Data processing, Diagnosis and Optimum Design of Rod String for Numerically Controlled Pumping Wells

Abstract

Li Yugeng, China National Petroleum Corporation, SPE Member, Yu Xiaoqing, Xi'an Petroleum Institute, Wan Wanggeng, Xi'an Jiaotong University, Xu Yuangang, Xi'an Petroleum Institute, Yu Guoan, Xi'an petroleum Institute, SPE Member Abstract The structure, characteristic and primary parameters determination are briefly introduced for Numerically Controlled Pumping Unit is this paper. After data processing of diagnostic results for Numerically Controlled Pumping Unit, a diagnosis software and a software for designing the tapered rod string are developed. It is proved that these two softwares are reliable and have enough precision. Introduction Numerically Controlled Pumping Unit is completely numerically controlled and an embodiment of combining machinery with electricity, it was developed in 1992 by China National Petroleum Corporation, Baoji Oil Machinery Factory and China Northern Power Group. It has filled in the gap in oil machinery installment of China. It has the following advantages: it consumes less steel material and energy, its movement law is rational, the pumping efficiency can be raised and the pump inspection period will be lengthened. It is easy to adjust and convenient to operate. It has been tested in the oil fields of Dagang, Huabei and Daqing and has a good result. The test results from a well in Dagang Oil Field shows that the motor power factor is as high as 0.97, the motor efficiency is about 90%. power saving is 53.8%. The test results from two wells in Daqing Oil Field show that the pumping efficiency can be raised by 40%. In this paper, structure and primary parameters determination for Numerically Controlled Pumping Unit are presented. Analysis of movement law and data processing of diagnosis are presented. Fault diagnosis for Numerically Controlled Pumping wells and design of its rod string are finally presented. The structure of Numerically Controlled Pumping Unit is not very satisfactory and needs further improvement. It is necessary to develop a closed-loop control system for the Numerically Controlled Pumping Unit in case empty pumping, rod pans and motor's lacking phases take place. STRUCTURE OF NUMERICALLY CONTROLLED PUMPING UNIT AND DETERMINATION OF PRIMARY PARAMETERS Numerically Controlled Pumping Unit is drived from its top. It has two parts; one is machinery part and another is numerically controlled part. P. 197