Coating for welded Aluminized Steel Charge Air Cooler Pipe?

[wallybanger]

I am currently in the process of designing a charge air cooler pipe for a class 8 truck and I need some advice on which finish to spec for the part.

The pipe it's self will be ASTM A787 Type 1 aluminized steel but it will be welded to a ASTM A513 steel fitting. Typically the aluminized steel pipe wouldn't be welded and would be sufficiently corrosion resistant without additional coating but in this case I believe additional protection will be required.

The customer suggested an e-coat, which I was unfamiliar with, but now I'm getting the impression that an e-coat would only be a primer and not a top coat. Is that correct? An e-coat would be a good choice because it would coat the entire part, inside and out with a very thin layer of paint (0.02mm to 0.03mm, as I understand). Is it common to spec only an e-coat to finish a part? Would a colour be specified?

Any info or suggestions would be appreciated.

Thanks,
Mike

 

[CoryPad]

E-coat is common as the only coating on a part for automotive applications that are underhood/underbody with limited exposure to ultraviolet radiation. Black is by far the most common color, but others are possible.

 

[wallybanger]

OK, that's good to know, thanks. So would it be appropriate to spec the finish on the drawings as "Finish: E-Coat, Black, 0.02-0.03 THK."?

 

[CoryPad]

Sure