Pipe Freezing

Pipe Freezing (Cryogenic) for temporary Pipe Isolation has become the Safest, Cheapest & Most effective method allowing Valve Replacement and Pipework Modifications.

Fluid in the system no longer needs to be drained down. Therefore valuable time can be saved and the costly process of refilling and venting can be avoided. Toxic fluids do not have to be drained and stored or at worst disposed of and then replaced.

Direct Liquid Nitrogen Pipe Freezing

Direct Liquid Nitrogen Pipe Freezing is the most common procedure used to establish isolation on a pressurized Pipeline, requiring the application of Liquid Nitrogen to the external surface of the Pipe. This transfer the low-temperature Liquid nitrogen through the pipe reducing the pipe fluid temperature below its freezing point and developing a freeze plug. The technology as described above affords us the ability to control the area of the pipe to be frozen.

Once a plug has formed it is capable of withholding pressure up to 4000 psi and this is maintained to allow pipework modification to be undertaken with confidence. Freeze time is dependent upon many factors. Primarily it is the size of the pipe although system condition and ambient temperature are contributing factors. Once we know the particular of your Application we can predict the actual Freezing time.

The Pipeline Material that can be subjected to Cryogenic temperature include Carbon Steels, Aluminum alloys, Cast Iron, Stainless Steel, Epoxy coated pipes, Nickel alloys, Copper base alloys.

Pipeline fluids that have been crystallized to form an ice plug include:

Fresh water, Glycol solution, Sea water Effluents / Sewage, Produced water, Sludge’s, contaminated water, Alcohol, Crude oil, Bunker C oils, Fuel oils, Methanol, Lubrication oils, various chemical products.

The positive seal provides two distinct advantages:

  • The rubber seals expand 20 mm in range and takes up ovals or build up within the pipeline.
  • The Mechanical Special seal allows new section of pipe to be pressure tested between the stops

POWER STOP is a unique patented equipment and process of our PTS (SA) Ltd. UK.