1State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, P. R. China
2Downhole Services Company, BHDC, Renqiu 062550, China
3Marine Oil Production Plant, Shengli Oilfield Company, SINOPEC, Dongying City, Shandong Province 257237, China
4Engineering Technology Research Institute of PetroChina Southwest Oil & Gasfield Company, Chengdu 610017, Sichuan, China
5Down-hole Service Company of CNPC Chuanqing Drilling Engineering Company Limited, Chengdu 610051, Sichuan, China
6Shanxi Coalbed Methane Exploration and Development Branch Company, PetroChina Huabei Oilfield Company, Changzhi, Shanxi 046000, China