Wheeled Horizontal Lay System

With Brazil gearing up for a large-scale decommissioning programme, a local offshore contractor saw an opportunity to carry out the SURF recovery operations in a cost-efficient way: using a modular spread on a vessel of opportunity. However, there were no portable systems in the market - neither in Brazil nor globally - that could handle the required recovery loads. They turned to MDL with this challenge.

MDL used its portable Horizontal Lay System as the base case - already proven as a compact package for safe and efficient recovery of SURF with buoyancy modules. However, engineering studies with the client's product specifications highlighted limitations on handling the recovered pipes over a chute. Due to the friction between the flexible and the chute, the system's recovery capacity was dramatically reduced - even when using a high line pull-capacity tensioner. The solution to reduce friction was to replace the chute with a wheel.

By incorporating a wheel into the design, the HLS recovery capacity increased to match the tensioner's capacity without additional space requirements or weight from additional steel structures. The 2-point contact on the product results in reduced MBR requirements, opening up the OD window for wider application. The system incorporates a range of features facilitating recovery of various lengths and diameters of products, including: an integrated hang-off for handling end fittings; davits for overhead handling of products; integrated work platform for over the side or moonpool works and an adjustable wheel position to accommodate various product diameters. The WHLS keeps true to the base HLS design, as the complete package is portable, compact, applicable on vessels of opportunity - in summary, a cost-effective way to kit-out a locally-available vessel to handle high loads and tackle recovery projects.