US Navy Provide Safer and Stronger Rope Using Honeywell’s Spectra Fibre

The U.S. Navy has selected Honeywell's mooring lines made of Spectra fibre to help ensure the safety of its crews against line failure, reduce overall line weight and improve the longevity of the ropes.

The Navy is procuring the Spectra-based ropes for new ships and to replace existing lines on vessels from Whitehill Manufacturing Corp., based in Chester, Pa.

Whitehill recently developed the new rope using Spectra fibre to further improve the strength, durability and safety of the lines. Spectra fibre claims to have the highest strength-to-weight ratio of any synthetic fibre, including nylon, polyester and aramid, and pound for pound, 10 times stronger than steel, yet light enough to float. It is hydrophobic- meaning it will not absorb moisture or deteriorate in water-making it ideal for marine applications.

"The safety of sailors is the Navy's paramount concern," said Sim Whitehill, president of Whitehill Manufacturing Corp. "As a long-time partner of Honeywell, we knew that Spectra fibre would be the ideal component in creating the new lines. Using Spectra, we were able to make the ropes lighter, more durable and better suited for use in and around water. This helps streamline operations at the pier, while more securely mooring naval vessels."

In the past, injuries caused by breaking or recoiling ropes were of critical concern to the Navy. Traditional nylon or polyester lines tethering destroyers, aircraft carriers and other large ships were snapping under strain, injuring or killing sailors as they recoiled. To protect its crews, the Navy selected a custom-designed four-strand rope produced by Whitehill. This rope was engineered with one strand slightly shorter than the others, causing it to break first when the rope was about to fail, dissipating energy and alerting sailors to clear the premises.

Whitehill's new rope incorporates this short-strand technology with the strength of Spectra fibre. The new Spectra-based rope is 20 percent lighter than an aramid rope of equivalent strength. This enables a number of improvements, such as providing a stronger, lighter line that allows for single-part mooring rather than "doubling up"-going ship to shore twice in an effort to improve line strength-and allowing for a thicker jacket for an added layer of protection. In addition, unlike aramid ropes, Spectra lines float in water. If a sailor drops one, it can be easily spotted and retrieved before it sinks and becomes entangled.

"Spectra fibre is used around the world in a wide array of high- performance customized rope and cordage applications such as that of the Navy," said Barbara McGrath Costain, Spectra global rope marketing manager. "Spectra is also used in police and military ballistic-resistant vests, helmets and armoured vehicles, as well as for heavy marine and offshore applications. We are honoured to work with Whitehill to keep sailors safe and secure with Spectra-based mooring lines."

Spectra fibre is made from ultra-high molecular weight polyethylene that is used in a patented gel-spinning process. The gel-spinning process and subsequent drawing steps also allow Spectra fibre to have a higher melting temperature (150°C or 300°F) than standard polyethylene.

Publication Date: 06/05/2005

WWW Link: http://www.honeywell.com

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