January 2023

Bespoke recovery assembly for Subsea7 PLSVs

MDL has designed and manufactured a bespoke Aft Recovery System for Subsea7.

The assembly, consisting of a chute, a removal device for buoyancy modules and a horizontal hang-off system, will be utilised on multiple Subsea7 vessels operating in deepwater.

The complete system will be mountable in different locations on the stern of the vessels, to facilitate safe replacement of lazy wave flexibles fitted with buoyancy modules.

The device is engineered to be fixed to the deck by way of sea-fastening brackets with a bolted connection for quick release.

The system can recover a range of product diameters without overbending the flexible or crushing the buoyancy modules.

The inboard angle of the chute arc extends over 90 degrees to facilitate buoyancy modules manoeuvring without using a crane and it is designed with a dedicated guide rail to support the modules through recovery.

To allow for the suspension of the catenary weight during recovery of a damaged lazy wave, the hang-off clamp is designed to be orientated in a horizontal position.

MDL has previously provided solutions to Subsea7, through design, manufacture, provision and operation of a range of back-deck equipment, including bespoke deliveries of reel drive systems, tensioners, deck radius controllers and turntables to global locations.

In recent years, MDL AME technical team has travelled to Subsea7 vessels to perform 5-yearly maintenance works as well as winch load-cell upgrades in-situ.

James Farquhar, MDL AME Key Account Manager, said:

“I am pleased to see the relationship with Subsea7 continue, from bespoke design and manufacture to providing equipment for specific projects, to more recently asset maintenance and engineering services for their global fleet. This latest delivery draws a full circle, reflecting the complete integrated services we can provide as a single-source partner to our clients.

“As an established Original Equipment Manufacturer, our 23-plus-year expertise of the back-deck also makes us the ideal partner to efficiently perform annual surveys and 5-yearly maintenance programmes on lifting and pulling equipment, including cranes and third-party systems – a growing track record in our trusted services portfolio.”