Rope coring fishing system for deep sea subsea drilling rig and method of use thereof

Abstract

The invention discloses a deep-sea submarine drilling rig rope coring salvage system and its use method. The deep-sea submarine drilling rig rope coring salvage system includes a salvage winch, a salvage rope, an underwater pull force sensor, a top cover, a main shaft and a salvage device; a salvage rope One end is wound on the salvage winch, and the other end of the salvage rope goes around the pulley at the lower end of the underwater pull force sensor, passes through the tapered hole on the top cover and is connected with the upper end of the overshot placed in the central hole of the main shaft. The present invention utilizes the self-weight of the heavy hammer rod of the dredge to provide the driving force, and through the cooperative work among the helical teeth of the pressing rod, the helical teeth of the rotating core, the helical teeth of the rotating core II and the compression spring, not only can the spearhead be fished out of the inner tube of the rock core It can also be locked by driving the rotary core ferrule to rotate an angle of the rotary core helical tooth Ⅰ or rotary core helical tooth Ⅱ to release the clamping of the spear head of the inner tube of the core, so that the inner tube of the core can be realized very conveniently. fishing and release; and the present invention can also easily solve the problem of pipe sticking in the inner pipe of the core.

Description

technical field [0001] The invention relates to a rope coring fishing system for a deep-sea submarine drilling rig and an application method thereof. Background technique [0002] Wireline coring technology has become an important development direction of land and seabed drilling rig coring technology because of its advantages such as short auxiliary operation time, high operation efficiency, good wall protection effect, and high core quality. The key device of the wireline coring technology is the wireline core drilling tool, which is mainly composed of two parts: the outer tube of the core drilling tool and the inner core tube placed inside the outer tube of the core drilling tool. After the second core drilling, it is necessary to drive the salvage winch to lower the overshot to salvage the inner tube of the core. [0003] Patent CN109826579A discloses a cable coring fishing system and method for a submarine drilling rig. Before releasing the core pipe, the cable coring ...

AI Technical Summary

Problems solved by technology

However, during the drilling process of the subsea drilling rig, due to reasons such as improper drilling technology or failure of the flushing fluid circulation system, the drill burnt out, which in turn causes the core tube to be stuck inside the outer tube of the core drilling tool. At this time, using this The rope coring and fishing system salvages the core pipe. After the fishing hook of the overhaul hooks the spearhead on the top of the core pipe, if the winch is driven to take up the cable, the overshot and the core pipe cannot be recovered. In this state, the hook cannot be unhooked, and all the drill pipes and the outer tube of the core drilling tool cannot be recovered. If the overshot is continued to be recovered forcibly, the fishing rope will be broken, which will lead to the failure of the entire coring work at this station.

[0004] Patent CN104453765B discloses an overshot of a rope core drilling tool, the overshot of the rope core drilling tool is provided with a valve shaft, a mud flow channel and a mud discharge hole connected to the flow channel, and the overshot is driven by the mud work, so as to realize the salvage of the spearhead by the overhauler. The structure of the overshot is relatively complicated, and other auxiliary devices (mud pumps) are needed to complete the salvage operation of the inner tube of the core. Not only the cost of the salvage operation is high, but also during the salvage process It is very likely that some mud will be left inside the drill tool or at the bottom of the drill bit, so that the mud will be cored into the core tube during the next coring operation, which will cause the core sample to be "contaminated", which will lead to damage to the formation. Analysis is biased

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