Abstract
This paper presents a study of Sucker Rod Pump (SRP) systems operating in Murphy Oil's Eagle Ford unconventional shale wells located in South Texas, USA. Lessons learned and recommended practices will be shared which were developed to improve SRP system performance and reduce system failure frequency. The company installed its first SRP during 2012. This system incorporated a variable speed drive (VSD), portable generator and electric prime mover. Murphy currently produces more than 550 wells using SRP systems across the Eagle Ford over a widely dispersed geographic region.
As the number of SRP installations grew, early life and repeat failures started to occur. The most frequent types of failure are discussed in this paper. Lessons learned and recommended practices are shared. A study of the entire SRP was conducted which included the surface and downhole equipment, variable speed drive (VSD) and operating strategy. A data base was created to document information on every installation and failure. Equipment sub-systems were created to help with analysis and included the tubing, sucker rods and bottomhole pump.
A new set of guidelines and strategies have been developed to enhance overall system reliability and operation. The failure data base has proven critical to identify performance gaps and specific opportunities to improve the SRP system. The data base revealed 52% of all failures are related to the pump system, 22% are tubing system and 26% are sucker rod system. The failure frequency is now visible for each Murphy operating area and sub-system which helps further identify opportunities for reliability improvement. These efforts have resulted in a failure frequency reduction of 50% from 2014 to 2016.
A number of challenges have been addressed to achieve successful SRP operation in Murphy's Eagle Ford shale wells. Following traditional best practices and "rules of thumb" have not always delivered expected performance and run life. This paper discusses key factors identified during the continuous improvement journey and provides operators a benchmark of SRP system in a similar application.
