Study on the influence in drainage system of CBM wells brought by using ascending frequency technology

In view of the mechanical structure of CBM gas well sucker rod pump system, used the classical kinetic method to analyze the influences in drainage system of CBM wells bring by using `ascending frequency´ technology. The relationships between the imbalance degree of counterbalance and below influences are also analyzed. The results indicated that, `ascending frequency´ technology scheme could make the crank speed have great changes, but did not have obvious influence to the crank torque in cut direction, polished rod velocity and acceleration would be greatly increased by these influences, this could lead to the increase of polished rod load. The actual jig frequency is greater than the set jig frequency while using `ascending frequency´ technology. The relationship between the imbalance degree of counterbalance and influence is: the greater of the imbalance degree, the greater of the influence. So, a check combined with working parameters is necessary to determine whether polished rod load would exceed the stress limitation. Thus, we can get a reasonable work condition.