Device for testing stability of drilled hole for coal bed gas extraction

• Main Authors: SONG DAZHAO, WANG ENYUAN, QIE LIMIN, MENG XIANYI, DAI LINJU
• Format: Patent
• Language: Chinese; English
• Published: 07.05.2014
• Subjects: EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, ORDRAINING IN OR OF MINES OR TUNNELS

The utility model discloses a device for testing stability of a drilled hole for coal bed gas extraction, and belongs to devices for testing stability of drilled holes for coal bed gas extraction. The device for testing stability of the drilled hole for coal bed gas extraction comprises a pressure sensor, a guide rod, a pressure data acquisition instrument and a pressure pump, wherein the pressure sensor is composed of a pressure sensing capsule and a liquid inlet, and the guide rod is composed of a PVC pipe, a clamping groove and a quick coupling. Pressurization is carried out on the pressure sensing capsule by using the pressure pump, so that the pressure sensing capsule expands, but pressure sensing capsule does not make contact with the hole wall of the drilled hole for gas extraction, the drilled hole contracts and deforms under the action of external force, changes of the pressure nearby are sensed through coupling contact between the pressure sensing capsule and the hole wall of the deformed drilled ho