Back and Firth

Abnormal Load Engineering (ALE), working for Heerema at the Greenland Road facility in Hartlepool in the UK, has completed a range of specialized transport jobs for the Nexen Buzzard Field Development. The company was contracted to transport and assemble the various pieces of a new oil rig to work at the site of the newly discovered oil.

The Buzzard Field Development is one of the largest North Sea oil reserves and is located in the Outer Moray Firth, central North Sea, north east of Aberdeen, UK.

Fabrication work on the project began in February 2004 and was completed with the load out of the 11,300 tonne utilities deck onto a barge earlier this year.

Prior to mobilising the equipment to site, method statements and engineering calculations were prepared and submitted to meet both the client's and the independent Marine Warranty Surveyor's requirements.

The utilities deck was constructed at the Greenland Road fabrication facility in Hartlepool. The module was assembled from a series of smaller panel units, which were delivered by ALE into the main fabrication shop from smaller satellite fabrication shops. Some of these panels were moved a distance of more than 1.5 km from their fabrication areas to the erection site.

The part completed utilities deck was moved out of the main fabrication shop and positioned between the shop and an adjacent shed outside the site boundary. Oversized items also delivered to site were the rig's crane and its back mast, crane pedestal and the waste heat recovery unit (WHRU) among others, for fitting to the utilities deck.

ALE was required to transport a variety of structures, weighing up to 600 tonnes, for the rig, using 36 axle lines of self propelled modular transporter (SPMT).

A 700 tonne living quarters module and a 900 tonne sulphate removal package were moved and installed on the barge using 48 axle lines of SPMT.

A carousel had to be moved across site and installed on the barge before the largest section, the 11,300 tonne utilities deck, was installed. Both these sections were transported to the barge on 420 axle lines of SPMT.

The company was also responsible for barge management operations throughout, which included mooring and ballasting of the barge during load out.

All works were completed without incident or injury, ALE said.

The Buzzard development will consist of three bridge-linked steel platforms supporting facilities for drilling, production, utilities and accommodation, respectively. The facilities include two subsea water injection manifolds located 2 km from the platform. The crude oil will be transported to the mainland via a pipeline tie-in to the nearby Forties Pipeline System. The natural gas will flow to market via the Frigg Pipeline System.

Once positioned on the barge and sea-fastened, the utilities deck was ready for the journey to its final destination by sea to the Buzzard Field Development. •