Wear of ropes on mooring fairleads
Large ocean-going vessels such as LNG carriers are moored to piers or jetties by substantial ropes. These ropes pass through a ‘fairlead’ as they leave the vessel to be tied off to a bollard on the pier. The two main classes of fairleads are Panama and roller fairleaders. A variety of ropes are employed over these fairleads, including six strand wire ropes and fibre ropes made from materials including HMPE (high modulus polyethylene), polyester, polypropylene and nylon. Steel wire ropes have recently been partially displaced by synthetic fibre ropes. Whilst more expensive, synthetic ropes are lighter and generally last longer than steel ropes, and thus promise cost effectiveness. Additionally, their light weight means that they are easier to handle which leads to savings on crewing costs; they cause fewer injuries; and, finally, cause less damage to the fairleader surface over which they operate. The paper presents results from a research programme to investigate the performance of wire rope and two types of HMPE fibre rope (with and without chafing protectors) on roller and Panama fairleads, and on a cast nylon material used as a bolt-on Panama liner specifically for use with fibre ropes.
Author(s): I.M.L. Ridge, R.E. Hobbs and S.J. Banfield