加临时浮力塞双塞自平衡下管法参数计算方法及工程应用

Calculation method and engineering application of parameters for sinking casing pipe by double plug self balancing method with temporary buoyancy plug

在煤矿瓦斯抽排井钻孔施工过程中需要下入超重特大套管,而套管总质量一般远超施工钻机提拉最大量程,研发合适的下管工艺对确保套管成功下放至关重要。为此,基于浮力定律推导了加临时浮力塞双塞自平衡下管法下管过程中各参数的理论计算公式,介绍了采用该方法下放超重特大套管的流程,并在顾北煤矿瓦斯抽采系统改扩建钻孔施工中进行工程示范,按照理论计算公式获得的下管过程中的各项设计参数进行施工,实现了超重特大套管的安全下放,研究结果可为超重特大套管浮力法下管的参数设计提供一定参考。

In the process of drilling construction of gas pumping-exhaust well in coal mine,it is necessary to put in super heavy and extra large casing pipe,and the total quality of casing pipe is generally far more than the maximum range of construction drilling rig lifting.It is very necessary to develop appropriate casing technology to ensure the successful sinking of casing pipe.Therefore,based on the buoyancy law,theoretical calculation formulas for various parameters in the process of sinking casing pipe by double plug self balancing method with temporary buoyancy plug were derived.It introduces the process of using this method to sink super heavy and extra large casing pipe,and demonstrates the engineering demonstration in the drilling construction of the gas extraction system renovation and expansion in Gubei Coal Mine.According to the design parameters obtained by the theoretical calculation method,the construction was carried out,and the safe sinking of super heavy and extra large casing pipe was realized.The research results can provide certain references for the parameters design of sinking super heavy and extra large casing pipe by buoyancy method.