Liquid-gas control system for controlled-pressure drilling equipment

Abstract

The invention discloses a liquid-gas control system for controlled-pressure drilling equipment, relates to the technical field of drilling equipment, and aims to solve the problems of inaccuracy in controlling the annular pressure of a well in the conventional drilling process. The liquid-gas control system for the controlled-pressure drilling equipment provided by the invention comprises a power source, and a throttling valve control component, a hydraulic control flat plate gate valve control component, a pneumatic control flat plate gate valve control component and an oil return pump system pneumatic control flat plate gate valve control component which are connected with the power source. Accurate control of the annular pressure of the well is realized in a combination way of pneumatic control and hydraulic control. Moreover, one branch of compressed gas is connected to an oil outlet pipeline of an oil storage device through a liquid-gas pump, so that the outlet pressure of liquid can be effectively raised.

Description

technical field [0001] The invention relates to the technical field of drilling equipment, in particular to a liquid-gas control system for pressure-managed drilling equipment. Background technique [0002] During the drilling of oil and gas wells, if the formation pore pressure is greater than the pressure of the drilling fluid in the wellbore annulus, the formation fluid will flow into the wellbore. Damage to personnel and equipment. The traditional drilling method uses a high-density drilling fluid system to keep the wellbore hydrostatic column pressure greater than the formation pore pressure even when the drilling fluid stops circulating. However, when the formation pore pressure-fracture pressure window is narrow, drilling begins The pressure generated after the fluid circulation may exceed the fracture pressure of the formation, resulting in the collapse of the well wall, and under the action of the pressure difference, the drilling fluid will enter the formation and...

AI Technical Summary

Problems solved by technology

[0004] Pressure control drilling equipment is used in harsh environments, for example: there may be flammable gas escaping from the downhole, the wellhead pressure may be high, due to the start-up and shutdown of the mud pump, and the movement of the drilling tool, the bottom-hole pressure may fluctuate rapidly due to different well types and drilling fluids. Larger, making pressure control difficult

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