Downhole high pressure and large flow uncontrolled hydrological drilling plugging system and method

Abstract

The invention provides a system and method for downhole high-pressure, large-flow out-of-control hydrological drilling plugging. In the damaged hydrological drilling casing, a new casing of one level smaller is re-runned, and then a casing of an appropriate size is run in according to the gap between the old and new casings. Hard aggregate and soft aggregate (the specific gravity is smaller than water), inject a certain amount of soft and hard aggregate into the new casing in a certain proportion, and use the principle that water always flows along the direction of the least resistance. Under the action of pressurized water and the pump pressure above, it can only enter the gap between the new and old casings with low resistance. The hard aggregate fills the large gap between the new and old casings to act as a skeleton and support, and the soft aggregate fills the hard bone. The material gap, and then inject cement through the new casing to complete the treatment. The soft and hard aggregates are skillfully combined, which has both strength and flexibility, and a small specific gravity. The hard aggregates are mainly pine wood blocks and wooden wedges, and the soft aggregates are sawdust, Wood shavings are mainly used to solve the problem of high pressure and large flow damage hydrological drilling.

Description

technical field [0001] The invention relates to the technical field of coal mine water disaster prevention and control, in particular to a plugging method for out-of-control water discharge from hydrological borehole damage in underground coal mines. Background technique [0002] A large number of hydrological drilling holes were constructed during the exploration and production of coal mines. Especially after decades of mining, most coal mines are in deep mining. Some hydrological drilling holes are due to changes in the stress of the roadway surrounding rock and the bottom of the drilling hole. Due to the influence of various factors and reasons such as the structure and long construction time, some hydrological drilling casings are broken or damaged, which makes the drilling gate valve out of control, making the aquifer water run out from the bottom plate around the drilling, causing water damage accidents, due to the damage of the drilling The situation is complex and of...

AI Technical Summary

Problems solved by technology

This type of method can be used for water drilling with low water pressure and water volume, but it still has the characteristics of failure of treatment once the capsule and rubber plug are damaged, and it takes a long time to process and the risk is high.

As for the treatment of hydrological boreholes damaged by high water pressure and large flow rate, the traditional capsule, rubber plug and soft aggregate treatment method, due to high water pressure and high flow rate, will result in poor effect of soft aggregate material, long time or even failure, resulting in water damage accidents. Therefore, research A simple and easy method for rapid plugging of complex hydrological drilling under high pressure, large flow, out-of-control damage in the hole, and dynamic water conditions is a water disaster prevention and control technical problem that needs to be solved in coal mine production at present.

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