摘要 |
The active deployment system (10, 10') comprises a passive cylinder system (410) coupled with an active cylinder system (400). The passive cylinder system (410) including a pre-charged accumulator (440), provides load balance for the equipment or other mass/load being deployed. Pressure provided to the blind end of the passive cylinder supports the load (60), such that the passive cylinder is balanced mid-stroke with the load hanging from a cable (30). A sheave arrangement (120, 130), placed at opposite ends of the passive cylinder-active cylinder combination, is used to introduce a line travel multiplier for cylinder displacement. The active cylinder is controlled hydraulically to add or remove load to/from the passive cylinder system in order to provide a compensating balance. The method comprises the steps of measuring a heave movement (velocity and direction), and adjusting the tension force applied to the cable (30) upon determining that the heave velocity exceeds a pre-selected critical velocity.
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