January 2023

MDL upgraded tensioner drives SURF replacement

An MDL portable spread featuring the company's newest tensioner has completed a flexible pipeline replacement scope in the UK North Sea.

The project consisted of the installation of an Electro-Hydraulic Cable (EHC) and four flexible jumpers off an Offshore Support Vessel.

The 9.2m and 11.4m reels were handled using MDL’s Generation 2 Reel Drive System integrated with the company’s 4-track tensioner, the TTS-4/180 unit.

The system used on the project was the newest addition to MDL’s fleet – an upgraded iteration of the company’s patented MDL TTS-4/140 Series Tensioner design, featuring an extended track contact length of 4.074m, together with increased squeeze capability of 44.7-tonne per meter per track, which allows for an increased line pull capability of 51-tonne and an improved coefficient of friction (CoF) of 0.07.

A key feature of all MDL tensioners is the Failsafe Grip System, ensuring consistent hold on the product at all stages, even in case of power loss, preventing unwanted release of product.

Thanks to its cylindrical design, the tensioner opens a single track in horizontal mode – as deployed on this project – and two tracks when deployed in vertical mode for accepting and releasing the product.

Like all other equipment in MDL’s flexlay solutions fleet, the tensioner is road-transportable and can be deployed on any vessel of opportunity, mobilised in a single crane lift.

For this project, MDL also supplied a set of pads specifically to handle the small diameter umbilical (91.3mm)

While the Generation 2 RDS facilitated efficient deployment of multiple reels, thanks to the complete automation, including towers’ skidding and clamping onto the tracks - resulting in moving between reels 4x quicker than market standard.

Chris Reid, Vice President - Sales at MDL, said:

“It’s always a pleasure to receive repeat orders from clients, but more importantly, these lead to cost efficiencies on subsequent projects. In this case, we had worked with the client on the same vessel before. Our Generation 2 RDS was deployed in the same location on deck, which streamlined the pre-project engineering requirements.

“By holding open and honest communications, we can jointly identify opportunities for such efficiency improvements – where we can use a single mobilisation for a few back-to-back projects, for example - all in an effort to deliver maximum value to the operators, in the most responsible way.”