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Dorman Long Technology
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DLT Chain jacks
DLT Chain jack systems are very similar in principle to our strand jacks systems, and can be used with our standard hydraulic power packs and control systems. Our chain jacks are designed to work with any size of chain and are adjustable to get the maximum usable stroke out of each chain size. Our chain jacks have a fail safe chain anchorage system and are generally mounted onto a support frame which can be base fixed to a steel deck below, anchored against a front post or connected via shackles & slings to and anchorage behind the jack (see DL-CH300/2000 drawing).
We can design and supply chain jacks to any size and configuration required. Our chain jacks can be used for both chain pulling and chain releasing operations and have a controlled load lowering valve fitted to the ram extend port block to provide smooth and controlled releasing of a loaded chain. Typical applications include offshore mooring lines, pipeline pulling systems and heavy lifting systems. The chain jack and power pack can be operated using a fixed control panel on the power pack, or alternatively by use of our DL-M or DL-P40 central control systems. Full synchronisation of multiple chain jacks, load monitoring and data logging are available with the use of our DL-P40 computer control system.

The following video shows the sequence for chain pulling and chain releasing for a typical DLT chain jack: