Replacing Electrodeposited Zinc with Phosphate Coating
Replacing Electrodeposited Zinc with Phosphate Coating
(OP)
We are investigating replacing our Electrodeposited Zinc plated nuts and bolts with Phosphate + Oil due to the following reasons. Can someone please verify if these are true.
1)Phosphating is more cost effective? True or False?
2)Electrodeposited nuts and bolts will have a section on the part where there is no plating (the area they are hung)?
True or False?
3)Electrodeposited nuts and bolts are easily scratched and therefore will lose their coating protection whereas Phosphating chemcially alters the outer skin to provide improved protection. True or False?
Specifically, we have SC4, Type 1 and SC2, Type 1 Electrodeposited Zinc parts. What is the equivalent Phosphate Grade: OD, Type I?
Thanks in advance!
1)Phosphating is more cost effective? True or False?
2)Electrodeposited nuts and bolts will have a section on the part where there is no plating (the area they are hung)?
True or False?
3)Electrodeposited nuts and bolts are easily scratched and therefore will lose their coating protection whereas Phosphating chemcially alters the outer skin to provide improved protection. True or False?
Specifically, we have SC4, Type 1 and SC2, Type 1 Electrodeposited Zinc parts. What is the equivalent Phosphate Grade: OD, Type I?
Thanks in advance!





RE: Replacing Electrodeposited Zinc with Phosphate Coating
2) False
3) False
There is no phosphate coating that can provide equivalent corrosion protection to SC2 or SC4. If you want a better coating, go for multilayer zinc-rich coatings like those from Magni, Doerken or Atotech.
RE: Replacing Electrodeposited Zinc with Phosphate Coating
For Phosphating as per ASTM 1137 Grade I it will achieve 168 hrs.
So I'm confused about your last sentence.
RE: Replacing Electrodeposited Zinc with Phosphate Coating
RE: Replacing Electrodeposited Zinc with Phosphate Coating
KENAT,
Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Replacing Electrodeposited Zinc with Phosphate Coating
Does anybody know if Type I and II require under-oversizing of the threads? I know the Type OD does not.
RE: Replacing Electrodeposited Zinc with Phosphate Coating
RE: Replacing Electrodeposited Zinc with Phosphate Coating
RE: Replacing Electrodeposited Zinc with Phosphate Coating