一种煤气井产出剖面热式气体流量计的设计

Design of Thermal Gas Flowmeter in Layered Gas Prodctivity Tests for CBM Wells

为解决低产煤气井分层产气量测试难题,设计并实现了一种井下恒流式热式气体流量计。阐述了热式气体质量流量计的测量原理,进行了热式气体流量计的总体设计,研制了现场试验样机,通过开展模拟井试验表明了恒流式热式气体质量流量计用于井下气体流量测量的可行性,测量小流量下限可达50 m^3/d,测试精度高,可达到煤层气井测试需求。

In order to solve the problem of layered gas productivity tests in the low yielding CBM wells, a constant current thermal mass flowmeter is designed. The measurement principle of the flowmeter is described. The overall design of the flowmeter is carried out, and the prototype is developed. By carrying out a large number of indoor dynamic experiments, the measurement feasibility of thermal gas flowmeter for downhole gas flow is proved well. The lower limit of measurement of the flowmeter is 50 m3/d, so its higher test precision can reach the CBM well test requirements.