Novel cable measurement while drilling device used for directional drilling in coal mine

Abstract

In order to solve problems of short usage time, poor signal stability, high fault ratio and high maintenance cost of existing cable measurement while drilling device for coal mine drilling which was powered by battery in hole, a technology scheme was proposed which used explosion-proof computer to power supply measuring tube in hole. By researching design of constant voltage source and signal demodulation of explosion-proof computer, design of parameter measurement, secondary power supply and signal carrier transmission work of measuring tube and development of measurement software, a cable measurement while drilling device was developed which was powered by explosion-proof computer. Measurement accuracy test of the device is taken in a professional organizations as well as work stability test in Shizuishan No.2 Coal Mine and depth test in Sihe Coal Mine. The tests results show that the device is feasible with higher measuring accuracy than the design value, and has strong working stability with drilling transmission distance of 1 881 m. The device can meet need of directional drilling with different types in coal mine.

Keywords

• directional drilling in coal mine
• cable measurement while drilling device
• powered by explosion-proof computer
• measuring tube