In directional drilling, wellbores come in many shapes and forms. ESP equipment is often best suited for straight sections, however, in some instances, subsurface geology requires drillers to create more complex profiles with deviations or changes in direction known as doglegs. While subtle doglegs (<5 degrees / 100 ft) are sometimes drilled intentionally, severe doglegs can cause many problems, including key seating, increased torque and drag, and damage to the drillstring.
This year, an independent oil and gas E&P company was experiencing this very problem. The company was operating in a challenging asset with severe doglegs of 12-18 degrees/100 ft, and gas slugs exceeding 3100 GOR. To optimize production, they turned to Summit ESP.
Summit ESP developed a customized drill string solution with a deviator coupling, which enabled the ESP string to be run through the severe doglegs to the desired landing depth. Tandem QMAX XT gas separators were selected to separate gas from fluid before entering the pumps during normal operation and slugging events. Tubing and casing pressure transducers were installed for online monitoring (24/7/365) of these key parameters in real-time.
Seven days after start-up, Summit-Halliburton detected excessive casing head pressures, with spikes exceeding 365 psi. This resulted in unstable operation and limited production. To address the problem, Summit ESP’s Applications Engineering team recommended a casing head compressor, which would lower pressure and optimize performance. The company installed the compressor per this recommendation. The variable speed drive was then fine-tuned remotely through proprietary software for optimized system stability, achieving record draw down and production.
INITIAL PRODUCTION: 105 oil / 625 water / 200 gas
CURRENT PRODUCTION (with casing head compressor): 270 oil / 1200 water / 370 gas
Increased Annual Revenue: $2,970,000 *
*Assumes $50.00 per barrel oil price
Additional results can be seen in Figure 1 below.