Coal Mining & Designing Department, Tiandi Science & Technology Co., Ltd. Yankuang Group Co., Ltd. Shaanxi
Future Energy and Chemical Co., Ltd.

For the problems of surrounding rock control for 8 m large mining height, stability and reliability of hydraulic support and large coal quantity adaptive con tinuous operation, relevant research was carried out. First coupling mechanical model of hydraulic support and surrounding rock was established, the reasonable workin g resistance of ultra large height hydraulic support was determined by two-factor control method and three-level coactions face guard mechanism and the double-telesc opic prop was designed which could control rib spalling and roof pressure efficiently; improving the relability of the 8. 2 m mining height hydraulic support by using high -tensile structural steel and new process of intelligent welding; based on the non-pole soft start, supersize chain and transmission system and the continuous crushing device of electric direct drive tooth roller, the paper developed ultra large coal quantity self-adaptive scraper conveyor; Finally, by comprehensive using the multiple stu dy, such as coal mining machine walk transmission technology, folding belt conveyor.advanced hydraulic support and so on, the first set of 8 m mining height complete sets of equipment was developed and the industrial test was carried out in No.108 working face in Jinjitan Coal Mine of Yankuang Group. The tests indicated that the co mplete set of equipment could control roof and coal wall effectively, which had good stability and reliability; the coal flow was smooth and no big lumps of coal were bloc ked. During the test, the working face was up to 57 000 tons, and the monthly output reached 1. 5 million tons.

国家重点基础研究发展计划(973计划)资助项目(2014CB046302)；国家自然科学基金重点资助项目(U1610251)；