Sea Technology

JUL 2013

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

Issue link:

Contents of this Issue


Page 14 of 71

Application-Specifc HMPE Synthetic Rope Unitrex XS Max Wear Rope Lowers RSNs Deep Into Pacifc for OOI By Bill Putnam T wenty years ago, oceanographic professor, James Delable to observe underwater volcanoes, migrating fsh, major aney, now at the University of Washington (UW), walked earthquakes, powerful currents and blooms of microscopic into a bar in San Francisco, California, and complained to life—all observations that were not possible previously. a friend about the diffculty of gathering data in the deep ocean. That conversation was the impetus for a gameUnitrex Rope for RSNs changing project called the Ocean Observatories Initiative L-3 MariPro had many options for the rope it chose to (OOI), according to National Public Radio. lower the RSNs into the deep waters of the Pacifc Ocean. The U.S. National Science Foundation (NSF) hired UW Ultimately, a high-modulus polyethylene (HMPE) synthetic to oversee the development of a networked system to rope called Unitrex XS Max Wear, by Yale Cordage (Saco, study the ocean and seafoor, Maine), was chosen, the benwhich included the laying of efts of which include a light 560 miles of fber-optic cable weight, superior break strength connected to video cameras, and excellent performance on seismic monitors and stratesingle-drum winch lines. It outgically placed regional scale performed traditional products nodes (RSNs) along the Juan like steel-wire rope and other de Fuca Plate off the coast of synthetic alternatives. Pacifc City, Washington. RSNs are terminal points that distribLightweight Synthetics' ute power and bandwidth (10 Advantages in Deeper Waters gigabits per second on each HMPE synthetics like Unitrex port) to areas where there are tend to have fewer limitations in sensor networks. deep water than steel-wire rope. Because some of the most Deck crews can work faster durPreparing RSN secondary cables for installation on the seaadvanced and expensive teching deployment and recovery on foor. (Photo Credit: University of Washington) nology was used in this project rope systems and winch lines to collect data, UW paid close with reduced weight. Some sinattention to how the multimillion-dollar RSNs were lowered gle-drum winches can add more than 80,000 pounds to a from a cable-laying ship into the ocean. The deployment of vessel. When the weight of a heavy drum combines with these RSNs into deep waters of the Southern Hydrate Ridge tonnage from steel-wire cable, crews are forced to use shortand Axial Seamount was contracted out to L-3 MariPro Inc. range vessels. Synthetics, on the other hand, greatly reduce (Goleta, California). the weight aboard a vessel, enabling crews to operate large The cable installation took place in 2011, and primary vessels in depths of 1,000 to 3,000 meters—essential to RSNs were installed in 2012 in water depths ranging from oceanographers studying the seafoor. In the case of OOI, 25 to 600 meters. The RSNs lowered to the seafoor have scientists have reached depths of 600 meters, but have the created an underwater observatory that feeds information option to venture into greater depths when additional infraon events happening in the ocean and seafoor to landstructure is deployed in 2014. based scientists, engineers, educators and the public in real Break Strength. Unitrex offers the same break strength as time. Delaney describes it as an "undersea network deits steel-cable counterparts of the same diameter—an imporsigned to funnel a fre hose of open-source, real-time data tant factor when deploying RSNs or recovering heavy-duty to the Internet, 24/7." Researchers and the public are now equipment in deep water. Deck crews have the beneft of July 2013 / st 15

Articles in this issue

Links on this page

Archives of this issue

view archives of Sea Technology - JUL 2013