Waterproof casing mounting method-immersed tube drilling method

Abstract

The invention relates to a water string installation method, namely, the immersed tube drilling method; a drill bit (2) is arranged at the lower end of a water string (1), the drill is connected with a power station (5) on a platform by a power hose bundle (8) in the water string (1), the water string (1) is hung on a large hook (3) of the platform drill and is lowered gradually, the rise and fall of the drilling tool and the power hose bundle (8) is realized by a cable winch (7) arranged on the platform and a hose winch (6), the drill bit (2) drills holes by the combination way of the mechanical drilling force and the water flushing force; the diameter of a drill hole (4) is greater than that of the water string (1), the water string (1) is inserted into the drill hole (4) together with the drill bit (2) until the design position is reached. The invention firstly proposes that the drill bit is arranged at the lower end of the water string and the well pipe is lowered during the drilling process, which avoids that the drill hole collapses and reduces the installation cost, and the invention is especially suitable for the addition of a small amount of new wells on the existing platform facility.

Description

technical field [0001] The invention belongs to the innovation of an offshore installation method of a water-resisting casing in offshore oil engineering. Background technique [0002] The work of lowering the riser belongs to the pre-drilling preparation work, the purpose is to isolate the sea water, control the direction of the drilling tool and provide a channel for the mud circulation to return to the platform. The traditional offshore installation methods of riser casing include driving method and drilling method. The driving method is that when the fixed platform is drilling wells, after the jacket is installed and fixed, the well location is designed according to the cluster well, and the water-resisting casing is driven into the well location one by one by the pile driver, and the driving depth is not less than 40m. The drilling method is to use drilling equipment on a floating or movable drilling platform to drill the wellbore first, then run the water-resistant ca...

AI Technical Summary

Problems solved by technology

For the situation of adding a small number of wells to the existing platform facilities, the traditional riser casing installation method is particularly uneconomical. More importantly, both the drilling method and the driving method have inherent defects. The defect of the driving method is that it causes The platform vibrates, affecting normal production; the defect of the drilling method is the problem of well wall collapse

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