针对松软煤层钻孔坍塌、瓦斯抽放效率低的问题,开发了一种新型筛管护壁工艺。该工艺旨在退钻之前利用钻杆内径将筛管下入孔底,确保瓦斯抽放通道的畅通,提高瓦斯抽放效率。为了满足该工艺的要求,研制开发了大通孔开闭式钻头、通径钻杆和筛管固定装置。通过在新集一矿的试验,该工艺的筛管下放率达到了99%以上,真正实现了“钻到位,管到底”的目标,瓦斯抽采浓度得到了有效提高。 Aimed at the problem of loose borehole collapse and low gas drainage efficiency, a new type of screen pipe wall protection technology has been developed. The purpose of the process is to drill down the inner diameter of the drill pipe before drilling into the bottom of the hole to ensure the smooth flow of gas drainage and improve gas drainage efficiency. In order to meet the requirements of the process, developed a large-hole open-close drill, drill pipe diameter and screen fixing device. Through the test at Xinji No. 1 Mine, the dewatering rate of the screen reached over 99%, which truly achieved the goal of “drilling in place and tube running to the end”, and the concentration of gas drainage was effectively increased.