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Help with Rebuilding 80T 4-Post Hydraulic Press 1

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PWScottIV

Mechanical
Jul 21, 2002
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I just purchased this hydraulic press and power unit and I’m planning to fully refurbish it. The plan is to build a new stand that integrates the power unit, powder coat nearly everything, and make new stainless platen plates to cover the existing ones.
It’s my understanding that the press and power unit have never been used together before, but they seem well matched.

Press Specifications:
Manufacturer: Unknown
Cylinder External Dimensions: 11in OD x 17.5in
Estimated Tonnage: 10in ID x 2000psi = ~80T
Platen Size: 22in x 14in x 3in
Daylight: ~19in
Post Size: 2.375in x 40in
Post Clearance: 14.5in+ x 6.5in+
Bushing Size: 3in OD, x 2.375in ID x 3in


Hydraulic Power Unit Specifications:
Manufacturer: Unknown
Motor: 7.5HP Baldor/Vickers
Pump: Vickers Vane Pump
Regulator: ? 9869-OP
Gauge: 6000PSI

I’ve never worked on a press like this and I have a few questions before I get started:

Questions:
1. What type of seals am I likely to encounter and how would I go about replacing them if necessary?
2. Does anyone have any idea who the manufacturer of the press is?
3. If I flip the press upside down (so the hydraulic cylinder is above), would there be any drawbacks?
4. Is it a good idea to replace the bushings, and if so, what’s the best type and method of removal?
5. I plan on making some 1.25in thick 17-4 H900 stainless steel plates to bolt to the existing platens which I plan to machine a threaded hole pattern onto (3/8”-16 with 2in spacing). Does that seem like a good/bad idea?
6. What’s the best way to determine the maximum tonnage/hydraulic-pressure that is safe to use this press at?
7. Should I rebuild the hydraulic pump (e.g. seals) while I’m at it (proactively)?
8. What hydraulic oil should I buy?
9. I might make a smaller hydraulic oil tank to give the press a smaller footprint/height… What’s the best way to size a tank for this application?
10. What’s the best way to remove the rust from the posts without changing the diameter? (Nearly everything else is going to be sand blasted for powder-coating)
11. What sort of controls should I consider if there’s only occasionally going to be a couple people using this press?
12. Is there anything I’m not thinking of (e.g. potential disassembly/reassembly difficulties)?


Thanks a lot in advance for the help, I really appreciate it!
 
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Good grief that thing is rough. I hope you got it for only a nickle!

Drawback of inverting: If you turn it upside down you will have the problem of any leaks internal or otherwise causing the top platen to sink onto the bottom one. The last press I built controls for was a 450 Ton one upside down and they had sinking top platen issues. The top platen weighed 22,000lbs so it was a considerable and rather dangerous problem. They needed to block it or remove everything from inside it. They asked me to monitor it and raise it once it had sank an inch (which would take and hour or two).

I don't see much problem with tapped SS plates of that thickness other than reduced press stroke.

You cannot remove rust without reducing the diameter. I'd probably have them turned as little as possible to remove the rust then have them hard-chrome plated back up to the original diameter.

You can spend a lot of time doing things like rebuilding the power-pack. I'd not. I'd do your press stuff then run it. I'd not even change the ram seals. If there's a problem fix it, if not, use it.

For controls there's no way to say without knowing exactly what the press will be used for and possibly by who, as in production or research or prototyping.

A typical minimum usually includes a two handed control that absolutely prevents the operator from getting their hand crushed. These days a mechanical barrier around the sides/and/or/the back would be used in-conjunction with a light-curtain to recycle the press if a third hand reaches in.

Keith Cress
kcress -
 
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