Pipe Freezing

Pipe freezing gives you a temporary isolation in a live line without draining the system. We apply liquid nitrogen to a section of pipe, draw the heat out of the product inside it until it freezes, and the resulting ice plug holds while you do the work. Nothing is drained, nothing is vented, and nothing has to be refilled and recommissioned afterwards.

Call 1800 468 827 with your pipe size, material and what’s in the line, and we’ll tell you whether it can be frozen.

What is pipe freezing?

It’s a non-intrusive, controlled method of pipeline isolation using liquid nitrogen. The process draws heat out of the product inside the pipe until it drops below its freeze point and forms a solid ice plug inside the line.

Once the freeze is achieved, the plug will withstand very high differential pressures. It’s a reliable isolation, and it lets alterations be completed without a full drain down.

Why freeze instead of draining the system?

Because a break-in can be done without the cost and downtime of draining everything. That’s the whole point of the method.

The savings stack up beyond the outage itself. There’s no venting procedure to arrange, no bulk transfer or storage of fluids, and no loss of expensive liquids like treated water and system inhibitors. On lines carrying contaminated or volatile product it also avoids handling hazardous material, which makes the job safer as well as cheaper.

What is pipe freezing used for?

The common jobs are valve installations, pipe section replacement, equipment isolation, pipe branch terminations, pipe diversions and pipeline abandonment.

A lot of our freezing work is on chilled water and heating hot water systems in commercial buildings, where the ring main can’t come down and there’s no practical isolation valve near the work. If you need a valve cut into a live chilled water riser, freezing is usually the method.

What can be frozen?

We freeze carbon steel, Kunifer, stainless steel, aluminium alloys, ductile and cast iron, nickel alloy and copper based alloys, carrying water, acids, coolants, paints, alcohols, oils, liquid food product, various chemicals and sewage.

If your line isn’t on that list, ring us anyway. The question is usually about the product inside and the access around the pipe rather than the pipe itself.

Freezing, hot tapping or line stopping?

They solve different problems. A hot tap creates a new connection into a live line and leaves a valve behind permanently. Line stopping gives you a temporary isolation using a plug inserted through a fitting. Pipe freezing gives you a temporary isolation with no fitting welded on at all.

Freezing tends to be the answer where you can’t weld on the line, where there’s no room for a fitting, or where the job is short enough that a permanent tapping point isn’t worth installing. If you’re not sure which one your situation calls for, describe the job to us and we’ll tell you which method we’d use and why.

What helps us quote it

With freezing, what is in the line matters more than anything, because the contents have to actually freeze. The rest helps:

• Pipe size and material
• What’s in the line, and at what temperature and pressure
• Whether the product is still flowing, and whether flow can be stopped
• How you get to the pipe. Above ground, in a riser, or buried and needing an excavation
• How long you need the isolation to hold
• Any drawings or photos

Call 1800 468 827 or email [email protected]. If you’re not sure whether freezing suits your line, just give us a call, we’ll ask a few questions and let you know.

Where we work

We operate from depots in Bayswater, Victoria and Currumbin Waters, Queensland, and we have clients in all states and territories of Australia as well as the Pacific Islands and New Zealand. We regularly fly in and out to service our clients, including pipe freezing work in Adelaide and across South Australia.

Freezing work travels well, because the nitrogen comes with us. These are the places we have written up so far:

• Melbourne
• Gippsland
• Sydney
• Newcastle and the Hunter
• Wollongong and the Illawarra
• the Central Coast
• Tamworth and New England
• Broken Hill and far western NSW
• Brisbane
• the Gold Coast
• the Sunshine Coast and Moreton Bay
• Toowoomba and the Darling Downs
• Gladstone and Central Queensland
• Cairns and Far North Queensland
• Adelaide and South Australia
• Kalgoorlie and the Goldfields

Pipe freezing is one of ten live pipeline services we provide. We also offer hot tapping, line stopping, squash offs, live valve insertion, thermowell installation, live leak repair and testing and purging.

Common pipe materials, contents and applications