Parker Parcolubrite -- history of zinc & manganese phosphate coatings

A. Hi Michael,
Technical questions on these types of issues are what the site is about, so thanks for the question. But comparing one brand, supplier, or proprietary to another, or praising or condemning it in this largely anonymous forum has proven unworkable ( huh? why?).

Alternate brands of break-in appropriate phosphate coatings are certainly available. But in any case I think there is more to the process than just the manganese phosphate step. For example, another proprietary [Endurion] was a special postreatment tin salt for manganese phosphate processes; and most brands also suggest a grain refiner before the phosphate.

Final answer: it's not impossible to develop a fully non-proprietary system for applying a robust full break-in phosphate, but it's a big job, not just a matter of making up a magnesium phosphate tank. Luck & Regards,


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

A. Hi
Parco Lubrite No.2 is a manganese phosphating process that chemically grows a finely crystalline manganese-iron phosphate coating on iron and steel. It is particularly recommended for wear resistance, in combination with oil or grease. Henkel is the current owner for this process, but there should be many outworkers about who can offer the service.

A. Parcolubrite is a trademark of Chemetall, so you should be able to get it from Chemetall-Oakite or one of their distributors.

A. Parcolubrite is a Henkel Surface Technologies product. They have sales and manufacturing plants in Canada.

Uh-oh it's listed as a phosphatizing process offered by Chemetall-Oakite in the Metal Finishing Guidebook. I guess it's time to call the trademark lawyers

A. Parcolubrite is trade name of Parker Chemical for a series of phosphating solutions. The most common one was Parco Lubrite #2 which was a widely used manganese phosphate process called out in many military and arms applications. Amchem and Parker merged way back that tied in Parcolubrite and Alodine trade names and I know Henkel owns rights to Alodine. As far as I know, while Oakite has fine zinc phosphate line, I don't believe that they have any manganese processes.

Chemplate was a job shop, I believe, mainly doing electroless nickel in the greater LA area. It was a company name rather than a process I believe.

PARCO LUBRITE is formulated to produce nonmetallic, oil-absorptive coatings on iron and steel bearing surfaces. These corrosion-resistant coatings consist chiefly of iron and manganese phosphates, and reduce wear on such articles as pistons, rings, liners, camshafts, tappets, motor blocks and similar bearing surfaces. Other beneficial effects may be summarized as follows:

A. Permits rapid break-in of moving parts without scuffing or welding by preventing metal to metal contact between the bearing surfaces.
B. Increases lubrication of treated surfaces due to the oil-absorptive coating.
C. Removes light metal scratches remaining from machining operations.
D. Retards corrosion.

  Good job there. I worked an old Storm Vulcan lathe back in the 70's. Central Engine Exchange was the name. The company was from Chicago, but Bob Glassman moved it to So. Miami. Loved the job. I would just grind down the camshafts to the specs. All hydraulic now so no level. The manual fuel pump lobe was the main problem. Dirty or no oil would wear that lobe out. Garbage then. I memorized all of the firing orders to all of them. I even had a couple of HP cams, and made master discs for them, but never got a blank cam to do one. Also taper was an issue. All lobes on each camshafts had a a taper. WHY: The taper would spin the lifter for lubrication & wear. I've built many HP engines after this. 202 heads on a 350 4BM, Blueprinted. Not this new days' crap, but had right at 500 HP. 69 Chevy truck w/front wheels off the ground.

A. Hi, Chris. I tend to believe Parker-lubrite was manganese based from the very beginning. I am looking at a 1939 book "Protective Coatings for Metals" by Burns and Schuh, which reports " ... in 1918 it was found by the Parker Company that the character of the coating was improved by the use of a solution of primary manganese phosphate. In this process, which came to be known as Parkerizing ...". I have some other references asserting the same. Sorry, I don't know offhand where the "Lubrite" term arose.

Without research I can't dispute the Wikipedia assertion as to whether or not there was a conversion to zinc phosphate during the war. My mentor Joseph Mazia was the director of the metals development lab at Frankfort Arsenal during the war, and later an employee of Parker+Amchem, and would have been able to give you the accurate and full history. Unfortunately he has passed away.

Regards,

A. Parkerizing is nothing more than a trade name for phosphate coating, just as Kleenex is a trade name for tissue.

Parker very aggressively advertised and promoted their products, to the point that "Parkerizing" was included in military and commercial specifications and on drawings.

As these parts were sourced through various sources over many years, some of them may have used Parker processes, and others used whatever phosphating process they had on hand. Some were proprietary, and some home-brewed.

I have myself processed parts which called for "Parkerizing" with both zinc phos and Manganese phos, none of it using Parker materials. Customers accepted this work just as though they had asked for a Kleenex and been given a Scott tissue.

As to color, zinc phos is usually light gray, but under some conditions it can be more nearly charcoal, and if chrome rinsed, may have a yellow or green tint.

Manganese phos is normally very dark gray, perhaps nearly black, but is sometimes charcoal. You may not be able to tell visually between a dark Zn phos and a light Mn phos.

In addition there can be a large variation in grain size in either process, and this, along with the visual difference between thin and thick coatings can make a significant difference in appearance.

Some specifications may call out "Parkerizing" and nothing else. Other specs may include requirements for coating weight, grain size and color.

Given the history involved, it is not surprising that "Parkerizing" done at different places and different times is different in appearance.

Is "Parkerizing" only that coating which is produced using Parker chemicals? Or, is Parkerizing any phosphate coating which serves the intended purposes of providing a low reflective surface which will absorb rust preventives.

It's the Kleenex versus bathroom tissue question, and you can argue either side ad infinitum.

And then there's the Thin Dense Chrome question, but I digress...

A. Try old Angiers book on bronzing of firearms Firearm Blueing and Browning [on eBay , Amazon, AbeBooks] -- According to that book phosphate finish is somewhat older -- there you can find some early variants of the process.

1906. Coslett's patent (zinc phosphate based)
1911. Richardson's patent (manganese phosphate based process).
Iron phosphate based processes are probably even older (late 19th century).
1929. German proprietary process (IG Farben)
According to W.Machu: Nichtmetallische anorganische ueberzuege (Nonmetallic inorganic coatings), Leipzig 1948.
Hope it helps and good luck!

A. I was a 35+ employee of Parker Rust Proof Company (name has changed with owners) presently retired. Was hired as a Chemist upon graduation of Missouri University. I was in upper sales management prior to retiring, and have used both systems in commercial installations. Parco Lubrite 2 (operates on the iron side Fe+2) gives heavy coating weights compared to Parco Lubrite 5 (operates on the NO2 side) no ferrous iron in solution.

Both coatings could be burnished for bearing surfaces. Coating weights can be reduced and/or refined by utilization of a conditioning agent prior to Phosphate e.g., Parcolene M. Some operational nuggets are given in this condensed response; should other information be required please ask me further. Individuals with knowledge concerning these pretreatments are becoming limited due to R&D efforts being focused in different more profitable areas and [loss of acquired knowledge] of personnel. The chemistry of this MnPO4 is very unique and I find it quite interesting regardless of profit margins.