Offshore Construction Specialists (OCS) was contracted by PTSC Offshore Services to perform a feasibility study to convert the Accommodation Crane Work Barge (ACWB) “POS1” into a pipe laying barge employing a S-Lay mode Pipelay system.

The Accommodation Crane Work Barge (ACWB) “PTSC Offshore 1” or “POS1” is a 300-man accommodation barge owned by PTSC Offshore Services. The builder of the POS1 was Jiangsu Ganghua Shipyard Co. Ltd, PRC, then under a different name “Jaya Installer 7” in 2009 and renamed after PTSC took over the ownership. The vessel is classed as XA1 Barge by VR-DnV and is 111.56 metres long x 31.7 metres wide with an overall depth of 7.31 metres, registered under the Vietnamese flag.

The converted pipe lay barge will be designed to allow the POS1 the ability to operate in water depths from 5m to around 100 metres (subject to pipe lay and stability analysis limitations which is dependent on pipe size, water depth, pipe material, pipe coating, pipe tension, winch capacity and stinger configuration.

This feasibility study has been performed to assess suitable pipe lay equipment and prepare proposed pipe lay arrangements based around retaining the existing accommodation and other features relating to its current configuration. Basic pipelay philosophy for the conversion are: