Abstract: The Sanjiang-Mulenghe area is rich in coalbed methane, which is mainly distributed in Jixi, Boli, Shuangyashan and Hegang basins. Drilling for coal core is an important part of coalbed methane development evaluation. Recovery rate of coal core directly affects the determination of the coal seam structure and gas content, and further affects drilling quality, coal resources and evaluation of coalbed methane development. There are many factors affecting the coal core recovery rate. Coring tools, coring procedures, core drilling methods, core handling techniques, and geological characteristics of the coal seam itself will affect the coal core recovery rate. In this paper the drilling data of coal seams in Hegang and Jixi areas of Heilongjiang Province is mainly investigated. The research is carried out by optimizing and improving the structure of coring drills, appropriately adjusting drilling parameters and scientific organization and management. Then, the recovery rate of coal core were found improved remarkably after the application in several wells in the field. The coal core recovery rate of block coal seam is over 92% and that of powdery coal seam is increased to more than 83% . It is of great significance to the development of coal seam wells.

摘要： 三江 －穆棱河地区煤层气资源丰富，主要分布在鸡西、勃利、双鸭山、鹤岗等盆地，取心是煤层气开发评价不可缺少的一项重要工程环节。煤心收获率的高低直接影响煤层结构、煤层含气量数据的确定，影响钻井质量和煤炭资源、煤层气开发的评价。取心工具、取心规程、取心钻进方法、取心操作技巧以及煤层本身的地质特性等诸多因素都将影响着煤心收获率的高低。在对黑龙江鹤岗和鸡西地区的煤层取心钻探资料调研基础上，通过优化改进取心钻具结构，合理调控钻进参数，科学组织管理等措施，经现场多口井的应用，块煤煤心收获率提高到９２％以上，粉煤煤心收获率提高到 ８３％以上，成效显著，对煤层气开发评价具有重要意义。

关键词: 煤心收获率, 钻具结构, 钻进参数, 组织管理