Trelleborg, Sweden -- Trelleborg Offshore is supplying diving-bell manufacturer Unique Systems llc with polyurethane syntactic foam insulation to protect divers from the cold experienced in diving bells at subsea depths down to 300 metres.
Unique System's diving bell is designed as a submersible decompression chamber for a three-man saturation diving team. The bell transports divers from a ship's live-in hyperbaric chamber down to working depths that have typical sea temperatures of between 9 deg and 20 deg C, a February statement from Trelleborg said. Typical tasks for such vessels include repair, maintenance and inspection of pipelines.
Shane Julias, design engineer for Unique Systems llc, said that compared to problems Unique has experienced with unpredictability and water ingress in previous insulation systems, Trelleborg's PU-based foam has a high impact resistance and is totally impervious to water ingress under pressure.
"Trelleborg uses its Trident Insulation system which is based on BASF's ZEROHg glass syntactic polyurethane technology, in a one-pour, one-lift foam application," said James Vultaggio, product group manager, Trelleborg Offshore, Houston. According to Vultaggio, the application technique ensures no insulation interface joints for complete integrity and eliminates water ingress into the foam that could affect thermal properties.
In total, around 600 kg of foam is poured around the shell of the carbon-steel diving bell during the insulation process, the statement said, adding that this will be the first diving bell insulated with glass syntactic PU foam.
Trelleborg Offshore is a unit of Trelleborg's Engineered Systems division, based in Trelleborg, Sweden. (RD)