Custom Designed Shackle Load Cells for Offshore Mooring Tension Application

As well as providing a comprehensive range of standard load cells, LCM Systems has highly experienced in-house design engineers who time and time again have demonstrated their ability to meet both the commercial and technical requirements of clients. For one offshore engineering systems integrator, LCM Systems provided a complete shackle load cell solution designed to match stringent criteria, complete with full American Bureau of Shipping (ABS) traceability.

The enquiry was made by a long-term client of LCM Systems, who had previously bought load pins from LCM to be installed into shackle and pin assemblies already on site. This project was to provide a complete shackle load cell solution for measuring mooring tension but there were some important criteria that needed to be met.

Firstly, the load cell had to be a shackle type, designed to fit into an existing link plate and the pin had to be manufactured from 17-4PH stainless and withstand full submersion to 500psi. Secondly, material and proof load certificates were required for the shackle, with the load pin requiring full traceability to pass inspection by the ABS. Additionally, all cables had to be robust and protected.

The result was the LCM3064 150te subsea submersible D-type shackle load cell that answered all the criteria. The load cell was designed using a GN Rope H11 shackle rated to 150te, with the pin manufactured from 17-4PH stainless steel. It also featured a mating 10m subsea moulded connector cable assembly, protected by heavy duty, steel reinforced hydraulic hose and a special anti-rotation bracket to loop back the hose for the correct cable path. In order to ensure the load cell would fit into the existing assembly, loose spacers were supplied for added flexibility when it was installed into the widely toleranced link plate.

LCM Systems offer a wide range of standard shackle load cells and also have an extensive selection of custom design versions, which could also be used to satisfy other applications. Many of these products are also supplied with LCM Systems’ TR150 handheld battery powered indicator, with built in analogue signal conditioning, digital outputs or wireless telemetry. Customers are also able to specify a particular shackle that they wish to use, including the renowned GN Rope, Crosby and Greenpin and LCM will either supply the complete solution or design a load pin to suit the specified shackle.

Full specifications and details are available on LCM Systems’ website with an interactive 3D PDF model at http://tiny.cc/5o9p7