Well drilling device and method for controlling bottom hole pressure by monitoring flow

Abstract

The invention discloses a well drilling device and method for controlling bottom hole pressure by monitoring flow. The well drilling device comprises a slime pump inlet flow measuring system, a return pressure pump inlet flow measuring system, a drilling liquid reversing-out flow measuring system, an automatic throttling pipe converging system, a rotation control head, a liquid-gas separator and a vibration screen. The inlet of the slime pump inlet flow measuring system is connected to a slime tank through a pipeline. The outlet of the slime pump inlet flow measuring system is connected to a drilling rod through a pipeline, reaches the rotation control head from a drill and a borehole by passing the bottom of the drilling rod in an annular space mode, and is communicated with an inlet pipeline of the automatic throttling pipe converging system and an outlet pipeline of the return pressure pump inlet flow measuring system. The return pressure inlet flow measuring system is connected to the slime tank through a pipeline. The outlet of the automatic throttling pipe converging system is connected with the inlet of the drilling liquid reversing-out flow measuring system. The outlet of the drilling liquid reversing-out flow measuring system is connected with the inlet of the liquid-gas separator through a pipeline. The liquid-gas separator is provided with two branches, wherein one branch is connected to the vibration screen and connected to the slime tank through the vibration screen and the other branch is connected to a combustion opening. The well drilling device and method for controlling the bottom hole pressure by monitoring the flow can effectively control or eliminate adverse affection on well drilling, wherein the adverse affection is caused by shaft bottom leakage and losses or overflowing which can cause.

Description

technical field [0001] The invention belongs to the field of oil and natural gas drilling pressure control systems, and relates to a drilling equipment and method for realizing bottom-hole pressure control by using flow monitoring. Background technique [0002] Loss and overflow are downhole complex situations that are often encountered in the drilling process. Among them, leakage refers to a downhole complex situation in which drilling fluid leaks into the formation during oil and gas drilling engineering operations. On the one hand, it directly leads to the loss of a large amount of drilling fluid and affects normal drilling. During operation, the well wall may even become unstable due to the excessive drop in fluid column pressure, leading to well collapse or even sticking, and the scrapping of some or all well sections. It will cause serious damage to the reservoir; and overflow refers to a complex downhole situation in which formation fluid flows into the wellbore durin...

AI Technical Summary

Problems solved by technology

However, wellhead overflow may be caused by uneven weighting of the drilling fluid; if the pressure of the standpipe drops, it may be a puncture of the drilling tool; caused by

Using traditional drilling methods, if leakage or overflow is found, the amount of leakage or overflow is already large, and there is no quick solution. For example, if a leakage occurs, it is necessary to prepare for plugging, and if an overflow occurs, it is necessary to shut down the well for pressure, and then circulate Exhaust, extremely low efficiency, and hidden safety hazards

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