CSG Standardised Wellhead Package

GPA designed and commissioned a standardised wellhead skid for the Fairview CSG field in Queensland

GPA designed a new generation of multi-well coal seam gas production and separation facilities for the Fairview field in Queensland.  The design utilised modular build with standard and expandable configurations. The project achieve substantial reduction in engineering, fabrication, and site construction.

The project demonstrated the benefits of an integrated project team (client personnel embedded in GPA’s offices), modular design, fit for purpose design, and a joint emphasis on operability and constructability leading to great feedback from operations, fabricators, and construction personnel.



Above ground midline risers for Santos Big Lake gas field

A new gathering system was installed at Big Lake south of Moomba and it required the installation of six DN300 trunk lines, each with several midline valves and tie-in.

For ease of operation, allowance for future abandonment, and decreased corrosion risk – it is preferable to install these facilities above ground. However, thermal expansion of the pipeline poses a significant design challenge.

The two most common solutions are installing concrete anchor blocks on either end of the mid-line facilities, or introducing flexibility by installing bends. Both of these required high cost and compromise, so another opportunity for innovation existed.

GPA designed a structure which connects the base of the risers at either end of the valve facility. This structure transfers the pipeline’s strong thermal expansion load from one riser to the other, bypassing the more flexible and vulnerable piping in between.


The solution was fabricated entirely off-site. It was less expensive and used less land area than the alternatives.