Home /
Search 🔍
the Site

World's #1 on-line resource since 1989


Non-polluting alternative to Phosphating for pump parts?


Q. 1) We are phosphating a few pump parts called a) Cam ring (powder metal) b) End cover (SG 500 / 7 iron) both are always immersed in oil but come in to contact with sliding parts. Do we need to phosphate these at all (considering this being a polluting process)?

2) What is an effective alternative non polluting process?

G. Muralidharan
steering systems - Chennai, TamilNadu, India

affil. link
"Preparation of Metals for Painting"
by Samuel Spring

affil. link
"Phosphating of Metals"
by Werner Rausch
from Abe Books


A. Hi, Muralidharan. Yes, in my opinion you must phosphate these pump parts. I was involved in half a dozen manganese phosphatization installations for American manufacturers, which produced millions of reliable engine, auto, and earth moving equipment parts. Phosphating is an essential treatment to prevent scoring and galling during the break-in period even though the parts are immersed in oil; plus, oil runs off the parts and phosphatization doesn't. You don't want your customers to leave their new car at an airport for a month and then have things seize when they try to start it :-)

But why do you say that phosphating is a "polluting process"? All processes are "polluting processes" if you let the waste products out into the environment and "non-polluting processes" if you don't. The tiny amount of phosphatization products on scrapped parts surely can't be a problem; and phosphate is certainly not nearly as toxic or noxious as alternative chemical treatments like terne plating.

True pollution would be to once again fill the junk yards of the world with oily scrap by throwing away the fabulous progress we have made in the last few decades of doubling and tripling the lives of automobile parts. Good luck, and I hope you are not under unbearable pressure towards producing inferior parts and polluting our world with scrap by avoiding such an extraordinarily effective and proven surface treatment as phosphatization :-)

Ted Mooney, finishing.com Teds signature
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

help wanted ad
Plating Shop Manager [Salisbury, MD]
Junior Quality Engineer [Santa Clara, CA]
Plating Process Engineer [Wenatchee, WA]

Q, A, or Comment on THIS thread SEARCH for Threads about ... My Topic Not Found: Start NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

Chemicals &
Consult'g, Train'g
& Software

About/Contact    -    Privacy Policy    -    ©1995-2021 finishing.com, Pine Beach, New Jersey, USA