MacRack - the all-electric operating system for side-rolling hatch covers 

MacRack employs a combined rack-and-pinion drive and lifter system that makes separate hatch cover lifters obsolete. Electric operation removes the need for hydraulic pipework and other components, and there is no risk for pollution from hydraulic oil. MacRack’s electric motors are controlled by programmable logic controllers and variable frequency drives. The operator is free to move on deck within the cable range of the portable operating unit. When closing the hatch covers, the mechanism lowers the covers and pushes them together to achieve the correct compression and weathertightness of the hatch cover seals. MacRack’s modular configuration saves installation time at shipyard.