Method and device for machining inner blind hole of perforating gun for oil-gas well

Abstract

The invention relates to a method and a device for machining an inner blind hole of a perforating gun for an oil-gas well, which solve the problems of rotation instability and the like caused by long-distance power transmission required in the past. The device for machining the inner blind hole of the perforating gun for the oil-gas well, provided by the invention, comprises: (1) a drilling tool assembly and a supporting device, which are arranged on a cutter connecting rod; and (2) a vertical milling machine. During machining, a gun body of the perforating gun is assembled and clamped on a workbench of the vertical milling machine and is moved by using workbench of the vertical milling machine so as to extend the drilling tool assembly and the supporting device into the gun body of the perforating gun and make a drillbit of the drilling tool assembly located at a position at which the inner blind hole is machined; and then, an inner expansion mechanism of the supporting device is utilized to tightly lock a cutter rod and the gun body of the perforating gun to form firm support, a power transmission rod of the vertical milling machine penetrates through a pressure relief hole in the gun body of the perforating gun and is connected with the drillbit of the drilling tool assembly in an engagement manner; and the power transmission rod drives the drillbit of the drilling tool assembly to rotate and realize drilling feeding until the inner blind hole is machined completely.

Description

technical field [0001] The invention belongs to the field of mechanical processing, and in particular relates to a processing method and device for blind holes in perforating guns used in oil and gas wells. Background technique [0002] At present, perforating guns for oil and gas wells widely adopt the method of processing outer blind holes or no blind holes on the outer wall of the gun body, which makes the blast height of the deep penetrating perforating charge in the gun body too low, far less than the ideal blast height, resulting in The energy-gathering jet produced after the detonation of the perforating bullet encounters obstacles prematurely, and the energy-gathering effect and energy of the perforating bullet are not fully exerted, thereby reducing the penetration depth of the perforator. According to the detonation theory of perforating charges, when the blasting height of perforating charges is lower than the ideal blasting height, increasing the blasting height ...

AI Technical Summary

Problems solved by technology

Existing known method mainly adopts two kinds of methods in processing the inner blind hole in the inner wall of the gun body: (1) drill a step through hole in the outer wall of the gun body, then select the same material to make sheet or gland, and use welding or press-in process Block the step hole part, resulting in the inner blind hole

(2) A super-long rod is designed, and the cutting power is transmitted from one end of the super-long rod to the tool fixed on the other end of the super-long rod by means of a gear set or a sprocket group, and then the inner blind hole is realized through the movement of the gun body Cutting feed movement; this method has the following three defects: (1) No matter whether the gear set or the sprocket set is adopted to realize the power transmission of the ultra-long rod, there is inevitably a serious power loss, resulting in an increase in power cost; ( 2) The sprocket drive cannot realize continuous transmission in the true sense, resulting in unstable and discontinuous rotation of the tool, which affects the quality of inner blind hole processing; at the same time, frequent damage and replacement of the gear set or sprocket set components due to unstable transmission, resulting in The use efficiency of the device is reduced; (3) Restricted by the inner diameter of the perforating gun, the diameter of the super-long rod is too small compared with the length. There is a large difference between the given depth and the actual processing depth, which seriously affects the quality of inner blind hole processing

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