The beginning of 2007 set a new milestone in Australian pipeline coating application, with APC Socotherm (APCS) completing the coating of Anzon’s Basker-Manta Project offshore gas linepipe.
APCS was subcontracted by Upstream Petroleum in 2006 to undertake the works in early 2007. The project consisted of Dual Layer FBE and Three Layer Polypropylene (3LPP) coatings to linepipe.
APCS was able to draw on the Socotherm Group’s worldwide experience to enable the application of 3LPP in Australia. APCS believes this is the first time 3LPP has been coated in the Australian market.
APCS’s coating plant in Kembla Grange, NSW was constructed and commissioned in 1999, making it the most modern high capacity pipe coating plant in Australia.
3LPP is a three layer system consisting of a primary layer of thermosetting fusion bonded epoxy (FBE) powder that adheres to the heated steel substrate, providing corrosion protection to the linepipe. The secondary layer consists of an adhesive polymer resin that reacts chemically with the primary layer of FBE to create a bonding agent for the topcoat layer. A final layer of polypropylene (PP) bonds with the previously applied adhesive resin, providing mechanical protection to the system. Both the secondary and final layers are applied by side extrusion methods.
Compared to its sister Trikote™ coating of 3HDPE, which is typically used in Australia for onshore applications, 3LPP coating offers a higher service operating temperature of up to 120°C.
The system also provides higher impact and abrasion resistance due to the inherently tough properties of the outer polypropylene layer. The coating is typically applied to DIN 30678 standard.
The Basker Manta Project is situated in the Gippsland Basin region. The 3LPP scope of the project consisted of applying a minimum total coating thickness of 2,500 µm to over 63 km of 219.1 mm diameter linepipe with wall thickness of 12.7 mm and 15.9 mm. Dual layer fusion bonded epoxy was applied to the onshore section of linepipe.
Due to Upstream Petroleum’s stringent linepipe manufacturing requirements for the offshore pipeline, the project required steel to be imported from overseas. APCS conducted a 24-hour bare pipe receipt operation for the client to help minimise potential expensive shipping demurrage costs at the beginning of the contract.
Three layer polypropylene coating is available on pipe sizes from NB80 mm to NB 1,500 mm with pipe lengths ranging from 9.5 m to 18 m.