The Detrenching Grapnel is manufactured from high tensile steel, suitable for withstanding the harsh offshore environments. The structure and material of the grapnel is tested using finite element analysis which is performed during the design phase. This simulates the various stresses and strains acting on the grapnel in a variety of different seabed conditions and allowed for optimisation of the design.
The Grapnel itself is scissor shaped at one end, which is designed to break the surface of the seabed and fitted with stabilising bars at the other end, to assist its dynamics and balance in the water column, while also for use in the seabed. In addition, there is an option to fit two Tynes if required either side of the grapnel, Tynes are removable and fitted with wear tips at the end, prolonging Tyne life.
The Detrenching grapnel has been designed to withstand tow tensions of up to 15t. It has a built-in shear pin rated to a breaking load of 15t which shears and protects the tow line and the Tyne if tension is exceeded beyond this point.