NOV develops top-drive upgrade for cost-effective performance upgrades in the Permian
HOUSTON -- Demand in the Permian basin for cost-effective ways of improving performance continues to increase. While a simple solution might involve purchasing entirely new equipment, in many cases this isn’t feasible due to both current constraints on capital expenditures and unacceptable downtime caused by long lead times for newbuilds. To address this issue, National Oilwell Varco (NOV) developed an upgrade package—the TDS-11SAE—for its top drives to elevate their performance beyond standard levels.
The package builds upon the wide field implementation of the original TDS-11SA top drive, which currently has more than 2,000 units in use. NOV recognized that an upgrade package would be of benefit to drilling contractors needing to differentiate their fleet, particularly with competition as intense as it is in the current cost environment. Furthermore, the widespread use of the original top drive, particularly in active plays such as the Permian, meant that service delivery and execution could be expedited without sacrificing quality.
The new top drive package represents an enhancement to the original model that meets the needs of the land drilling market for higher torque and higher speeds, achieving 32,120 ft-lb at 180 RPM at the drill stem, while also addressing current market demand for an upgrade that extends top-drive life and reduces overall cost. The upgrade consists of two new 600-hp induction motors and gearbox internals that are retrofitted to a customer-owned TDS-11SA top drive.
After collaborating with major engineering partners to conduct a comprehensive analysis of the top drive's gearbox, NOV determined that hot stress and fatigue would be affected by the increase in horsepower. The improvements to the gearbox enable the top drive upgrade by ensuring that expected service life and design safety factors are maintained, even in challenging environments like the Permian. The dramatic increase in horsepower yields significantly more torque and enables drilling of wells beyond the technical limits of standard top drives while maintaining a similar rig footprint, only adding 6 in. to the original configuration. Additionally, 500-ton main thrust bearing ensures the hoisting capacity to handle heavy pipe.
There are distinct benefits that differentiate the new top drive upgrade package versus using third parties to install new motors with higher horsepower. The upgrade is less expensive than installing new motors, provides significant improvements to performance, and ensures customers are receiving the quality and experience of the OEM when upgrading this critical piece of drilling equipment. The upgrade can be performed at an NOV repair shop during standard CAT-IV or five-year overhaul services with minimum downtime.
