the base, observing the balance state of the rotating block during rotation, adjusting the rotating block to rotate around a horizontal shaft, and coating lubricating oil on the contact surface of the rotating block and a cable;

2) Fishing head processing

a. Firstly, determining the size of a salvaging head according to the design requirement of a drawing, forming the required salvaging head through casting molding, polishing the inner side surfaces of a salvaging head clamping groove through a handheld polisher to keep the two inner side surfaces of the clamping groove parallel, and vertically installing a fixing rod in the center of the top surface of the salvaging head;

b. then vertically downwards and equidistantly determining the position of a first limit groove along the outer side surface of the fishing head, drilling the first limit groove through a drilling machine, and opening the first limit groove until all the designed first limit grooves are completely opened;

c. selecting a locking block according to the size of the first limit groove, polishing the outer side surface of the locking block, polishing the end surface of the locking block, which is in contact with the guide pipe, to form an inclined surface, wherein the inclined angle of the inclined surface is 60-75 degrees, and connecting the other end of the locking block with the sealing block through a spring;

d. then the locking blocks are inserted into the first limit grooves, the sealing blocks are pushed to the set positions of the first limit grooves, the sealing blocks and the first limit grooves are sealed through sealing glue, and molten iron is poured to the outer sides from the positions of the sealing blocks along the first limit grooves to seal until the locking blocks are flush with the outer side surfaces of the salvaging heads, and all the locking blocks are installed in sequence;

e. finally, marking along the outer side surface of the salvaging head according to the length and the size of the wedge-shaped surface, firstly cutting by a cutting machine, and polishing by a polisher when the cutting is 5mm different from the designed thickness until the required size of the wedge-shaped surface is reached;

3) Processing of the first support arm and the second support arm

a. Firstly, determining the lengths of a first support arm and a second support arm according to the designed movement stroke of the second support arm, and forming the required first support arm and the required second support arm through casting molding;

b. then, a second limiting groove and positioning holes are formed in the end face of the first supporting arm along the horizontal direction, so that the positioning holes are symmetrically distributed around the second limiting groove, the depth of the positioning holes is ensured to be 10-15 mm greater than that of the second limiting groove, a blind hole is formed in the vertical direction of the first supporting arm, and a tooth slot is formed between the blind hole and the top surface of the second limiting groove;

c. then processing a horizontal support rod and a telescopic bar according to the sizes of the positioning hole and the second limiting groove, vertically forming a through groove along the horizontal direction of the telescopic bar, horizontally and fixedly mounting a rack on one inner side surface of the through groove, and arranging scales along the outer side surface of the telescopic bar;

4) Component mounting

Firstly, fixing the end parts of the processed first support arms on the outer circumferential side surface of a base, keeping the angle and the distance between two adjacent first support arms equal, then connecting the processed second support arms with a fixed rod to fix a salvaging head on the bottom surface of the second support arms, fixing one ends of a telescopic bar and four horizontal support rods on the end surfaces of the second support arms, respectively inserting the other ends of the horizontal support rods and the telescopic bar into a positioning hole and a second limiting groove, simultaneously placing a spur gear meshed with a rack in the through groove, finally inserting a rotating shaft for driving a nut along a blind hole, inserting the bottom of the first support arm after penetrating through the axis of the spur gear, rotating the nut to observe the movement condition of the second support arms, and ensuring that the movement distance of each second support arm is equal;

5) Catheter salvaging

The method comprises the steps of firstly connecting a whole conduit salvaging device with external hoisting equipment through a cable, then adjusting the opening area of the conduit salvaging device according to the aperture of a pile body of a bored pile and the wall thickness and the diameter of the conduit, driving a rack to move by rotating a nut, further driving a telescopic bar and a horizontal supporting rod to move, determining the extending length of a second supporting arm according to scales on the side face of the telescopic bar, pulling up the nut after the salvaging heads reach the set length, enabling the spur gear to be limited and fixed in a tooth slot, adjusting the positions of the rest salvaging heads in sequence according to the scales until the horizontal displacement of the four salvaging heads is equal, then lowering the conduit salvaging device through the external hoisting equipment, and lowering the conduit salvaging device into the pile body of the bored pile, wherein after the conduit salvaging device hits the conduit, a clamping groove on the salvaging head is clamped into the side wall of the conduit, and continuously moves downwards under the gravity action of the conduit salvaging device until the top face of the pipe mouth clamping groove of the conduit is started, and finally the external hoisting equipment is lifted through the cable, and a limiting ring on the conduit is directly clamped on the top face of a locking block, so that the salvaging of the conduit is achieved.