DLM Design and Manufacture New Detrenching Grapnel
Dynamic Load Monitoring, specialists in the design and manufacture of Load Cell’s and Cable Working equipment based in Southampton, UK are pleased to announce the design, manufacture and deployment of a new 1.5m penetration Detrenching Grapnel.
The new Detrenching Grapnel has been several months in development by DLM’s Engineers, drawing from many years experience in the Offshore Cable Laying industry. The Detrenching Grapnel is designed to penetrate the seabed to depths of up to 1.5m and will be used for recovering out of service subsea cable previously buried. Currently deployed on a European Cable Ship it has already undergone successful trials and will be used shortly in up coming Detrenching operations.
The new Detrenching Grapnel can be fitted with two 1.5m penetration removeable flukes which are also fitted with shear pins to prevent damage to the grapnel. The shear pin is designed to fail when a load of 15t is seen at the tip of the Detrenching fluke, which provides protection to the Grapnel. When combined with a DLM Running Line Monitor mounted on the deck of the vessel to measure the line tension in the Grapnel tow wire, an increase in the load indicates to the operator that cable has been caught. Conversely a drop in tension would indicate that the shear pin has failed and requires replacement.
Some new features of the 1.5m Detrenching Grapnel include replaceable wear tips fitted to the Grapnel fluke which protects from excessive wear, twin sided operation with the ability to fit two flukes and a compact foldable design for storage and transportation.
Martin Halford Managing Director at DLM commented; “With subsea cable burial depths over the years progressively increasing due to the ability to lay and bury cable at deeper depths, we were frequently seeing the requirements from the Offshore industry to recover cable at depths of 1.5m. For many years 1.1m Detrenching had been the standard and we were able to offer our existing Detrenching Grapnel or Wheeled Detrenching Grapnel, however drawing on our experience in the design of Grapnels and Subsea Cable Laying equipment we were able to completely re-engineer our existing model to meet the new demands of the industry. The new Grapnel will be added into our ever expanding hire fleet and will also be available for purchase in the near future.”