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  • Rig Floor Equipment: Top drive's ac motor eliminates gearbox problems

    Looking to move top drive technology past the problems encountered with conventional gearbox-driven top drives, LeTourneau Technologie (LTI) Drilling Systems (formerly LEWCO) designed the DirectDrive line, its new top drive system requiring no gearbox. The core difference between the company’s new line of top drives and conventional systems is its elimination of problematic gearboxes. To replace the function of the gearbox, the company uses a patented AC motor which provides both power and control. Many of the problems encountered with top drive gearboxes result from their basic design, which must include large numbers of moving parts, along with bearings, seals, and associated lubrication systems. The basic design of the DirectDrive system eliminates all of these potential problems. The top drive is a fully integrated system, available in 250, 350, 500, and 1000 models. This system is designed around its patented Power Systems through-shaft design AC drilling motor.

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2013 Fracturing Technology

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