The Development of a New Sensor for Tool Face Angle Based on Electrical Resistance

Abstract

Trenchless technology is a type of construction that requires pipelines to be laid in a subsurface horizontal hole drilled by a trenchless drilling rig. To prevent drilling accidents during construction, the drilling trajectory needs to be controlled in real time according to the value of the tool face angle. However, existing tool face angle sensors cannot precisely control a trenchless drilling course due to a number of limitations such as low resolution, large temperature drift, and high requirements for accurate installation. In this regard, this paper presented a new tool face angle sensor based on the change in electrical resistance value. The tests mainly include four aspects, namely, accuracy, repeatability, resolution, and temperature drift. Numbers of tests showed that the measurement error was ±6 degrees, the repeatability was 2.54%, the minimum resolution was 6 degrees, and the temperature drift had no effect during the temperature changes from 0 to 80 degrees, which proved that the sensor is applicable for practical trenchless working conditions.