Page 42: of Marine Technology Magazine (April 2013)

Traditionally thought an expensive alternative to tra- ditional steel wire and conventional polyester-based synthetic ropes, offshore ropes and mooring systems made with Dyneema have been making inroads. End users such as ConocoPhillips, Shell and Petrobras are working with systems based on the high-strength, low-weight Þ ber of DSM Dyneema. Coupled with their durability and longevity, these rope systems are increasingly recognized for a variety of performance and user beneÞ ts that ultimately save on the bottom line.DSM DyneemaÕs entry into the offshore industry over 10 years ago met with more troubled waters initially. Manufac- turers and users were slow to latch on to the long term value and investment payback that Dyneema offered, as the higher upfront capital investment proved a disincentive. In addition, Dyneema Þ ber supply was occasionally restricted due to ca- pacity restrictions in the early days of market commercializa- tion.These issues no longer persist today. Today Þ ber is gaining acceptance as a smart choice for the long term, an investment that can pay back on the CAPEX in a few short years. In addi- tion, over the past 10 years DSM has invested signiÞ cantly to boost capacity in its global plants in order to meet the growing year on year demand as well as anticipated market growth. Most recently, Brazilian oil giant Petrobras speciÞ ed Dyneema Þ bers for a complete set of mooring ropes for a semi-submersible mobile offshore drilling unit (MODU). Petrobras speciÞ cally asked for the ropes to be made with SK78 grade of UHMWPE (ultra high molecular weight poly-ethylene) Þ bers from DSM Dyneema for its high strength at low weight properties. SK78 grade Þ ber was developed spe- ciÞ cally for this type of mooring application and although it has a proven track record of success in Asia, U.S. and Eu- ropean waters, the Petrobras order marks the Þ rst time they will be used for MODU mooring in Brazil. SK78 is the only HMPE Þ ber approved by Bureau Veritas and ABS for MODU moorings.Petrobras is expected to use eight mooring ropes made with Dyneema SK78 Þ ber on a MODU in its new Pre-Salt deepwa- ter Þ elds off the South-eastern coast of Brazil, site of one of the largest recent oil discoveries in the Western Hemisphere. ÒPetrobras has chosen to use ropes made with Dyneema over polyester because of the lower weight and greater ease of handling. Polyester ropes with the same mechanical proper- ties weigh around three times as much and are almost twice as thick as ropes made with Dyneema,Ó said Jorn Boesten, Offshore Segment Manager at DSM Dyneema ÒSteel ropes would weigh around seven times more than ropes made with Dyneema. Ropes made with Dyneema will allow Petrobras to moor the MODU more quickly, saving on equipment costs, as well as on support vessels, delivering lower operating costs and a positive return on the investment.Ó Mooring Technology Mooring Ropes Economics of Dyneema-based ropes o shore 42 MTRApril 2013MTR #3 (34-49).indd 42MTR #3 (34-49).indd 424/4/2013 9:25:38 AM4/4/2013 9:25:38 AM