Adhesives hold lifeboats together through tests

Edited by the Engineeringtalk editorial team Jan 18, 2007

High-performance structural adhesive enables Norsafe to upgrade lifeboats to the highest safety specifications now required by the Norwegian Oil Industry Association.

Crystic Crestomer Advantage 30, a high performance structural adhesive for large component bonding, has been used by Norsafe to upgrade its GEF-40 (gravity escape free-fall) lifeboats to the highest safety specifications now required by OLF - The Norwegian Oil Industry Association.

Crestomer Advantage 30 is manufactured by the Scott Bader Company as part of a range of technically superior composites products including unsaturated polyester resins, gelcoats, vinyl esters and adhesives etc.

All Norsafe boats and associated equipment are approved in accordance with Solas 1983/96 and subsequent amendments, and EC labelled in accordance with the Marine Equipment Directive.

Their GEF-40 lifeboats have also been successfully tested to withstand launch drops of up to 37.5 metres.

However, during 2005 competitors craft have failed tests from an offshore platform with the boats collapsing when hitting the water from a free-fall drop of only 27 metres.

This was despite these boats having been supplied as approved for a drop of 36 metres.

Investigations concluded that no full-scale drop tests had been performed on the competitor's craft, and a second test also resulted in a similar failure for this manufacturer.

As a result of these structural failures, OLF is advising new criteria for the construction of all free-fall lifeboats used in the North Sea.

Due to these regulations, Norsafe is strengthening the construction of its products, including up to 65 boats already delivered, with the remedial work to be completed by 1st October 2006.

This work involves the incorporation of strengthening beams of Vinylester plus Carbonfibre being bonded with Crestomer Advantage 30 to both the hull and the roof structures.

The work is being undertaken on site, while the boats are held at a 35-degree angle on their launch platforms.

Full scale drop tests on the Norsafe upgraded craft have been successfully carried out at 22, 27, 32 and 35 metres, with very little flexing of the boat and no cracking being found in the Crestomer joints of the reinforcement beams.

Crestomer Advantage 30 adhesive is white and nonsagging with controlled gel and exotherm characteristics particularly suitable for marine applications.

It is based on Scott Bader innovative urethane acrylate technology, exhibiting exceptional impact strength and toughness and useable over a temperature range of 5-30C.

Excellent adhesion and gap filling with a wide range of substrates, combined with minimum surface preparation, low odour plus the practicality of Crestomer Advantage 30 being in 380ml cartridges for hand gun application made it an ideal choice for the work undertaken in the confined and difficult working conditions of an offshore platform lifeboat.

Crystic Crestomer is also available in 25kg kegs and 225kg drums for use with bulk dispensing equipment, covering a range of products specifically designed for different structural applications.

Kjell Soerensen, Vice President - Sales and Marketing for Norsafe comments: "Norsafe is more than satisfied with the performance of the Crestomer Advantage 30, which has proven to work as specified".

"As all upgrading is being carried out offshore within a very strict time schedule, it was of great importance that the bonding material fulfilled all the technical requirements, including providing all the required flexibility during use".

"Crestomer Advantage 30 has shown to be the best solution for this project".

"We would also like to thank Scott Bader Scandinavia for excellent service during the project".

The Norsafe company manufactures a range of rescue craft including both conventional and free-fall launched lifeboats as well as davits, designed for the rapid evacuation in emergency situations of ships and offshore installations.

Boat structures are robust enough to withstand high winds, powerful waves, extreme weather and even free-fall launch impact stresses and consequential total immersion conditions.

Up to 90 passengers can be carried safely in enclosed cabins, while securely strapped to anatomically shaped seats.

The boats can also be fitted with water spray and compressed air systems for protection against fire.