May 2022

Portable tensioner enables GoM deepwater lay

MDL has completed two back-to-back flex-lay projects in the Gulf of Mexico for Oceaneering International.

Both scopes covered recovery and installation of flexible jumpers using the MDL TTS-4/375 Series Tensioner mobilised on board the Harvey Blue Sea.

With the first 15” jumper wet-parked subsea, the tensioner was used to firstly recover the flexible onto the empty installation reel mobilised with an MDL-manufactured reel drive system, for inspection and preparation for installation in-field. The jumper was then deployed in a reverse manner, utilising the reel drive system, tensioner and overboarding chute.

Following the installation, the vessel returned to port to mobilise the reel with a 16.5” jumper for the second project in a separate field, installed using the same spread.

Featuring a 5.5m track contact length, the TTS-4/375 Series Tensioner is the largest unit in MDL’s portable fleet and the most capable road-transportable tensioner above 60Te pulling capacity on the market - offering up to 68Te/m/track squeeze and up to 150Te line pull.

On both projects the tensioner worked alongside an 800-tonne electric Reel Drive System, designed bespoke for Oceaneering and delivered by MDL in 2017. The RDS, based on MDL’s unique Generation 3 RDS concept, can handle reels up to 14m diameter and skid fully-loaded reels up to 500Te in weight.

The application of this highly-capable portable spread allowed the deep-water installation of the product without the requirement for a specialist lay vessel.

Stephen Allan, Senior Manager at Oceaneering, said:

“With moving schedules these two projects were fast-tracked, which meant that we needed to find a suitable installation solution in a short timeframe. MDL provided a prompt response, with quick equipment turnaround and identifying the fastest transit options to get it to the Gulf of Mexico.

“They also provided expert support on both projects from start to finish, and I would not hesitate to work with MDL again in the future.”

Dave Gardiner, MDL VP Global, said:

“We pride ourselves on solving our customers’ challenges to allow them to progress with their campaigns, on schedule and to budget. These two projects fitted the brief perfectly.

“Our market-leading equipment fleet was the game changer here, making a challenging deep-water installation possible without the need for a specialist construction vessel. Additionally, the agility of our team resulted in a fast-track response across the two continents, despite ongoing limitations posed by the pandemic.

“Since either scope consisted of only one reel of product, using our portable equipment allowed deployment of a locally available vessel. The scheduling of these scopes in immediate succession delivered benefits to the project teams through single mob and demob of the lay spread.”

The tensioner has now moved to a storage facility in Morgan City with immediate availability.