Mooring

Lean Installation of Deepwater Moorings

A 'Lean Installation' approach to deepwater line deployment proposed by First Subsea takes as its starting point the ability to be make up connections quicker offshore and thus reduce mooring line deployment time.

Benefits of Lean Installation of fibre rope mooring lines include:

• Shorter mooring campaigns using a wider variety of installation vessels than current deepwater mooring lines,

• Improved quality of the mooring line connection both mechanically through connector design and improved splicing, and

• Increasing the connector make up options to make line deployment easier for fibre rope to fibre rope (R2R), fibre rope to wire rope (R2W), and fibre rope to chain (R2C) connections.

 Traditional vs Lean Installation

From a deployment perspective the primary difference between traditional H-link connectors and the new connectors is the approach to its make-up.

• H-link connector

H-link connectors involve connecting the large spliced eyes at the rope ends, during rope deployment offshore. In some cases this can be a very time-consuming activity as the connector, thimble, spliced rope eye are firstly aligned together and then held in place whilst the load bearing pin is hammered into position.

• LankoFirst connector

For the new LankoFirst fibre rope connector, on the other hand, there are no soft eye splices and no loose thimbles. The end termination is an integral part of the rope rather than an external addition. This is achieved by splicing a sub-connector element into the rope end during rope manufacture.  The design of the sub-connector allows for smaller sub rope splices that are closer to 100% splice efficiency than larger splices. Moreover the splice quality is better as the sub-connector is spliced in the factory, without the risk of damaging the fibre.

LankoFirst Deployment

Lean Installation not only applies to the way the rope is connected offshore. It also applies to deployment of the rope-rope and rope-chain connections offshore. Three connections are possible: clam for rope-rope, link for rope-chain and rope-rope, and snap for rope-rope. In each case the connector elements are integrated within the rope ends during rope manufacture. And each conforms to a 'lean installation' approach to mooring by making the connection simpler, quicker, better and safer offshore.

 The Lankofirst Link Connector showing Lean Installation

Continual Innovation in Deepwater Mooring

The LankoFirst fibre connector is the latest development in the continual innovation of deepwater mooring systems. It provides a means of streamlining the make-up and deployment of deepwater mooring lines, but in the bigger picture of global deepwater production its real significance is lies in the opportunity to bring a 'Lean Installation' approach to deepwater mooring.

For more information on 'Lean Installation of Deepwater Mooring Lines contact Brian Green at First Subsea on briang@firstsubsea.com, and download the LankoFirst brochure here

Visit www.otcnet.org. for a copy of the First Subsea OTC 2010 paper:

Deepwater Mooring Systems - Advances in Connector Technology and Implementation Practice, OTC-20920.