Remote controlled subsea hot tapping machine

Friday, May 04, 2012

Stavanger pipeline equipment company T.D. Williamson has launched a new subsea "hot tapping" machine, which can make connections to existing pipelines without interrupting flow through them.

The machine is supported by a diving support vessel or platform.

The machine has been field tested at an undisclosed project in 91 metres of water, adding a 16 inch tap to a 28 inch gas pipeline.

Subsea hot tapping might be required to add in tie-ins (production lines from a new well), pipeline repair, insertion of instrumentation, chemical injection or providing access for temporary isolation tools.

The process includes installing the hot tap assembly, performing the tap and recovering the hot tap machine.

Until now, the process could only be performed with divers, T D Williamson says. Now it can be done by remote control.

As well as being dangerous, diver operations are limited to 300 meters (984 feet) of water depth, and many subsea equipment is deeper than this.

The remote control operation can also be done more precisely than a diver can do it.

You can monitor what is going on from a laptop computer.

'The most critical part of the hot tapping process is the point at which the drill penetrates the pipe, which has now been rendered diverless by the Subsea 1200RC Tapping Machine," says Mike Benjamin, Vice President, Offshore Pipeline Solutions for TDW.

If there is no pre-installed "tee" you will still need divers to install and remove the machine, but the work can still be remote controlled.

The surface control is made via a stationary remote operated vehicle which is connected to the tapping machine.