Jump to content

Hydraulic press advice needed


Bob Geldart

Recommended Posts

I intend to build a press from parts sourced from Surpluscenter, I'll be using a 6 inch cylinder with a 12 inch stroke. Could somebody who has built their own press suggest which pump and adjustable valve I should buy.

 

cheers

 

Bob

Link to comment
Share on other sites

Hey Bob, Don has a manual by Dr. Batson on how to build a forging press. It's very helpful with matching components, and predicting performance. I'm currently gathering the odds and ends for a press, so I definitely can't say I've 'done it'.

Good luck, Craig

Link to comment
Share on other sites

Hey Bob, Don has a manual by Dr. Batson on how to build a forging press. It's very helpful with matching components, and predicting performance. I'm currently gathering the odds and ends for a press, so I definitely can't say I've 'done it'.

Good luck, Craig

 

Bob,

I second the recommendation for Jim Batson's book.

 

The 6X12 cylinder should be fine but watch your structure because you'll have quite a bit more power than the guys using the five inch cylinders. Frame and guide flex could be an issue if you use the C-frame style, you might want to consider the H-frame or guillotine types.

 

I use the log splitter pumps and valves from Northern Hydraulics, a "return to center" valve and a 16 gal. 2-speed pump with 5hp motor. Some prefer the single speed pumps and 5hp is a little low by some recommendations but I've had no problems with this combination on a couple of forging presses that have been in service for more than ten years.

 

Good luck and be careful, presses are more dangerous than they seem,

Hank Knickmeyer

henry knickmeyer

Link to comment
Share on other sites

Hey Hank, good to see you here.

 

I second Hank's recommendations for motor and pump and the H frame. It was his setup that got me started down the hydraulic's road and that combination has worked successfully for years.

There are three kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves. Will Rogers

Link to comment
Share on other sites

I agree too on Hank's. My 5hp and 2 stage pump does what I want when I want. I had a real electrical power issue in my shop. Basically had to wire in a 220v plug off the clothes dryer plug and make sure the wife doesn't turn it on while I'm forging. Amperage was limited too. The motor/pump combination works very well despite the limitations in my shop.

 

Dan

Dan Pfanenstiel

Link to comment
Share on other sites

Thanks for the replys.

 

I assume the 'log splitter' pumps from Surpluscenter are suitable and will probably be the type of pump I use. Why do some people prefer single speed pumps?

 

Most people seem to use valves with open centers, is there any advantage to a valve that maintains pressure in the centre? I can't think of any reason why I'd want to clamp anything with the press but some powerhammers have this feature so somebody must find it useful.

Link to comment
Share on other sites

Bob

I agree with these guys and would also add.

consider hooking your valve up to a foot lever so you can use both hands to hold your work.... I posted some photos of this on this forum a while ago. ( sorry I'm computer iliterate or I would give you the link to it but it is in this section under the title of hydrulic press ,sit down.) And also consider putting your pump in another room or outside if it won't bother the nieghbors....... the sound of hydulics is pretty loud. I run my press off my logsplitter

pump (13 GPM) I'm out in the woods where I'm not bothering anyone with the noise ....... because it is outside I can hear the oil bubbling thru the lines ( and my music too! ) while I'm using it ..... this was an unintended plus that I realized after hearing other presses being used that had the pump and motor built into the press.........

Have fun, presses ROCK

Dick

Link to comment
Share on other sites

Hi Richard, I was really tempted to bring back up your previous thread, but would you mind commenting on your remote motor/pump set up. How long are your lines (high pres. and return)? And, are there any pressure drop or other problems to watch for? Sorry for the newbie questions, I always assumed I'd use the shortest practical lines, but it would be nice to package the tank and motor in a cabinet a few feet away.

Sorry Bob for drifting your question off topic.

Take care, Craig

Link to comment
Share on other sites

craig

my lines are about 15 ft long...... they are 1 inch and the feed is rated for 3000psi.... it was exspenive . .... I can't remember how much but ,the return line wasn't so bad........ be careful about putting your pump and motor in too small of a space . they put out alot of heat that needs to get dissapated........ I haven't had any problems with the lenght

dick

Link to comment
Share on other sites

I built my own a couple of years ago and made a bunch of mistakes. If you can answer a few questions, I think I can help you avoid mine.

 

First: How much force do you want? 10 tons? 20 tons? more?

Second: how fast do you want the jaws to close? If it's too slow your work will cool before you can get much done and you'll put cold shuts in your welds.

Third: Given 1 and 2, how much do you want to spend on the frame and motor? A 6 inch cylindar is going to put you into a 5hp motor ($$$) depending on your shop power.

 

You have to engineer these things as a system. If you start "just throwing it together" you can make a mess and waste a lot of time and money (like I did).

If anything looks easy, it's because a professional is doing it.

Link to comment
Share on other sites

In answer to the above, I want the press to be capable of applying a pressure of about 30 ton. I want to be able to control this by using a variable pressure relief valve as I won't be needing this pressure for most of my work. I already have some heavy joists and steel plate which I will use to make the frame. I have a 1440 rpm 10HP motor to power the pump.

 

I've just tried to order the parts from Surpluscenter via their online ordering system. They wanted to add $4500 tax to an order valued at $800. I hope that was a mistake!

Edited by Bob Geldart
Link to comment
Share on other sites

To run few numbers:

 

a 6" Cylinder has an area of 28.26 square inches => 3.14*3*3

30 Tons is 60000 lbs.

 

Your max drive pressure is 60000/28.26 = 2143 psi.

 

 

The 6" Cylinder requires 28 cubic inches of fluid to move an inch, which is 0.121 gallons

 

 

Looking at surplus center's website, they have 11, 13, 16, 22 and 28 gpm 2 stage pumps. That rating is at the lower pressure - when your press will be openning and closing.

All those pumps are rated to 3000 psi so they will all do for your 30 ton beast.

 

The closing speeds will be (assuming your going run the whole 12 inch stroke):

 

11 GPM = 7.92 sec

13 GPM = 6.72 sec

16 GPM = 5.46 sec

22 GPM = 3.9 sec

28 GPM = 3.1 sec

 

I'd go with the 16 if I had the money.

 

But to get full speed, you'll need to have closer to the 3000 rpm that the pump is rated for. At 1440 RPM you'll only get about half that speed. Those pumps like direct drive, so putting pulleys and belts on them may wear out your bearings or make the seal leak.

 

 

I use log splitter valve because of the spring return. I like to be able to let go of the valve and have everything stop. Mine is rated 2500 psi with a built in relief valve.

 

I put a pressure gage right at the output of the valve so I can adjust it. I'm only running about 11 tons because my frame wasn't as strong as I thought it would be and it flexes.

 

I hope you are using at least 4" I beam and you may need 6" for it. I'm using 4" by 1/4" thick square channel and it flexes when I crank up the pressure (I can hit 20 tons with my pump).

 

 

To keep the heat down, you will need a lot of oil in the system, meaning a large reservoir. The advice I was given (and didn't take) was to have the capacity of the system (cylinder + hoses + pump) times 2. I don't run mine continously. I have a power switch next to the valve and turn it on and off when I need it. I've never had a heating problem because of that.

 

A power switch next to the valve is a must. An emergency shut off you can hit with the other hand is nice too. These things can hurt you even though they move slowly.

 

Surplus Center seems like a good operation, but I live in another state so I've never been through their sales tax calculator, however I think that $4500 may be a little high :rolleyes:

 

 

Good luck, contact me if you think I can be of any help.

If anything looks easy, it's because a professional is doing it.

Link to comment
Share on other sites

Thanks for the advice Steve (and everybody else). I'm using fairly heavy column 210mm x 133mm x 30Kg per metre (8" x 5" x 20lb/ft). Can you suggest a suitable valve from the current Surplus Center catalogue. Would item 9-6765 be suitable?

Link to comment
Share on other sites

That one should work well. It has all the good stuff, spring return to center, built in relief valve and 3/4 ports.

 

Looks like the same one I'm using.

If anything looks easy, it's because a professional is doing it.

Link to comment
Share on other sites

Hey Hank, good to see you here!!!

 

I built mine based on Batson's H-frame with the cylinder on top. Has been working great for a lot of years.

 

I use a 16 gal, 2 stag pump, a 5" cylinder, log splitter valve and a 5hp leason 1725 rpm motor. All from Northern.

Don Hanson lll My Webpage

Link to comment
Share on other sites

  • 2 weeks later...
  • 3 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...