Pohokura Gas Field Maintenance Programme
The partners in the near-shore Pohokura gas field north of New Plymouth – operator Shell Exploration NZ, Todd Energy and Austrian company OMV – first started thinking about a major maintenance programme for the field’s offshore production platform about two years ago.
“Fitzroy provided key specialists who were integrated early on into the Worley Parsons engineering team to assist with the detailed planning and design for the project, working on activities such as ensuring safe platform access,” says Fitzroy General Manager Maintenance Shane Coleman.
Fitzroy Engineering is now heavily involved is major aspects of the refit programme including equipment repair, general maintenance and repairs, ultra high pressure water blasting, welding, painting and some special structural steel contracts.
One early component that Fitzroy and Wells Instrument & Electrical were involved in was the fabrication of a special integration stair tower to connect the offshore production platform to the jack-up rig Ensco 107 once it left Port Taranaki and was moored next to the platform off Motunui.
“The team also had to complete additional strengthening to the Ensco rig while it was in port for attaching the stair tower and this required significant work within the rig’s hull. In addition, there was the testing and installing of the stair tower before the rig was towed north to provide a work base for the project.”
The tower, designed by Worley Parsons, weighing over 35 tonnes and built in six weeks, is now providing direct access from the rig to the two decks of the production platform. It is also providing the electrical power and water links from the rig and a ducted hot-air flow to help manage the painting work. As well, it also features a fireproof mesh face for additional safety.
For this project Fitzroy has initiated the use of new scaffolding technology; the innovative QuikDeck system, a first for the New Zealand offshore industry.
“This system has enabled the project to reduce the time needed for building access around the platform by over 50 per cent and at the same time reduce the number of scaffolders required on the platform. The system also provides an ideal barrier to allow work to be accomplished above and below at the same time.
“Most importantly, the design includes a total containment solution to prevent any discharge or waste going into the water – a critical environmental ‘goal zero’ objective for the project,” Shane adds.
“We have a large multi-disciplined team of over 50 people on board, including construction engineers, safety advisors, scaffolders, riggers, abseilers, UHP water blast operators, industrial coaters, welders, welding inspectors and mechanical trades people.
“The project challenge has been, and still is, the need to compress a large amount of simultaneous work on several fronts within a 100 day window on a small platform,” he says.
“And there has been, and still is, excellent levels of collaboration between the various teams involved, providing a great blueprint for working together again in the future,” Shane concludes.