Plascoat PPA 571 for the Coating of Ductile Iron Pipe (Gothenburg Water and Sewage)
The Gothenburg Water and Sewage works serves about 450,000 inhabitants and industries. Water is taken from the Göta river and after treatment in two plants distributed in a network, 1750 meters in length.
Traditionally cast iron pipes have been used but in 1970 ductile iron pipes were introduced. The soil consists of either rock, glacial clay with a high salt content. Corrosion is a well-known phenomenon and many old pipes have been exchanged over the years, but still there are a considerable number of pipes from the last century in service.
Typically, there have been 300-400 failures with these pipes on the main network every year.
In 1986, however, new pipes were coated in thermoplastics and in the last few years in Plascoat PPA 571. Since this change 80 kms of pipe has been installed and so far there has been no instance of failure or corrosion with these pipes.
As a result of this experience, and of controlled tests by the Swedish Corrosion Institute, Plascoat PPA 571 is now being increasingly used for the coating of ductile iron pipes, fittings and hydrants around the world – including the USA (Seattle).
Pipe Coatings - Seattle
A leading coater in Seattle turned to Plascoat's PPA 571 coating to secure an order from the Seattle Public Utilities for the protection of 19,000 feet of pipes and fittings in the often highly corrosive soils of Terminal 18 redevelopment of Harbour Island.
The project work has not only resulted in the PPA 571 thermoplastic being established as the coating standard for Seattle's water distribution mains, but a flow of orders from across the Pacific Northwest and beyond.
The recent projects have included waste water plants in Snohomish and the Olympus Terrace Sewer District at Mukilteo, both in Washington State, through to baggage racks for Alaska airlines.
Plascoat PPA 571 gains Potable Water and Food Contact Approvals
Plascoat PPA 571 has gained numerous approvals for the coating of potable (drinking) water pipes as follows:
- France - DGS directive and AFNOR XP P 41-250-1/2/3 - Water contact.
- UK - DWI – Committee on chemicals and materials of construction for use in public water supply and swimming pools - Reg. 25(1)(a).
- UK - WRC – Water bylaws scheme BS 6920.
- EU - Directive 90/128/eec Food Contact Plastics
- Germany - EU Rules 89/109/EWG and BGA recommendations for contact with foodstuffs
- Germany - Doc. W272 of DVGW – regarding increase in micro-organisms on material for the drinking water sector.
- Japan - Japanese Food and Sanitation law – food contact.
- Australia - AS/NZS 4020, Products for use in contact with drinking water.
- Belgium - Organoleptic, Toxicological and Bacteriological properties – NBN S-29-001, Drinking Water "Hydrocheck" evaluation methods approved by Belge Aqua
- USA - Meets the requirements of NSF 61 (PPA 571 spray and dip grades - colour currently being reviewed)
PPA 571H has been submitted to independent tests to WIS 4-52-01 and all performance requirements have been met.
In addition, all ingredients used in PPA 571 and Plascoat Polyethylene powders conform to the requirements of FDA or EU Directives and are free of halogens and heavy metals."
Plascoat PPA 571ES for Water Tanks
A leading Italian manufacturer of water tanks and water treatment equipment are one of the latest water treatment companies to switch successfully to Plascoat PPA 571ES.
The company specialises in pioneering technology and has developed and built the latest generation of water softening plants, tanks and accessories fro desalination plants that can be found the world over.
Previously using wet paints, the tanks continually suffered from corrosion problems. However, the introduction of the innovative PPA 571ES green from Plascoat has now given the company an effective long term solution.
"We have been looking for a long-term solution to sea water corrosion and are delighted with the performance of Plascoat PPA 571ES. We have been using it on a number of different applications and our tanks have remained corrosion free" said the Manager.
PPA 571ES offers the advantages of perfect edge and weld coverage, pinhole free coating, hgih chemical resistance - in particular to chlorinated water at a concentration of 28 ppm and excellent resistance to sea water.