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  • VFD top drive, power spider and stabbing system

    Tesco Corp. added a 750-ton AC top drive to its lineup, enhancing its range of top drives to cover 95% of the industry’s onshore and offshore needs. The latest unit, the 750ECIX1350/1500, features Permanent Magnet (PM) motors, a new Variable Frequency Drive (VFD) system, and provides up to 1,500 hp, Fig. 1. The new VFD system is based on commercial drive technology and uses the new eDrive interface between the VFD and the DRS Power Technologies’ PA44 PM motors. The control interface and motor characteristics are configured specifically for the control requirements specified by DRS and Tesco. The drive logic is programmed to allow the ECI and ECIX top drive systems to operate at constant speed for drilling ahead or with constant torque, as when making or breaking drillstring members. Further, the drive logic permits speed and torque limits to be set.

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2013 Fracturing Technology

2013 Fracturing Technology