Fixed point sealing method for gas extraction drilled hole

Abstract

The invention discloses a fixed point sealing method for a gas extraction drilled hole. The fixed point sealing method comprises the steps that firstly, the gas extraction hole with the diameter being 60-80 mm is constructed in a coal seam; a heat resistance wire and a heat expansion material are bound in the position of 1-2 m of the front end of a gas extraction pipe; the gas extraction pipe is sent to the interior of the drilled hole to enable the heat resistance wire and the heat expansion material to reach a preset position of drilled hole sealing; and a power supply heats the heat resistance wire through a wire, the heat resistance wire transfers heat to the heat expansion material, the temperature of the heat expansion material is increased, and electric heat expansion occurs, so that sealing of the gas extraction drilled hole is achieved. The process is simple, operation is convenient, fixed point and fixed time sealing of the gas extraction drilled hole can be achieved, the hole sealing success rate is increased, and the requirements of works of gas treatment and the like of a coal mine site area are met.

Description

technical field [0001] The invention relates to a fixed-point sealing method for gas drainage boreholes, which belongs to the technical field of gas control in the underground area of ​​coal mines, and is especially suitable for fixed-point sealing operations of large-diameter and long-distance gas drainage boreholes in deep coal seams. Background technique [0002] At present, the fundamental method to prevent and control coal mine gas disasters is to carry out gas drainage. The coal mine gas management policy of "draining first, then mining, monitoring and monitoring, and wind to determine production" determined by the State Administration of Work Safety also puts gas drainage in the first place. "Regulations on the Prevention and Control of Coal and Gas Outbursts" and "Basic Indicators for Gas Drainage in Coal Mine" (AQ1026-2006) also put forward clear requirements for gas drainage from the policy level. However, effective sealing of boreholes for gas drainage is the key...

AI Technical Summary

Problems solved by technology

At present, polyurethane, organic resin materials or cement-like sealing materials are commonly used in coal mines in my country. These materials are mixed with various chemical slurries by hand stirring. Since the interval between the beginning of mixing and foaming of chemical slurries is only tens of seconds (usually less than 30s), Therefore, usually the mixed slurry has begun to foam and expand during the advancement of the gas drainage pipe in the drainage hole, which prevents further advancement, and cannot reach the set sealing position, the designed sealing length, and the sealing time is also difficult. control, the effect of drilling and sealing is not ideal, and the success rate of sealing is low, which affects the effect of gas drainage

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