.pdf asset-performance field_planning_color fit_for_purpose_color production_optimization_recovery_color kpi-box kpi-money kpi-time ::before

An operator with a deepwater well in the Gulf of Mexico needed to perform a casing exit with a window depth of 25,803 ft (7,864.8 m) in 95 /8-in. casing. Before beginning the job, Baker Hughes, a GE company (BHGE), recommended a designated wellbore cleanup run to remove any debris that could interfere with the operation. The customer declined.

At the customer’s direction, we ran our WindowMaster™ G2 whipstock system and PathMAKER™ polycrystalline diamond cutter (PDC) window mill assembly in hole, but the system began taking weight at approximately 1,300 ft (396.2 m) above the target depth. Several attempts resulted in the bottomhole assembly (BHA) reaching a final depth of only 24,661 ft (7,516.7 m), which was 1,142 ft (348.1 m) short of the target depth. The BHA was pulled out of hole when it was clear that no further progress could be made. On inspection, it was discovered that the whipstock, bottom-trip anchor, and whipstock extension had been left in the hole. The BHGE team reacted quickly and deployed a fixed-lug retrieval tool to fish the whipstock, a downhole sensor to collect BHA data, and X-Treme Clean™ extreme performance (XP) magnets to collect debris during the retrieval. To accelerate the fishing operation, the operator agreed to add xSight™ smart intervention services, which collect real-time data to help optimize operations and reduce NPT.

The fixed-lug retrieval tool fits into a dovetail slot on the whipstock, which is 2½ in. (6.35 cm) wide and has approximately 1 /16-in. (.159-cm) clearance. This would normally make the fishing operation extremely challenging and time consuming, but using xSight services helped accurately measure downhole weight-on-bit, torque, and orientation from the surface. This type of real-time data provides a tremendous advantage in deep fishing operations.

Challenges & Results


  • Perform a casing exit in 95 /8-in. casing with window depth at 25,803 ft
  • Fish whipstock, anchor, and extension out of the hole before beginning
  • Connect to a 2½-in. dovetail slot with a 1 /16-in. clearance on the whipstock at 24,661 ft
  • Reduce NPT and speed up the operation as much as possible through the use of real-time downhole data and feedback


  • Reduced NPT
  • Saved several days of rig time
  • Increased overall efficiency through comprehensive casing-exit solution
  • Milled the window in 5 hr and 39 min and drilled 40 ft of rathole
  • Collected a total of 416.5 lb of debris using XP magnets