Analysis and study on liquid loading process of downhole throttle in Sulige Gas Field

The downhole throttle technique is wildly used in development of Sulige Gas Field. With gas field development, gradual decrease of gas well pressure and output, downhole throttle cannot drain the liquid, causing liquid loading of well bore and large bottom back pressure, thus affecting the production of gas well. To prolong the period before the gas well becomes low productivity and low efficiency, it is necessary to study the reasonable fishing time of throttle. For the liquid loading of well bore in downhole throttling condition and problem solution, the methods such as software simulation and analysis of production and testing data, are adopted. The flow pattern analysis of liquid loading of well bore under downhole throttling well, process study and analysis of main control mechanism under different liquid loading show that the starting point of rapid decrease of throttling gas well pressure and output is when the liquid loading of throttle starts and defines the reasonable fishing time of throttle of liquid loading well of Sulige Gas Field based on this to provide theories and practical experience for throttle fishing time on production site.