Case Histories of Running Progressing Cavity Pumps with Submersible Permanent Magnet Motors

Abstract

Abstract Although conventional rod driven Progressing Cavity Pumps (PCPs) have been in use since the early 1980‘s, the industry has continued to seek alternative methods of powering the system. Initial attempts were made using conventional electric submersible induction motors however their high synchronous speeds proved to be problematic. These inherent high speeds resulted in developing motors with more poles (hence a slower synchronous speed) as well as down-hole gear boxes. All of this was in an attempt to get the motor speeds down to an acceptable range whereby the progressing cavity pump would work successfully. Using Submersible Permanent Magnet Motors (PMM) rather than conventional Induction Motors (IM) to drive the PCP is an effective and efficient method directly powering the PCP as well as eliminating the need for a downhole gear. In addition, the PMM motor’s power density is much higher, thus the motor length is significantly shorter which enhances deployment of the system in deviated wells. Over 1000 PCP-PMMs have been successfully installed in several Russian fields in differing applications with more than 250 still in operation. Their average run life exceeds 200 days and is typically in the range of 360-600 days with a maximum run time of 1091 days. This paper will share numerous case histories on PCP-PMM installations by providing a general review of the application, a summary of the PMM-PCP components installed and the overall design approach that led to the long term success.