Steel Composition of Hydrualic Pistons?

[archiphile]

Could any one answer the above question? I have seen a couple at the local scrappy. I would think that they would be some sort of hardened High Carbon Steel. I could be wrong thought


Best,

Archiphile

[matt87]

I've heard them to be a useful grade of tool steel. However, more crucially, most of them are chromed, and you certainly don't want to put that in a fire.

[archiphile]

Any way to remove the chroming? Could I sand it maybe or maybe I could have it turned on a lathe. Maybe I could chuck it up in my wood lathe and sand it with emery cloth and my fresh air welding hood?

[Shane Stegmeier]

My memory is pretty bad... But I think my client that used to work at a shop that made a lot of cyclinders said that most of the rods were 1045? But I don't trust my memory so why should you;-) most of them were chromed after they were made, they also did a bunch that were stainless I think I remember.

[ThomasPowers]

I don't think you would want to make your hydraulic cylinder pieces brittle high carbon steel; I'd think you would want tough medium carbon steel myself.

[Frosty]

Most are pretty mild steel for toughness, a few are as high as 1045+ but are special applications.

Sanding the chrome off isn't quite as bad for you as burning it off but it's still exposing yourself to serious carcinogenics.

If you have access to a metal lathe just hog it off with a 15-20,000ths cut. Typically it's just the rod that's chromed but there are exceptions.

The piston itself is typically mild as are the cylinders though the cylincers are typically DOM (Drawn Over Mandrel) mechanical tubing, NOT black pipe.

Frosty

[Ross_E]

You can de plate the chrome with a simple bath setup, but the chrome will not plate on whatever you use as the cathode so you'll need to use a big one. PM me if you want more info.

[ThomasPowers]

I'm betting that the solution you get after deplating is considered *serious* hazardous waste too. Look up Hexavalent Chromium; not something you want around your shop or house.

[wassomeoneelse]

I was given two pieces of hydraulic cylinder from a machine shop here in Baton Rouge, LA. Both pieces were chromed and were 1050. I looked at the paperwork the lady had when they were ordered. So, 1045 is pretty close. Of course, it does not mean all cylinders are 1045 or 1050. But hope this information can help you.
Bryan

[cami]

Just my $0.02:
We serviced a lot of cylinders where I started my apprenticeship. In spite of this I can't offer much advice. We kept chromed rod in stock. The machinist would use a torch to draw out any hardness where he would cut the stock to length with a bandsaw. My only involvement was to attach the ends to the cylinder rods and the procedure was simple: enough preheat to drive off any moisture and weld with 7018....and Lord help you got any spatter on the chrome...

[CBrann]

I have been wondering some of the same things. Particularly the alloy. And did some research before forging.

I have a long 7' x 2" hydraulic piston, that I am slowly turning into useful things. I have found that the chrome will flake off during forging or grinding. The chrome didn't burn or oxidize or anything, and I kept the forging only to bright orange. Forges well. Very hard to cut with abrasive wheel.

I didn't worry about chrome burning because it melts at 3465F or boil until 4840F. Both temps much higher than steel melting or forging temps. Also chromium is not known for rapid oxidation, think about stainless steel, doesn't rust. ALso nickel, often plated under chrome, melts at 2651F and boils at 5275F. Also not known for rapid oxidation ( also in stainless steel)