一、前言1965年，我队在煤系地层中钻进均是采用单管见煤，煤层顶板拿不好，许多煤层被打丢打薄，造成钻孔质量低劣。队党委对这一问题引起了重视，及时组织大家学习，提高思想认识。并提出了保证质量的两个百分之百的号召。即钻孔合格率达到100％，可 I. INTRODUCTION In 1965, our team drilled in coal strata using single pipe to see the coal. The roof of the coal seam was not good enough. Many coal beds were beaten and thinned, resulting in poor quality of drilling. The party committee of the party team has drawn great attention to this issue and organized all students to learn in a timely manner so as to raise their awareness of ideology. And put forward two hundred percent calls for guaranteeing quality. The drilling pass rate of 100% can be