Wireless Monitoring of Downhole Pressure Based on Tubing Transmission

Downhole pressure is an important parameter for evaluating the production status of wells. A wireless monitoring system was designed downhole which consists two parts, i.e., tool and wellhead tool. The tubing used as information transmission medium between parts. includes four sensors, measured results will be applied to in form alternating voltage with a frequency 2.5 Hz. amplitude output by related magnitude pressure. measures decodes signal uploaded through tubing, decoded result transmitted host computer ground cable. model well equivalent resistance network. Simulation analysis indicates that received negatively correlated depth positively formation resistivity. tested gas-producing wells southwestern China. test verified stability reliability monitoring. It also confirmed strength at first time not affected structure wellbore. scheme introduced this paper can extended other parameters such temperature.