Superfridge
12-01-2013, 07:36 AM
When ammonia systems have seen a few years and perhaps the insulation or paint wasn't installed/applied particularly well or there has been "on the run" repairs done that for one reason or another the insulation was not replaced and you discover some rusty pipework (on the cold pipes) and you know if you don't do something about it you will have a leak to deal with what products are available that can be applied to steel pipe work that dry or set quickly?
Its a tough ask, a cold pipe that might get hot on a defrost (+30degC to -30degC)is not an easy thing to protect with paint. If the insulation is vapour sealed there should be no rust but I don't think the insulation installers around here know that. Also, because it's at the point of finishing off a job where pipes are painted, corners are cut and some school leaver gets handed a brush and told to "go to it".
Also, what applications do you apply to valves to prevent them from rusting on a plant that is in operation?
We have used BlackGuard rust converter on pipes with variable success and tend to used Petrolatum Tape (Denso) on valves which, so far, seems to be working well.
Its a tough ask, a cold pipe that might get hot on a defrost (+30degC to -30degC)is not an easy thing to protect with paint. If the insulation is vapour sealed there should be no rust but I don't think the insulation installers around here know that. Also, because it's at the point of finishing off a job where pipes are painted, corners are cut and some school leaver gets handed a brush and told to "go to it".
Also, what applications do you apply to valves to prevent them from rusting on a plant that is in operation?
We have used BlackGuard rust converter on pipes with variable success and tend to used Petrolatum Tape (Denso) on valves which, so far, seems to be working well.