One area where composite materials have gained considerable acceptance in the offshore oil industry is topside piping — the miles of piping located on the drilling or production platforms that carry seawater and process water, various chemicals and water for fighting fires. In the last two years, the International Organization of Standards has introduced two new international standards for the use of glass fiber-reinforced plastic (GRP) materials in offshore industries: ISO14692 — "Petroleum and Natural Gas Industries — GRP Piping" and ISO15840 — "Thermosetting Resin Fiberglass Pipe and Fittings to be used for Marine Applications." According to Kevin Schmit of EDO Specialty Plastics (Baton Rouge, La.), the two standards are vastly different yet are positive steps in further development of GRP offshore. "Both standards try to tackle the difficult issues associated with entire GRP systems, not just the pipe and fittings," explains Schmit.
An improvement over predecessor documents, the design methodology takes hoop stress, axial and bending stress into account. And, inspection techniques also are provided. However, fire performance requirements have been left largely unchanged, says Schmit, which puts the onus on pipe manufacturers to conduct dry, hydrocarbon furnace fire testing, a somewhat unrepresentative scenario for an open deck.
Schmit points out that ISO14692 in particular has the potential to break down barriers to GRP, such that the qualification and design methodologies in the document could be carried over into other applications, such as risers, buoyancy modules and composite pipelines. The most critical element for success, he points out, is that piping manufacturers must take responsibility for all aspects of the piping system, including site installation, testing and commissioning "A team effort is needed," he concludes, "with designers, manufacturers and operators who all know what GRP can and cannot do."