Technical analysis on coalbed methane continued drainage system with rod pump and speed tube

In order to solve the mismatching problems of the production equipment with the water production and gas production due to the production condition se riously changed when the gas drainage of the coalbed methane wells were transited from the early period to the late period, based on the analysis on the drainage feat ures of the rod pump and speed tube, a continued well switching gas drainage technical method was provided with the rod pump-speed tube drainage, a feasibility anal ysis of the technique was completed and the design on the technical process of the overall switching operation was completed. The study showed that the application of the technology could avoid the repair operation of the well. Under the condition of non stop operation, the rod drainage technology could rapidly replace the process of t he speed tube drainage technology. Thus, the damage to the reservoir of the coalbed methane well could be reduced, the continued drainage operation of the coalbed methane well could be ensured and the stable production time and trouble-free drainage time of the coalbed methane well could be prolonged.