In the 30 years of operations on Suriname’s Tambaredjo field, the prime mechanism for lifting the 15.6 °API crude to surface has been that of progressing cavity pumps (PCPs). In the period from 2008 to 2012, an annual average of 580 downhole failures occurred, 54% of which were caused by tubing leaks. In an effort to reduce these tubing failures, a pilot program was commenced to install rod guides in wells with the highest failure rate and to install a 25-ft sucker rod directly above the pump.
Introduction
Currently, Staatsolie Maatschappij Suriname produces from the Tambaredjo, Calcutta, and Tambaredjo Northwest fields, as illustrated in Fig. 1 above. These oil fields are located in a marshy area on the coastal plain of Suriname approximately 55 km west of Paramaribo.
The crude oil contains low sulfur content (0.65 wt%) and 1 wt% asphaltene and has an average viscosity of 500 cp at reservoir conditions.