Unlocking New Solution in Brown Field Production: Innovative & Advanced THM (Tubing Heavy Wall Mechanical) Pump Improvement Method with Cost-Effective Approach

Abstract

Mature oil fields have various obstacles in producing oil efficiently. In Rantau Field, the reservoir pressure has already been depleted and nowadays the development using waterflood technology initiated to deploy for Zone Z-AAA. Evaluation of various strategies conducted to maximize production in waterflood Zone development (Z-AAA), minimizing cost and extending the field's economic life. Sucker rod pump (SRP) is the most artificial lift used in Rantau Field because SRP is one of the low -cost artificial lift, about 68.61% in total. The cost-efficient solution is done by repairing the downhole pump for SRP (tubing pump / THM Pump) after well service and re - installed it. The challenge from using repaired tubing pump is the leakage of the pump. The authors conducted FMEA analysis to solve that p roblem. The tubing pump has a hold-down mechanism on its standing valve assembly and does not have backup seal when the hold-down ring is damaged, and yield strength of the hold-down ring is less than the seating nipple. A finite element simulation with mess skewness 0.2 was carried out to support the analysis to determine the improved design of standing valve assembly. From the simulation, the hold-down ring with fit interference could not hold the force from the operational load, especially for bump- down jobs when the pump gets stuck. The stress that impacts the hold-down ring could reach 392 MPa (156% of its yield strength). The author modified the hold-down ring design into a threaded design complete with O-ring sealing, then called TSV. The stress impacted to TSV could reach 144 MPa (57% of its yield strength) in the simulation. To validate the finite element result, the author conducted a pressure test with a vacuum tester. The pressure test was applied at 500 Psi and could be held for 5 minutes. The next step i s the installation of TSV in three wells. As the result of improving the design of standing valve assembly, the repaired tubing pump could be reinstalled in another we ll without changing the standing valve components and it has decreased the pump failure during the operation of the pump. Since the repaired tubing pump could be used repeatedly, new purchases of tubing pumps could be minimized, and it can suppress the production cost of mature oil fields in general.