SPT’s Submersible direct-driven screw pump technology has been applied in stable production of two horizontal wells in H218 block of Xinjiang Santanghu Oilfield for over 100 days, marking the success of this technology in horizontal well test in China’s oilfield for the first time!
The principle of the technology: a submersible motor directly drives the screw pump to rotate downhole and thus downhole liquid is lifted to surface; there is no need for sucker rod and mechanical reduction gear, thereby improving system efficiency, reducing energy consumption, greatly extending the production period of oil wells, and saving production cost. In comparison with the traditional screw pump production system, the technology has solved three difficult problems below: (1) a permanent magnet synchronous servo motor is used and there is no need for reducer, thus solving the technical design problem on a low-speed large torque motor in limited downhole space; (2) the motor is set downhole and the sucker rod is cancelled, thus thoroughly solving rod and pipe eccentric wear problem; (3) the matching system design is optimized and the screw pump is re-designed, thereby solving the motor burning problem at low liquid quantity. At present, only SPT has successfully developed this technology at first in domestic and foreign oil production technology industries and has popularized and applied it in the field.
Santanghu 218# block belongs to low porosity and ultra-low permeability reservoir, where oil is thick, the horizontal section of production wells is long, conventional lift is difficult, and it is difficult to solve the sucker rod and tubing friction problem. The submersible direct-driven pump was run in 2 test wells and the operations were favorably completed on May 23, with the pump setting depth being 1454.49m and 1409.34m respectively and the inclination at the pump setting depth being over 55°. At present, the daily power consumption of the screw pump is 80kWh and 68kWh respectively, the daily liquid production 7.27m3 and 8.3m3 respectively, and the water cut 40% and 50% respectively.
The application of the submersible direct-driven screw pump oil production technology in the two horizontal wells has reduced the power consumption of the mechanical production lift system with the conventional oil production technology, increased production time efficiency, solved the heavy oil lift problem, opened up a new approach for reducing manual labor intensity and development cost, made a key step for popularization and application of the submersible direct-driven screw pump oil production technology in heavy oil production of high-inclination wells and horizontal wells, and added a new powerful tool for our oil production technology services.