No abstract

Progressing cavity pumps (PCPs) have proven to be a successful and reliable artificial lift system for production of heavy oil reservoirs over the past few decades. The application of PCP technology for production of oil wells in general continues to expand rapidly due to ongoing advances in versatility, production rate and lift capacity, durability, and economy. As a result, the application envelope for PCP systems has grown substantially to the point where these systems now successfully compete in many areas that were traditionally reserved to Rod Pump and ESP technologies. The development and implementation of a new type of PCP, namely the "all metal" (non-elastomeric) progressing cavity pump has been driven by the need to achieve significant improvements in the performance and run life of PCPs in high temperature/thermal well applications, and wells producing fluids which cause rapid chemical and/or mechanical degradation of elastomeric PCPs. This paper describes the successful implementation and use of Metal PCP systems in a diverse range of extra heavy oil wells located along the northern coast of Cuba beginning in July 2005. This is believed to be the first major use of this technology in such a field application. The paper also compares the performance and run lives achieved with the Metal PCPs to that of elastomeric PCPs in the same application. In general, the field trial results have demonstrated that the strong resistance of Metal PCPs to chemical and mechanical degradation makes them a good alternative for the cold production of heavy and extra heavy oil with relatively high bottomhole temperatures and high aromatic, CO2 or H2S concentrations. Introduction Progressing cavity pumps (PCPs), first developed and patented by Rene Moineau (Moineau, 1931), have found numerous applications in many industries as a means to efficiently transfer, transport and/or lift fluids of a diverse nature. The use of PCPs as an artificial lift method for oil wells has gained increasing acceptance since their first commercial use in heavy oil applications in the 1980's, and they have now become the lift method of choice in numerous oil field developments worldwide (Doval et al, 2007). This paper describes the use of PCP systems to produce extra heavy oil from a number of extended reach horizontal wells located along the northern coast of Cuba. The field experience includes numerous conventional (elastomeric) PCP installations over the past 8 years, as well as the deployment of several recently developed "all metal" PCPs beginning in July 2005 - this is believed to be the first major use of this new technology in such a primary production application. Relevant field data has been collected and analyzed to assess and compare the performance and service life of the various conventional and all metal PCPs.