Fishing spear

Abstract

The utility model relates to a fishing spear, which is used for fishing fish from a casing pipe of an oil well and comprises a drill rod joint, the spear rod is coaxially connected below the drill rod joint; the eccentric positioning piece comprises a peripheral part far away from the axis of the eccentric positioning piece in the radial direction, and the spear rod is connected to the peripheral part and extends in the axial direction of the eccentric positioning piece; a first preset distance is formed between the axis of the spear rod and the axis of the eccentric positioning piece; and when the fishing spear downwards extends into the sleeve, the outer wall of the eccentric positioning piece is in clearance fit with the inner wall of the sleeve in the radial direction of the sleeve, so that the position of the spear rod in the sleeve is limited in the radial direction of the sleeve. According to the utility model, the fish attached to the edge of the sleeve in the well can be accurately positioned and fished; and the spear rod is coaxially connected with the drill rod joint, so that when the drill rod is lifted up to drive a fish, an eccentric effect is not generated, the fish does not deflect in a shaft, and scraping and clamping between the fish and the inner wall of the shaft are avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to the downhole workover operation fishing tool technical field of petroleum industry, in particular to a fishing spear. BACKGROUND

[0002] In the oilfield oil, gas, water well workover operation, sometimes multiple pipe class dropouts fall into the well in succession, at this time, the pipe class dropouts falling in later will slide along the space between the pipe class dropouts falling in first and the casing, resulting in that two pipe class dropouts are parallel in the casing, and the two pipe class dropouts will respectively adhere to the inner wall on the radial two sides of the casing. When using the fishing spear to fish the fish in this case, the spear rod of the fishing spear needs to be accurately positioned to adhere to the fish head of the pipe class dropouts on the inner wall of the casing.

[0003] The utility model with publication number CN202417378U discloses an oilfield fishing tool, mainly by drill rod joint, cylinder and spear rod are formed, the upper part of cylinder is connected drill rod joint, the eccentric position of lower part is connected spear rod. When using this kind of fishing tool to fish, although the spear rod is connected on the eccentric position of the cylinder, so that the spear rod can be aligned to adhere to the fish head of the pipe class dropouts on the inner wall of the casing after falling into the casing. But since the spear rod of the oilfield fishing tool is connected on the eccentric position of the cylinder, and the drill rod joint is coaxially connected with the cylinder, resulting in that the spear rod is not coaxial with the drill rod joint. Therefore, after the fish is successfully fished, since the weight of the fish is large, the fishing tool with the fish will inevitably produce eccentric swing in the wellbore, which is easy to form scratch and clamping in the well wall, resulting in failure of lifting. SUMMARY

[0004] The utility model provides a kind of fishing spear, to accurately fish the fish adhering to the inner wall of casing, and successfully lift it to well.

[0005] The utility model provides a kind of fishing spear, for fishing fish from the casing of oil well, comprising: drill rod joint;Spear rod, coaxially connected below drill rod joint;And, eccentric positioning piece, including the outer peripheral portion in its outer periphery in radial direction, spear rod is connected in outer peripheral portion and extends along the axial direction of eccentric positioning piece;The axis of spear rod is spaced apart from the axis of eccentric positioning piece by first preset distance;When fishing spear is explored to casing, the outer wall of eccentric positioning piece and the inner wall of casing are gap matched in the radial direction of casing, to limit the position of spear rod in casing in the radial direction of casing.

[0006] In one embodiment, the outer peripheral portion includes a body in a tubular structure;The spear rod extends along the axial direction of the body and is fixedly connected to the inner wall of the body;The axis of the spear rod is spaced apart from the axis of the body by the first preset distance.

[0007] In an embodiment, the eccentric positioning member further comprises: an upper baffle fixedly connected to the top of the body, the lance rod penetrating through the upper baffle and fixedly connected thereto; and / or, a lower baffle fixedly connected to the bottom of the body, the lance rod penetrating through the lower baffle and fixedly connected thereto.

[0008] In an embodiment, the upper baffle is provided with a first through hole penetrating through the body in the axial direction; and / or, the lower baffle comprises a second through hole penetrating through the body in the axial direction; the first through hole and the second through hole are both in communication with the interior of the body, and the first through hole and the second through hole are both located at the outer periphery of the lance rod.

[0009] In an embodiment, the lower baffle is connected to the extended middle part of the lance rod, and the lower baffle is spaced apart from the bottom of the lance rod by a second preset distance; when the lance is lowered into the casing, the lower baffle is limitedly matched with the fish on top of the fish in the casing, so that the bottom of the lance rod is suspended below the top of the fish on top of the fish by the second preset distance.

[0010] In an embodiment, the lance rod is provided with a water eye penetrating through the axial direction thereof, the water eye being in communication with the drill pipe joint, so as to flush the fish in the casing.

[0011] In an embodiment, the water eye is concentrically arranged with the lance rod.

[0012] In an embodiment, the lance further comprises a sliding block, one side of the sliding block being provided with a dovetail groove; the outer wall of the lance rod is provided with a dovetail guide rail inclined downward and away from the axis of the lance rod, the dovetail guide rail being located below the eccentric positioning member; the dovetail guide rail and the dovetail groove are in sliding cooperation; after the lance rod is inserted into the fish head inner cavity of the fish, the sliding block is slid downward into the fish head inner cavity; when the lance is lifted, the sliding block is slid downward relative to the lance rod and clamped by the fish and the lance rod.

[0013] In an embodiment, the bottom of the dovetail guide rail is provided with a blocking limiting member, the blocking limiting member blocking the sliding block in the downward direction, and the blocking limiting member being detachably connected with the lance rod.

[0014] In an embodiment, the sliding block comprises a protruding structure arranged on the side of the sliding block away from the lance rod, so as to increase the frictional resistance between the sliding block and the fish.

[0015] Compared with the prior art, the advantages of the utility model lie in when two pipe falling objects fall into the oil well casing simultaneously, the two pipe falling objects are extruded in the radial direction of the casing to adhere to the two sides of the inner wall of the casing respectively, after the fishing spear probes into the inside of the casing, based on the gap cooperation characteristics between the eccentric positioning member and the casing, the fishing spear can only move a small distance in the radial direction of the casing, the spear rod arranged on the outer circumferential part of the eccentric positioning member is positioned near the position of the first preset distance from the axis of the casing, therefore, the first preset distance can be configured appropriately according to the outer diameter of the pipe falling object and the inner diameter of the casing, so as to ensure that the spear rod is inserted into the pipe falling object adhering to the inner wall of the casing, when the spear rod captures the fish, the drill pipe can be lifted to take the fish out of the wellbore. When the fishing spear captures the fish with large weight, if the fish is eccentric with the drill pipe joint, the fish will form a certain yaw relative to the drill pipe, which causes the fish to form a scraping card with the inner wall of the casing, aiming at this situation, the spear rod of the utility model is coaxially connected with the drill pipe joint, therefore, when the fishing spear captures the fish, the pipe falling object, the spear rod and the drill pipe joint are coaxially connected in sequence, after the three are coaxially connected, the fish will not yaw relative to the drill pipe to the radial side of the casing, which avoids the fish to form a scraping card with the inner wall of the wellbore, and ensures that the fish is lifted to the well smoothly. BRIEF DESCRIPTION OF DRAWINGS

[0016] The utility model will be described in more detail below based on the embodiments and with reference to the drawings.

[0017] Figure 1 is the axial sectional view of the fishing spear in the embodiment of the utility model.

[0018] FIGURE

[0019] 1, drill pipe joint; 2, spear rod; 21, inclined plane; 22, guide part; 211, dovetail guide rail; 3, sliding block; 31, make buckle thread; 4, stop key; 5, pin; 6, water eye; 7, eccentric positioning member; 71, main body; 72, upper baffle; 73, lower baffle; 8, through hole. DETAILED DESCRIPTION

[0020] The utility model will be described in more detail below based on the embodiments and with reference to the drawings.

[0021] Refer to Figure 1 , the embodiment provides a kind of fishing spear, it include: drill pipe joint 1, spear rod 2, sliding block 3 and eccentric positioning member 7.Wherein, the upper portion of drill pipe joint 1 is processed with the female buckle connected with drilling tool, the lower portion of drill pipe joint 1 is processed with the female buckle connected with spear rod 2.Spear rod 2 top is processed with the male buckle connected with drill pipe joint 1, and drill pipe joint 1 and spear rod 2 are connected by male buckle female buckle cooperation.

[0022] The lower part of the lance 2 comprises an inclined surface 21 inclined to the axis of the lance 2, the inclined surface 21 is inclined in the downward direction and away from the axis of the lance 2; the sliding block 3 is slidingly installed on the inclined surface 21; when the sliding block 3 slides upward on the inclined surface 21, the sliding block 3 is close to the axis of the lance 2. A water hole 6 is formed in the center of the lance 2 and extends through the axial direction of the lance 2, the water hole 6 is communicated with the drill pipe joint 1, and the water hole 6 can be circulated to flush the fish head. The bottom of the lance 2 is provided with a tapered guide part 22 to facilitate the lance 2 to be inserted into the fish cavity of the fallen fish. Further, the inclined surface 21 is located above the guide part 22 and below the lower baffle 73; the inclined surface 21 is provided with a dovetail guide rail 211, one side of the sliding block 3 is processed with a dovetail groove, the dovetail guide rail 211 and the dovetail groove are slidingly matched, and the distance between the sliding block 3 and the center line of the lance 2 is reduced or increased. The bottom of the dovetail guide rail 211 is provided with a stop key 4, the stop key 4 is matched with the lance 2 through the pin 5 penetrating into the stop key 4 and the threaded connection of the lance 2, so that the stop key 4 and the lance 2 are fixed together, the stop key 4 limits the downward position of the sliding block 3, and after the stop key 4 and the pin 5 are removed, the sliding block 3 can be slid out of the dovetail guide rail 211 to replace the sliding block 3 of different models. The stop key 4 is a blocking and positioning member of the utility model.

[0023] The eccentric positioning member 7 comprises a body 71 in a tubular structure, and an upper baffle 72 and a lower baffle 73 fixedly connected to the upper and lower ends of the body 71. The lance 2 extends along the axial direction of the body 71 and is fixedly connected to the inner wall on one side of the body 71 in the radial direction, and the lance 2 maintains a certain distance from the inner wall on the other side of the body 71 in the radial direction, at this time, the axis of the lance 2 is located at a first preset distance on one side of the axis of the body 71; since the outer diameter of the body 71 is slightly smaller than the inner diameter of the sleeve, when the lance is put into the well, there is only a small distance between the outer wall of the body 71 and the inner wall of the sleeve, and the two are in clearance fit, the body 71 can only move a small distance in the radial direction of the sleeve in the sleeve, so that no matter how the body 71 moves in the radial direction of the sleeve, it will soon be limited by the sleeve, so as to realize the positioning of the lance 2 in the sleeve; further, since the axis of the eccentric positioning member 7 is close to the axis of the sleeve, the lance 2 located at the first preset distance on one side of the axis of the eccentric positioning member 7 can only be at a position close to the first preset distance from the axis of the sleeve, and after the appropriate first preset distance is determined through calculation, it can be ensured that the axis of the lance 2 is located above the fish head inner cavity of the pipe-shaped fallen object abutting against the inner wall of the sleeve. Further, the lance 2 is located on the inner wall on one side of the body 71 and away from the inner wall on the other side of the body 71, and also close to the inner wall on one side of the sleeve and away from the inner wall on the other side of the sleeve, so that the setting of the eccentric positioning member 7 forces the lance 2 to be located above the fish head inner cavity of the pipe-shaped fallen object abutting against the inner wall of the sleeve, so that the lance 2 can be inserted into the fish head inner cavity.

[0024] Further, the body 71 of the tubular structure realizes the light weight of the eccentric positioning member 7, and reduces the influence of the eccentric positioning member 7 on the eccentricity of the spear 2 as much as possible; the spear 2 penetrates the upper baffle 72 and the lower baffle 73 in turn and is fixedly connected with the two baffles, and the arrangement of the upper baffle 72 and the lower baffle 73 improves the connection strength between the body 71 and the spear 2. The upper baffle 72 and the lower baffle 73 are each provided with a through hole 8 penetrating the axial direction thereof, the through hole 8 is located at the outer periphery of the spear 2, the two through holes 8 are oppositely arranged and are both in communication with the inside of the body 71, the circulation channel of the fluid in the well is increased, and the pumping pressure and the surge pressure in the tripping process can be effectively reduced. The through hole 8 on the upper baffle 72 is the first through hole of the utility model, and the through hole 8 on the lower baffle 73 is the second through hole of the utility model. The body 71 is the outer peripheral part of the utility model. Of course, in some embodiments, the outer peripheral part can also be the annular part located at the outer periphery of the upper baffle 72 and the lower baffle 73.

[0025] Further, in some cases, two tubular dropouts fall into the casing in turn, the tubular dropout falling later cannot pass through the space between the fish head (the coupling) of the tubular dropout falling earlier and the casing due to the larger diameter of the coupling, the lower end of the coupling of the tubular dropout falling later is hung and clamped on the upper end face of the coupling of the tubular dropout falling earlier, the two fish heads only differ by one height of the coupling, and the two tubular dropouts are pressed in the radial direction and are respectively biased to the two sides of the inner wall of the casing with one high and one low. At this time, if the spear is first inserted into the fish head inner cavity of the tubular dropout falling lower among the two tubular dropouts with one high and one low, the tubular dropout falling higher will limit the tubular dropout being lifted in the upward direction, and the two tubular dropouts will be pressed and locked in the sleeve, resulting in fishing failure. In view of this situation, the lower baffle 73 is arranged at a position which is less than one height of the coupling from the bottom of the anchor rod; after the fishing spear is lowered into the well, the lower baffle 73 is limited and matched with the tubular dropout falling higher among the two tubular dropouts with one high and one low, and since the length of the spear 2 below the lower baffle 73 is less than one height of the coupling, the spear 2 can be prevented from being mistakenly inserted into the fish head inner cavity of the tubular dropout falling lower among the two tubular dropouts with one high and one low. The second preset distance is less than or equal to one height of the coupling.

[0026] In some embodiments, a plurality of through holes 8 are respectively formed in the upper baffle 72 and the lower baffle 73.

[0027] Further, the side of the sliding block 3 away from the spear 2 is provided with an arc surface matched with the inner wall of the fish cavity, the arc surface protrudes away from the axis of the spear 2, and a thread forming screw 31 is formed on the protruding arc surface, which can bite the inner wall of the fallen fish during fishing construction.

[0028] In some embodiments, the thread forming screw 31 can be replaced by a rough surface or a plurality of protruding structures such as point-shaped protrusions and strip-shaped protrusions.

[0029] During fishing operation, the fishing spear in the embodiment is connected with the fishing tool and lowered to 0.5-1m above the fish top, the pump is started to circulate and flush the sand accumulated in the fish cavity, after the fishing spear in the embodiment is lowered to the working position, the fishing is tried by rotating 45° each time within 360° of the tool fastening direction, the lower end of the baffle 73 contacts the fish top of the fish in the high position, so that the spear rod 2 cannot continue to descend, and the spear rod 2 cannot be inserted into the inner cavity of the fish head of the fish in the low position; when the spear rod 2 is inserted into the deep part of the inner cavity of the fish head of the fish in the high position, the sliding block 3 slides into the inner cavity of the fish head by relying on its own gravity, until the thread 31 of the sliding block 3 contacts the inner wall of the pipe column, at this time, the spear rod 2 is lifted, the spear rod 2 moves upward relative to the sliding block 3 and the fish and generates a radial force to force the thread 31 of the sliding block 3 to bite into and tightly hold the fish, so as to fish out the fish.

[0030] In some embodiments, the fishing can also be tried by lowering every 15° or 30° of rotation and other angles

[0031] In summary, the fishing spear of the utility model is reliable in work, simple in manufacturing, effectively solves the problem that fishing of overlapped fallen objects easily causes more complex downhole failure, greatly improves the fishing effect, reduces the workover cost, and has good popularization value.

[0032] Although the utility model has been described with reference to the preferred embodiments, various improvements can be made and equivalent parts can be replaced without departing from the scope of the utility model. In particular, each of the technical features mentioned in each of the embodiments can be combined in any way as long as there is no structural conflict. The utility model is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A spear for fishing fish from within a casing of an oil well, characterized in that, The utility model relates to a fishing spear, which comprises a drill rod joint, a lance coaxially connected below the drill rod joint, and an eccentric positioning member comprising an outer peripheral portion radially located at the outer periphery of the eccentric positioning member, the lance being connected to the outer peripheral portion and extending along the axial direction of the eccentric positioning member, the axis of the lance being spaced apart from the axis of the eccentric positioning member by a first preset distance. When the fishing spear is lowered into the casing, the outer wall of the eccentric positioning member is in clearance fit with the inner wall of the casing in the radial direction of the casing to limit the position of the lance in the casing in the radial direction of the casing. The outer peripheral portion comprises a body in a tubular structure, the lance extending along the axial direction of the body and being fixedly connected to the inner wall of the body, the axis of the lance being spaced apart from the axis of the body by the first preset distance. The eccentric positioning member further comprises an upper baffle fixedly connected to the top of the body, the lance penetrating through the upper baffle and being fixedly connected thereto, and / or a lower baffle fixedly connected to the bottom of the body, the lance penetrating through the lower baffle and being fixedly connected thereto. The upper baffle is provided with a first through hole penetrating through the body along the axial direction, and / or the lower baffle is provided with a second through hole penetrating through the body along the axial direction. The first through hole and the second through hole are both in communication with the inside of the body, and the first through hole and the second through hole are both located at the outer periphery of the lance.

2. The fishing spear according to claim 1, wherein the lower baffle is connected to the extended middle portion of the lance, and the lower baffle is spaced apart from the bottom of the lance by a second preset distance; when the fishing spear is lowered into the casing, the lower baffle is in limiting fit with the fish with the highest fish top among the plurality of fish in the casing to make the bottom of the lance suspended at a second preset distance below the top of the fish with the highest fish top. The lance is provided with a water eye penetrating through the axial direction of the lance, the water eye being in communication with the drill rod joint to flush the fish in the casing. The water eye is concentrically arranged with the lance.

5. The fishing spear according to claim 1 or 2, wherein the fishing spear further comprises a sliding block, one side of the sliding block being provided with a dovetail groove; the outer wall of the lance is provided with a dovetail guide rail inclined downward and away from the axis of the lance, the dovetail guide rail being located below the eccentric positioning member; the dovetail guide rail is in sliding fit with the dovetail groove; after the lance is inserted into the fish head inner cavity of the fish, the sliding block is slid downward into the fish head inner cavity; the fishing spear is lifted up, and the sliding block is slid downward relative to the lance and clamped by the fish and the lance. The bottom of the dovetail guide rail is provided with a blocking limiting member, the blocking limiting member blocking the sliding block in the downward direction, and the blocking limiting member is detachably connected with the lance. The sliding block comprises a protruding structure arranged on the side of the sliding block away from the lance to increase the frictional resistance between the sliding block and the fish. ​ ​ ​ 3. A spear as claimed in claim 1 or 2, characterized in that ​ 4. The spear of claim 3, wherein, ​ ​ ​ ​ ​ 6. The spear of claim 5, wherein, ​ 7. The spear of claim 5, wherein, ​

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