Our Products At Work in the Field

FormaShield® System: External Corrosion & Leaks

December 13, 2017

Project Overview
A 14" natural gas pipeline had external corrosion and two pinhole leaks with a pit depth of 4 to 6 mm. The general corrosion was 300 mm long x 350 mm circumferential on the pipeline. This repair was a Class 4 location with a nominal wall thickness of 9.53 mm and API Grade X-60 (60,000 SMYS). The operating pressure was 300 PSI and the system design pressure was 1,350 PSI. The ambient temperature was 26°C.  

Repair Solution
A two-year design life repair was engineered in accordance to the ISO 24817 standard using the FormaShield system with 36 layers and a repair zone of 505.8 mm to encapsulate half of the flange. This repair will allow the pipe to continue to operate safely until the customer can change the damaged section of the pipe in the upcoming months.

The repair area was water-abrasive blasted to achieve a satisfactory anchor pattern and wiped clean with acetone. EP400 was applied as a filler material at the corrosion points and pinhole leaks. A mold was used to create a smooth transition and be able to encapsulate the flange using the FormaShield system. PPR epoxy coating was applied to the entire repair zone and the FormaShield system was applied using the spiral method with a 50 percent overlap. A total of 36 layers were applied to encapsulate the flange. The repair was constricted, perforated and cured overnight. The next morning, the constrictor wrap was removed and a topcoat was applied. Upon re-pressurization, no leaks were detected, making this a successful repair.

FormaShield_Corrosion and Leak_Malaysia_Repair ZoneFormaShield_Corrosion and Leak_Malaysia_PPR EpoxyFormaShield_Corrosion and Leaks_Malaysia_InstallationFormaShield_Corrosion and Leaks_Malaysia_36 LayersFormaShield_Corrosion and Leaks_Malaysia_Install and Topcoat