Efficiently drill curve and long lateral sections in shale plays with application-specific PDC bits.
已发表: 08/05/2014
已发表: 08/05/2014
Shell was drilling four directional shale wells in Neuquén, Argentina that were characterized by low compressive strengths. Each one had a curve in the Quintuco formation with a lateral in the Vaca Muerta formation.
The two wells in the Sierras Blanca block were drilled using first-generation Spear shale-optimized steel-body PDC drill bits on a conventional downhole motor with the curve and lateral drilled separately.
The first well was drilled using an SDi513 Spear bit on a PowerDrive Archer high build rate RSS assembly with both sections completed by the same bit in one run. In the second well, the operator wanted to drill an 8.5-in interval from surface casing at 2,668 m to a TD of 4,078 m in one run. To achieve that goal, the operator had to improve ROP in the lateral and maintain bit steerability in the curve.
To maximize bit performance, Schlumberger recommended the next-generation Spear SDi516 bit with five blades and 16-mm cutters. The larger and more aggressive cutters allowed for takeoff in the lateral and a smooth toolface control for the curve. In addition, the bit was designed using a cutter and gauge configuration optimized for the PowerDrive Archer RSS. The customized design ensured smooth sliding and improved rotating capabilities while building the curve and maximizing ROP in the lateral.
Furthermore, the SDi516 differentiates itself from its predecessor with two enhanced hydraulic features: shale evacuation channels and a super bullet body design. These features significantly reduce drill time by combating factors that slow down operations such as long lateral sections and low hydraulic horsepower caused by poor pumping capabilities.
The five-bladed SDi516 Spear PDC bit with 16-mm cutters run on a PowerDrive Archer RSS drilled 1,410 m in 89.8 h at a ROP of 15.7 m/h. Compared with the first well that was drilled to 1,213 m in 105.7 h at an ROP of 11.5 m/h, the second well increased ROP by 8.5%, saving the operator 15.9 h.
Challenge: Increase ROP in the lateral while maintaining steerability in the curve section of the second well, which is composed of unconventional shale.
Solution: Run next generation Spear shale-optimized steel-body PDC drill bit on PowerDrive Archer high build rate rotary steerable system (RSS) for improved smooth sliding, rotating capabilities, and hydraulic features.
Results: