Eradicating external pipe corrosion

Numerous attempts have been made over the past few decades to protect piping systems from external corrosion at the pipe support points. Metal wear plates that cradle a pipe from beneath are either fully-welded or tack-welded to a pipe at the contact regions to protect it from friction, and they can be an effective solution.

While these metallic saddles do protect the pipe’s paint coating, they do not stop corrosion, but rather promote it: you still have metal-to-metal contact, after all. Also, the installation process requires line shutdown, welding permits, and experienced welders to conduct the work. This would halt production for the duration of the procedure. Such metallic wear pads can also become a safety hazard if moisture is trapped in crevices between pad and pipe, causing the formation of hidden corrosion cells that are hard to detect.

Metal round bars have also been used to raise pipes above their supports to promote airflow. However, such bars would scuff the coating and also point-load the pipe and cause increased stress at the points of contact, not to mention promote corrosion, since there is still metal-to-metal contact. Their plastic counterparts sometimes deteriorate and break off, or simply cause the same point-loading and associated damage.

Rubber, neoprene, and PTFE flat sheets or wraps are sometimes placed under or are wrapped around a pipe at contact regions to isolate it from its supporting structures. However, these sheets and wraps often slide off, fall off, or are torn apart due to high friction forces, thus exposing the pipe to the elements again. Ultimately, they all lead to corrosion.

Most of these solutions, including traditional fibre-reinforced plastic (FRP) wear pads that cradle a pipe and use epoxy to be fastened to pipes, usually require special inspection procedures to verify their effectiveness over time. Inspection devices and processes, including X-ray, radiography, ultrasonic spot readings, etc., are costly. Lifting pipes and recoating them at these weakening points is even more costly.

An innovative solution

The RedLineIPS SmartPad System is Cogbill Construction’s all-composite pipe support, with a patent pending, and is designed from the ground up to protect above-ground piping systems in the petrochemical and LNG industries from external corrosion under pipe support (CUPS) points. By utilising a unique composite strapping system, there is no requirement for epoxy or welding to be installed. It installs, can be removed, and then reinstalled in seconds. This allows inspectors to perform routine visual inspections for corrosion, quickly and at a minimal cost.

The FRP SmartPad cradles a pipe from beneath and raises it above its supporting structure …

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