All thermoplastic pipe liners used in gaseous applications are susceptible to the permeation of gas into the annulus between the liner and the carbon steel pipe. Smaller molecules such as hydrogen are more prone to permeation than others, and all molecules tend to permeate at greater relative rates under higher pressure and temperature conditions. Safetyliner™ is an innovative plastic pipe liner that offers an extra level of pipeline protection and is designed to provide a more effective and efficient method of managing the permeated gases that migrate into the annulus.
The Safetyliner™ product offers all of the same lining protection of the Tite Liner® system, but differs in that a series of small grooves exist on the outside of the liner. The grooves in the Safetyliner™ pipe provide a path for any gases that may permeate the liner. These gases are channeled along the grooves to monitoring vents positioned near the pipeline connections. This monitoring and venting can be manually operated or fully automated to keep annular pressure below the level desired to prevent liner integrity problems. United’s thermoplastic pipe lining systems have a remarkable history of leak-free operation, but if the Safetyliner™ system was ever breached, the unobstructed grooves allow quick detection of any possible leak.
Because of the ability to immediately detect any possible leak, the Safetyliner™ product has been used as a cost-effective method to satisfy high-density polyethylene dual containment requirements in the mining industry. The same theory applies in managing permeated gases with the Safetyliner™ product, which provides an unobstructed path for the gas to migrate to monitoring vents placed along the steel pipeline. These individual vents may also be connected to one another to create one continuous path with the actual monitoring stations spaced miles apart. Doing so can allow all permeated gases to be vented at either end of a long pipeline, thereby reducing the operational demands of monitoring the pipeline.
Safetyliner™ provides excellent protection against internal corrosion and abrasion, and it is still far less expensive than stainless steel or other exotic alloy alternatives. The advance design of the Safetyliner™ product has proven especially effective in applications such as CO2, sour gas, 3-phase oil and tailings pipelines.