RU2268987C1 - Collet tool - Google Patents

Abstract

FIELD: oil production industry, particularly for fishing or freeing objects in boreholes or wells.

SUBSTANCE: collet tool comprises collet with at least two opened leafs and tail, thrust case installed from collet outside and shaft with shear pin arranged inside the collet. The shaft has end of variable cross-section to provide movement and smooth opening of collet leafs. The thrust case has lower guiding means and slip is installed in the thrust case. The collet is provided with outer buttress thread formed on the tail and arranged under the slip. The buttress thread is adapted to regulate and limit collet stroke. Collet leafs have locking supporting collar arranged from inside and with thrust collar formed from outside thereof. Core with locking outer thrust collar is located inside the collet. The collar is put on the shaft and fixed from above by the shear pin. Shaft and/or core comprises fishing heads of lesser and larger diameters correspondingly and/or the collar has upper outer pipe or shaft thread. If the tool is installed in its initial position collet tail is fixed relative the core by shear pins and collet leafs may be pressed one to another to reduce diameter thereof during object fishing. If the tool is installed in its working position after object fixation by the tool for shear screws shearing by applying impact in top-down direction the core with shaft tail may slide into the collet and collet leafs may be opened as shaft tail moves inside the collet as outer thrust core collar is closed up with supporting collar of the collet to provide rigid fixation of initial or extended diameters thereof. If the tool is installed in tool releasing position after shear pin shearing by applying impact in down-top direction during object fishing the collet may be opened and the leaf diameter may be increased as the shaft tail moves through the leafs in return direction, wherein the core is released from locking supporting collar of the collet leafs to provide following pressing thereof during tool removing from the object.

EFFECT: increased efficiency and extended functional capabilities.

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Description

The invention relates to oil and gas production techniques and can be used for catching and retrieving nodes, elements and devices (for example, a guiding element above the barrel of a column disconnector and / or packer, a downhole tool, an emergency element, etc.) from a well.

Known lifting tool type IC (Reference manual on the gas-lift method of operating wells. Yu. Zaitsev, R.A. Maksutov, O.V. Chubanov and others - M .: Nedra, 1984, see page 131), including the casing, adapter, stem, collet, shear pin, stopper and locking screw.

Also known is a lifting tool of the IPZ type (Reference manual on the gas-lift method of operating wells. Yu. Zaitsev, R.A. Maksutov, O.V. Chubanov and others - M .: Nedra, 1984, see page 131), including the case , head, rod, collet, shear pin, spring and holder. This tool is less effective for catching from the inside various nodes and elements in the well, since it does not have the ability to control the working stroke of its collet depending on the size of the internal grooves of the nodes and elements.

A well-known universal downhole tool (RF patent No. 21114978, 6 E 21 B 23/00, 31/18, July 10, 1998), comprising a housing, inside which a spring-loaded rod is installed, connected to it through a shear pin, and outside - a spring-loaded collet with petals. This tool is unacceptable for inside fishing nodes and elements for their extraction from the well.

The aim of the invention is to increase efficiency while expanding the functionality of the tool.

The positive effect of the use of the invention is to increase the efficiency of the tool and reduce the time it takes to carry out the operation "descent-rise" of the tool in the well.

The purpose of the invention is achieved in that the collet tool is provided with a thrust housing mounted outside the collet. The rod is made with a tip of variable cross-section for moving and smooth opening of the collet petals. The thrust casing is made with a lower guide and a slip is placed inside it, under which the collet on top of the shank is made with an external thrust for regulating and fixing its working stroke. The collet petals are made inside with a locking support collar, and outside with a persistent collar. Inside the collet there is a core with a lock outer thrust collar, mounted on the rod and fixed with it from above through a shear pin with the possibility of cutting it upside down when the tool is released. The rod and / or core have a fishing head, respectively, of a larger or smaller diameter, and / or the core is made from the top with an external pipe or rod thread. In the initial position of the tool, the collet shank is fixed relative to the core with shear screws and the collet petals are able to be pressed and reduce their diameter when catching a node or element. When the tool is in the working position, after catching the knot or element and cutting the shear screws with the blow down, on the contrary, the collet is made with the possibility of moving the core in it with the tip of the rod down and opening its petals when passing through the tip of the rod and closing the outer thrust collar of the core with supporting collar of the collet petals for rigid fixation of the initial or increased diameter. In the position of releasing the tool, after cutting the shear pin with an upward impact in the state of catching a node or element, the collet is made with the possibility of opening and increasing the diameter of its petals when the tip of the rod passes back through them and the core is released from the locking support collar of the petals of the collet to allow further pressing at the time of removal of the tool from the node or element.

Figure 1 shows a General view of the tool in its original position; figure 2 - the tool in its original position in the guide element; figure 3 - the tool in the working position (fixation) in the guide element; figure 4 - the tool is in the released position from the guide nipple.

The tool (Figs. 1-4) includes a collet 1 with a shank 2 and open petals 3 (there may be two or more), a thrust casing 4 installed outside the collet 1, and a rod 5 with a shear pin 6 inside it. In this case, the rod 5 is made with a tip 7 of variable cross-section for moving and smoothly opening the petals 3 of the collet 1. The thrust casing 4 can be made with the lower guide 8 and inside it there is a slot 9 under which the collet 1 has an external stop thread 10 on top of the shank 2 for adjusting and fixing it working stroke. The petals 3 of the collet 1 are made inside with a locking support collar 11, and on the outside with a locking collar 12. Inside the collet 1 there is a core 13 with a locking external contact collar 14, mounted on the rod 5 and fixed on top with the rod 5 through a shear pin 6. Rod 5 and / or the core 13 may have a fishing head 15 and 16, respectively, of a larger or smaller diameter for the fishing tool, and / or the core 13 from above can be made with an external pipe or rod thread 17.

The tool works as follows.

The collet tool is lowered into the well in its original position (see figure 1). To do this, the shank 2 of the collet 1 is fixed relative to the core 13 with shear screws 18, and then the tool is lowered into the well 19 using cable technology either on the rod or on the pipe. When you enter the collet 1 (see figure 2) in the node or element 20 (for example, in a removable guide node above the rod or above the barrel 21 of the pipe string disconnector with a packer, etc.) its lobes 3 are pressed and go into the groove of the node or element 20. And then the working position of the tool is ensured (see Fig. 3) by cutting off its shear screws 18 (for example, by mechanical impact down using a cable technique or due to the axial load of the column rod or pipes). Here, the core 13 with the tip 7 of the rod 5 moves downward inside the collet 1 and opens its petals 3 while passing through the tip 7 of the rod 5. This closes the external thrust collar 14 of the core 13 with the supporting collar 11 of the petals 3 of the collet 1, thereby providing a rigid fixation the initial or increased diameter of the petals 3 in the groove of the node or element 20 for its extraction from the well.

The release of the tool (see Fig. 4) is provided by cutting its shear pin 6 with an upward stroke of the rod 5 in the state of catching the nodes or elements 20. In this case, the collet 1 opens and the diameter of its petals 3 increases when the tip 7 of the rod 5 passes back through them, the core 13 is thereby freed from the locking support collar 11 of the petals 3 of the collet 1 so that they can be pressed at the moment the tool is removed from the assembly or element 20.

Claims (1)

A collet tool, including a collet with at least two open petals and a shank, a rod with a shear pin mounted inside the collet, characterized in that the collet tool is equipped with a thrust housing mounted on the outside of the collet, the rod is made with a tip of variable cross section for moving and smooth opening of the petals collet, thrust casing is made with a lower guide and a slip is placed inside it, under which the collet on top of the shank is made with an external threaded thread for adjusting and fixing its work about the course, while the collet petals are made inside with a locking support collar, and outside with a locking collar, inside the collet there is a core with a locking external contact collar, mounted on the rod and fixed with it from above through a shear pin with the possibility of cutting it upward with impact the release of the tool, while the rod and / or core have a fishing head, respectively, of a larger or smaller diameter, and / or the core on top is made with an external pipe or rod thread, and with the initial position of the tool the collet shank is fixed relative to the core by shear screws and the collet petals are able to press and reduce their diameter when catching a knot or element, and when the tool is in working position after catching a knot or element and shear shears are cut downward, the collet is movable core with the tip of the rod down and the opening of its petals when passing through the tip of the rod and shorting the external thrust collar of the core with the supporting collar of the petals of the collet for iron by fixing the initial or enlarged diameter thereof, and when the tool is released after cutting the shear pin with an upward strike in the state of catching a node or collet element, it is possible to open and increase the diameter of its petals when the tip of the rod passes back through them and the core is released from the locking support collar of collet petals for the possibility of further pressing them at the time of extraction of the tool from the node or element.

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