Multipurpose active/passive motion compensation system
A microprocessor-controlled active/passive motion compensation system has been developed for deploying a variety of geotechnical in-situ testing devices with mobile drilling rigs from low-cost service vessels. The light-weight rotary heave compensator incorporates a hydraulic motor as the compensator actuator and a servo-controlled closed loop pump to reduce the air storage and power requirements. Unique features of the system are the use of inertial sensors to measure three components of boat motion, the ability to run the system in active/passive or passive modes, and the ability to automatically lower the drillstring at a constant velocity while maintaining motion compensation. Quantitative measurements made during sea trials offshore California yielded motion compensation accuracy approaching 98 percent which is much better than the compensation achieved with passive systems. Results are presented from offshore in-situ testing with a cone penetrometer, a vane shear device, and a suspension PS logger. The system can also be used for other offshore applications.
- Research Organization:
- Woodward-Clyde Oceaneering
- OSTI ID:
- 6418162
- Report Number(s):
- CONF-8405208-
- Journal Information:
- Proc., Annu. Offshore Technol. Conf.; (United States), Vol. 2; Conference: 16. annual offshore technology conference, Houston, TX, USA, 7 May 1984
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
42 ENGINEERING
DRILLING RIGS
WELL LOGGING EQUIPMENT
OFFSHORE DRILLING
COMPUTERIZED CONTROL SYSTEMS
ACCURACY
COST
DRILL BITS
DRILL PIPES
HOISTING
HYDRAULIC EQUIPMENT
MEASURING INSTRUMENTS
MICROPROCESSORS
MOTORS
PENETROMETERS
PUMPS
SEISMIC WAVES
SERVOMECHANISMS
SONIC LOGGING
TESTING
VELOCITY
COMPUTERS
CONTROL EQUIPMENT
CONTROL SYSTEMS
DRILLING
DRILLING EQUIPMENT
ELECTRONIC CIRCUITS
EQUIPMENT
MATERIALS HANDLING
MICROELECTRONIC CIRCUITS
PIPES
WELL LOGGING
020300* - Petroleum- Drilling & Production
423000 - Engineering- Marine Engineering- (1980-)