BRIS
Civil/Environmental
- Mar 12, 2003
- 525
We are designing a major pipeline over steep terrain supplying raw water for irrigation- The majority of the pipeline is ductile iron but because of high pressures (pressures over 25 bar in valley sections) some short lengths will be steel - Diameters are 800mm to 1400 mm -
Steel pipe is not my field of experience but I have to prepare a specification for the corrosion protection system.
I have no corrosivity data other than the site is in a limestone area and Ph is above 8.0.
Because of the rough terrain and difficult access I am proposing a polyurethane coating and lining rather than epoxy coating and cement mortar lining. I understand polyurethane is more flexible and resistant to impact damage/poor handling.
Also because of the difficult access and remote location we want to avoid the provision of cathodic protection. will a 3 layer polyurethane system give adequate (50 year) life without cathodic protection.
The obvious reply is to do the job properly - consult a specialist - undertake resistivity surveys and chemical analyses and design the system - but we now don't have time - I need to produce a specification by the end of the week.
Any advice on the suitability of polyurethane coatings and their advantages welcome
Steel pipe is not my field of experience but I have to prepare a specification for the corrosion protection system.
I have no corrosivity data other than the site is in a limestone area and Ph is above 8.0.
Because of the rough terrain and difficult access I am proposing a polyurethane coating and lining rather than epoxy coating and cement mortar lining. I understand polyurethane is more flexible and resistant to impact damage/poor handling.
Also because of the difficult access and remote location we want to avoid the provision of cathodic protection. will a 3 layer polyurethane system give adequate (50 year) life without cathodic protection.
The obvious reply is to do the job properly - consult a specialist - undertake resistivity surveys and chemical analyses and design the system - but we now don't have time - I need to produce a specification by the end of the week.
Any advice on the suitability of polyurethane coatings and their advantages welcome