This is one Big Winch The RAstar 3200 Class tug Monterrey was delivered to the owners Servicios Mar�timos de Baja California, S. de R.L de C.V. of Mexico by the builders Union Naval Valencia (UNV) of Valencia, Spain. The boat is the first of four designed to work at the Costa Azul LNG terminal on the northwest coast of Mexico, at a terminal exposed to fully developed Pacific swells. The basic requirements for the tug design stipulated that the tug and its winch must be able to sustain a line pull of 75 tons throughout the entire terminal approach in a +2 m significant swell. The resulting winch is massive, powerful and accordingly, it dominated every aspect of the vessel design.
cooperation among design, owner and supplier are more pressing than ever. "Today, we are light years ahead from an innovation standpoint," said Dennis Sherman, technical sales manager, offshore, Samson. "To understand the product, its limitations and benefits, and the task at hand, then engineering the rope to fit that particular application is what sets some ahead of the pack." Samson is no stranger to rope innovation, over the years logging a number of firsts, including the first synthetic rope to exceed 3.3 million pounds in breaking strength, a line of products that provide higher coeffciency of friction for better grip, a reduced-recoil rope, and a fire-resistant towing pendant. From early on in the development of synthetic fiber rope, "as we started to understand properties of the product, its limitations and benefits, we started to manipulate construction and fiber content to tailor products more specifically to applications," Sherman said. A prime example of this is Samson's expansion in the offshore market. Samson, which uses DSM Dyneema fiber for its ropes, and according to Sherman, are Dyneema's largest customer, have made a $10 million investment in its offshore capabilities, including an expansion of its Lafayette, La., facility. Samson and others are making inroads to the offshore market with a product that provides the same strength as steel lines, but at a fraction of the weight. The weight savings, particularly on deepwater projects where the line length increases dramatically, in itself helps to increase the overall efficiency of the winch, allowing a smaller winch to be specified based solely on the weight of the load, and not the additional weight of wire rope, and the fact that these ropes are neutrally buoyant. Samson continues to innovate, developing its patented DPXTM technology, whereby it is able to increase the rope's grip in applications such as those using traction winches. "DPXTM does not add strength, it manipulates the surface coefficient friction, basically doubling it," Sherman said. A good example of this is Samson's roll on the recent Shell Perdido Spar Project for subsea-tree deployment, where it supplied the unit's Logan traction winch with Quantum-12 (60 mm x 9500 ft.), a winch specifically designed around synthetic rope, according to Sherman. While fiber manufacturer DSM Dyneema still counts traditional maritime applications as its biggest business, the offshore market is growing fast, according to Jorn
August 2009
Boesten, segment manager, offshore for DSM Dyneema, who said that the offshore market has been a bit slower to adopt synthetic rope technology because of the factors of experience, trust and cost. But barriers are coming down rapidly, however, as evolving deepwater applications demand new solutions, as ropes grow much longer, and much heavier. "After about 1500 meters, the synthetic rope option becomes much more comparable with wire in terms of cost," said Boesten. An example of how synthetic rope excelled over wire rope was when China Offshore Oil Engineering Corporation (COOEC) needed a lifting sling for a unique offshore jacket installation in its offshore oil and natural
gas fields in the South China Sea. All of those installations relied on the use of lifting slings made with steel wire. They were strong, but wire slings are also very heavier in comparison to synthetic fiber. In September 2008, when faced with the challenge of installing a 16,213 metric ton jacket measuring 75 x 75m and over 213m high at the Pu Yan natural gas field, COOEC opted for four lifting slings made with Dyneema and manufactured by Samson. The four slings were made with Samson's DPXTM fiber, a patented blend of polyester and lightweight, high-strength Dyneema. Mr. Hi Huai Liang, Technical Manager of Offshore Installation for COOEC says, "Compared with steel wire
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