Australian Pipeline Precommissioning

Australian Pipeline Precommissioning with Flexible Downline

An Australian integrated solutions provider engaged Flint Subsea to support precommissioning operations on a newly installed offshore pipeline system in Northern Australia.

Our client had won a project to provide precomissioning services over a year-long contract with an installation contractor which involved pumping from a vessel, through a flexible downline into a subsea pig launcher. Flint Subsea was involved to provide equipment to mitigate for vessel drift of drive off during operations.

Application

The Flint Subsea Mid Line Weak Link Emergency Quick Disconnect (EQD) was deployed subsea, installed on the end of a flexible downline with a short 20m section going into the pig launcher.

Location and Water Depth

The project occurred off the northwest coast of Australia, with operations in water depths from 130 m to 350 m.

Operating Pressure

Operational pressures reached up to 300 bar to support all precommissioning phases.

Why did the client approach Flint Subsea

Our client had used our equipment extensively in North America, Africa and Europe for the previous 5 years.

The Challenge

There were a couple of challenges with this project. The first was the remoteness of the mobilization location, which created some logistical challenges. The second challenge was that during operations, our client wanted very low tension pin break loads installed. Whilst not a problem during operations, the deployment and recovery loads could be higher and a solution to overcome this problem was required.

Objectives

Deliver a flexible, safe downline system on time to a remote location.
Utilize low tension pin break loads during operations, but facilitate greater loads during deployment and recovery,

Our Approach

To overcome the logistical challenge, Flint Subsea applied our “get the job done” philosophy which included arranging a dedicated hot shot driver to take the equipment over 1500km.

To overcome the installation / recovery load challenge, Flint Subsea were able call upon the fleet of accessories and spares that we hold in stock at our service center.

The Solution

A tension pin override system was installed onto our rental Mid Line EQD. The override system was deployed locked so that the tension pin did not see installation loads. When the unit reaches operating depth, the ROV unlocks the handle to activate the tension pin. When the work is complete and the unit is recovered, the ROV locks the handle again.

Results and Impact

The project was completed successfully with no disconnections during recovery or deployment.

Why choose Flint Subsea

Flint Subsea have a wide range of accessories and tools which can be used to enhance the performance of their standard rental equipment. Doing business with Flint Subsea is easy and we always do our best to ensure that parts are delivered on time and in full to wherever they are required, even when it is 1500km from the nearest large airport.