A Pumping Well Wireless Communication Technology Based on Load Pulse of Sucker Rod

Abstract

Abstract Pumping wells are characterized by fluid discontinuity, complex media, and periodic pump inspection. The data transmission technology, such as preset cable and pressure wave, which are widely used in injection wells, suffers from many problems when applied in pumping wells, such as high cost, complicated technique, and not suitable for pump inspection operation. As a result, there is an urgent need to develop low-cost wireless transmission technologies suitable for pumping well. This paper proposes an innovative wireless communication technology for pumping well based on the load pulse of sucker rod. Its main components include a downhole load pulse generator (DLPG) and a ground communication controller (GCC). The DLPG is installed between the tubing pump barrel and the stationary valve and is equipped with an 8.5 mm diameter stepless adjusting valve that provides access between the pump chamber and annulus. During the operation of the pumping unit, adjusting the opening or closing state of the adjusting valve can change the working state of the tubing pump and thus change the normal lifting load of the pumping unit. Therefore, wireless uploading of downhole data can be realized by modulating downhole data into lifting load pulse and demodulating of load pulse by the GCC. The principle and transmission characteristics of the technology have been tested in Jilin Oilfield. The results show that the opening or closing of the adjusting valve of the DLPG generate controllable and identifiable lifting load pulses at the wellhead. Moreover, with the increasing opening of the adjusting valve, the lifting load increases significantly. The average load when the adjusting valve is fully opened is 33.65kN, an increase of 64.7% compared with the normal lifting load. When the adjusting valve is completely closed, the lifting load quickly drops to normal. In addition, at 980 m pump setting depth, the response delay of lifting load dynamic change is very small. The pressure sensor of the DLPG can recognize the pressure changes of the pump chamber and accurately judge the up and down stroke. Using stroke recognition and load pulse automatic control, the downhole data uploading is successfully realized, and the technical principle and feasibility are verified. This technology realizes wireless uploading of downhole data without changing the structure and working mode of the existing pumping well. It has the advantages of simple structure, easy installation, low cost, and no influence of pump inspection operation. It can be adapted to the current situation of the large number and wide distribution of pumping wells in China, and is expected to provide a new means of communication for improving the downhole understanding of pumping wells.