Beijing China Coal Sets a New Benchmark in Domestic Raise Drilling Technology 27 Dec 2020
Recently, the 1# diversion water inclined shaft pilot shaft project of Fujian Xiamen Pumped-storage Power Station has been successfully completed ,it is constructed by Beijing China Coal Mine Engineering Co., Ltd. (which is referred as' Beijing China Coal '). This pilot well has an inclination of 385m and an inclination angle of 55°. It is constructed by raise drilling. It is currently the largest 400m long inclined well project in China with a reaming diameter of 2.5m. (the previous maximum diameter was 2.0m). Technological development has set a new benchmark. The project uses the BMC-D90 directional drilling rig independently for pilot hole construction , and the BMC600 raise boring rig is uesed for reaming construction,which are developed by Beijing China Coal. The maximum reaming drilling speed is 18m/d, in order to shorten the key line construction period of the overall project.
The main engineering of the Xiamen pumped storage project is 4 long inclined wells of 400m level, which have the characteristics of high uniaxial compressive strength of the rock (up to 127MPa), complex geological structure, difficult to control well inclination and azimuth, high drilling deflection rate and high equipment requirements. The 2.5m reaming drill bit weighs 10 tons (the 2.0m reaming drill bit weighs 5 tons),the risk of the drill bit entering and exiting the hole is high, and the overall construction is very difficult. Beijing China Coal made full use of its overall advantages in raise well drilling equipment, technology, scientific research, construction experience, etc., and held several technical seminars to determine safe and reasonable construction plans. The project department meticulously organizes construction and manages in strict accordance with the company's safety standardization to ensure the safe and orderly construction of the project.