Multi-asset mooring inspection

Woodside Energy contracted Welaptega to conduct three 5-yearly Special Periodic Surveys; all due within the same year in the waters of the North West Shelf off the coast of Western Australia.

The solution

Welaptega provided a multi-asset service package to inspect all three assets during the same mobilization. At the end of the three-week campaign an inspection report quantifying the condition of each system was provided, meeting Woodside’s mooring integrity management plan.

Welaptega project managers planned and executed a streamlined scope of work to efficiently conduct three back-to-back mooring inspection programs, saving time and money for the operator. Reliable and quantifiable data was obtained using Welaptega’s optical Chain Measurement System (CMS), Subsea Caliper, and 3D Modelling system (3DM).


In total, 15 mooring chain links were measured in the most high-risk regions, generating 3D models with only 0.1% error tolerance. These results were compared to previous inspection campaigns performed by Welaptega to track rates of corrosion and wear, giving detailed insight into how the mooring system is ageing over time.

This particular project generated cost savings of $300,000 for the client through the reduction of mobilisation costs and improving efficiencies in the assessment project. In providing its services in a back-to-back inspection, there were fewer financial and logistical challenges to overcome.

In addition, the continuity of using Welaptega for past and future inspections provides high quality results, in turn revealing key trends and allowing robust engineering decisions to be made.