基于PD密封材料的瓦斯测压钻孔封孔新技术

摘要

为了解决大社矿瓦斯测压钻孔封孔质量低的问题,提出了基于PD密封材料的瓦斯测压钻孔封孔新技术,在传统“两堵一注”水泥砂浆封孔工艺中增加了PD密封材料,同时增加了一次带压注浆过程,阐述了新封孔技术的封孔原理和工艺流程,并在煤矿现场进行了2种测压钻孔封孔效果的对比试验.结果表明:与传统的“两堵一注”水泥砂浆封孔技术相比,在相同的地质单元施工参数相同的钻孔,新的封孔技术所测煤层瓦斯压力为1.38 MPa,大于传统封孔技术所测最大值0.90 MPa,说明基于PD密封材料的瓦斯测压钻孔封孔新技术密封效果更好,明显提高了钻孔的密封性,30 d后瓦斯压力没有出现回落,延长了封孔段工作时间,所测瓦斯压力提高了0.48 MPa,测压准确性更高.%In order to solve a poor borehole sealing quality of the gas pressure measuring borehole in Dashe Mine,the paper provided a new borehole sealing technology of the gas pressure measuring borehole based on PD sealing material.The PD sealing material was added to the conventional two sealing and one grouting cement grout borehole sealing technique.Meanwhile,a pressurized grouting process was added.The paper stated the borehole sealing principle and technique process of the new borehole sealing technology.A comparison experiment on the borehole sealing effect of the two type pressure measuring boreholes was conducted in the mine site.The results showed that in comparison with the conventional two sealing and one grouting cement grout sealing technology,in the same borehole with the same geological unit construction parameter,the seam gas pressure value measured with the new borehole sealing technology was 1.38 MPa and was bigger than measured max value 0.90 MPa with the conventional borehole sealing technology.Based on the PD sealing material,the sealing effect of the new borehole sealing technology for the gas pressure measuring borehole was better and could obviously improve the sealing of the borehole.After 30 days,there was no pressure drop occurred on the gas pressure,the working time at the borehole sealing section was expanded,the gas pressure value measured was improved by 0.48 MPa and the accuracy of the pressure measured was more higher.