Shandong University

Yixin Liu

Gang Wang

Weimin Cheng

Guanhua Ni

Qiming Huang

Zhen Liu

Lulu Sun

Yanbin Yu

Zhiyuan Liu

Jingna Xie

Kai Dong

Xiangjie Qin

Jiuyuan Fan

A deep low-permeability gassy seam drilling-slitting-sealing-fracturing drilling device includes a drilling control system, a high-pressure water power system, a water pressure grading control system and a fracturing and sealing control system. The drilling control system adjusts a drilling direction a water supply pressure of the drill rod, the high-pressure water power system supplies high-pressure water with different pressures to the device, and the water pressure grading control system ensures that a water pressure for flushing drill cuttings is less than 5 MPa, a water pressure for slitting in a direction perpendicular to a length of the drill rod is 25-35 MPa, a water pressure for sealing with a borehole sealing capsule is 35-40 MPa, and a water pressure for further pressure relief and permeability increasing of a coal seam is 40-50 MPa. The fracturing and sealing control system controls borehole sealing and hydrofracturing operations.

Drilling-slitting-sealing-fracturing device and method for a deep low-permeability gassy coal seam

A full-length screen pipe hole protection device and method with pressurized hole packing in a soft coal seam relates to the field of gas drainage technologies. The device includes a grouting system, a drainage system and a hole fixing system. The grouting system injects a pressurized sealing material into a borehole through a pressure pump to increase a sealing effect of the borehole. The drainage system drains gas in the middle of air holes on metal baffle plates and hole fixing screen pipes through a drainage pipe to increase flowability of gas. The hole fixing system is inside the borehole and fixed with the metal baffle plates, and the hole fixing screen pipes are fixedly connected with each other through fitting mouths and fitting buckles. The device is fixedly mounted in the gas drainage borehole. After hole packing, the drainage pipe is connected with a drainage pump to drain gas.

Full-length screen pipe hole protection device and method with pressurized hole packing in soft coal seam

Growing community of inventors

Qingdao, China

Yixin Liu