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OT Hydraulic forging press/ power hammer

kpotter

Diamond
Joined
Apr 30, 2001
Location
tucson arizona usa
I have been building small hydraulic forging presses. I run a 5hp motor and a 16gallon per min two stage pump. The forging press moves pretty fast, what I want to do is make a self contained hydraulic hammer sort of like an air hammer. I am thinking about using a 30 gallon per minute pump with the 5hp motor but keep the pressure around 200 psi. I should see ram speeds of around 15inches per second on a 3 inch cylinder. I will set up the valving to allow the cylinder to cycle like a power hammer. The low pressure should keep the HP needs very modest and wear and tear on the system tollerable. I just made a 4 inch cylinder with a 14 inch stroke, I put 1.5 inch ports on it they are huge so that oil flows very freely. Anyone ever seen anything like this I have seen giant hammers but never small ones, I am thinking 50-100 lbs ram and 200 blows per minute probably less but a guy can dream.
 
Way back in the day, around 1910 or so, they did build some hydraulic power hammers- they used water, rather than oil. Grant Sarver once sent me an old scan of a book featuring one. They were big, and heavy, and they did work- but the mechanical and steam versions work much better, so they never really caught on.
I cant find the scan right now, I am not in the US, and its on my other computer back home.
But as I recall, it requires much more power, and larger sized everything, than you are discussing.

Still, cant hurt to try.
 
I have never had the privilege to own a power hammer but I have seen a few in operation. They are generally really springy. Literally. Some that I have seen were built on the principle of a hammer on the end of a leaf spring. The operator engages a foot clutch and the hammer is given a shove and then springs back. I have also seen homemade air systems like you mentioned but never saw one run except on u-tube. Not a great explanation but that's the way I see it. The only problem I see using hydraulics is going to be how to control the force the hammer hits with. I guess if you are just trying to forge down something in a hurry tehn it may not matter how well you can control the force. But then you have a forging press which seems like it would do just that. How do you propose to control the force on the hammer?
 
I own an air hammer, and have run different air and mechanical hammers over the years.
It is true that feathering the force is something that is very desirable for freehand, open die forging.
And this is quite easy with mechanical hammers, using a slip clutch, and with air hammers, using a treadle actuated air valve.
I would assume you could use a treadle to actuate a hydraulic valve, but I have no idea how fast, or controllable, this would be.
I think the problem would be that you need really large lines, and high horsepower and pressure, to get the ram speed you are talking about- big enough that it becomes much cheaper and easier to use air or mechanical hammers.
I use a hydraulic press for some single hit forging, and the faster the better- I dont think 5hp is anywhere near enough for multiple hits. You need to fly this one past Larry Langdon- he is going to have a lot of input and ideas, I am sure.
 
No clue about a forgeing hammer

But a hydraulic hammer on a track hoe has nitogen accumulators allover it and some serious valving.Cheep ones cost about 30k.
 
Don't be dis-couraged by naysayers.

These guys run very hi-speed in a hydrualic press.

The die set is a blurr, sorry I can't find a stroke per minute speed,
but it sounds like a machine gun in operation.

Transfer Notchmaster
 
That's an interesting project....... a small hammer. Possibly hydraulic but maybe electric, air or a combination with mechanical components.
 
ive spent 20+years specialising in forging machinery, and a good chunk of that on hammers. The hydraulic hammers that work well, consistently and reliably all use the same principle. Oil to lift, which increases the pressure in a nitrogen accumulator, that then provides the motive force when the oil is dumped from the underside of the cylinder.

Ill build a 'blacksmiths' sized hydraulic one, one day, when I can do it just because. This day will be when ive retired from working on hammers! My honest opinion is you are on a bit of a hiding from the get-go. Air is nice and forgiving and you can do a lot with it ! If you get an air leak around your piston seal it doesn't turn into a flame thrower when your hot working :D
 
Don't be dis-couraged by naysayers.

These guys run very hi-speed in a hydrualic press.

The die set is a blurr, sorry I can't find a stroke per minute speed,
but it sounds like a machine gun in operation.

Transfer Notchmaster

You sure thats hydraulic?
From my reading of it, they are using DC motors that are running mechanical linkages.
I do know that the same company, Schuler, owns the old Beche, which is one of the very first manufacturers of self contained air forging hammers, and they still make both mechanical and air powered forging hammers, listed on the very same page you linked to.
Seems to me that if they had the tech to do forging with hydraulics, they would sell such machines, instead of selling both mechanical and air hammers and presses instead.

The new technology for this sort of thing is the servo controlled DC motor machines like Aida is now using in punch presses- Servo Press, AIDA DSF-C1 Gap Frame Servo Presses for Metal Stamping
direct drive servo motors with enormous torque, and which are controllable as to speed even at different points of each pressing cycle, meaning maximum control.
Of course, they are high tech and expensive, not home shop buildable.

The idea of a hydraulic forging hammer comes up every few years, I have been reading dreamers who propose it since at least the late 90's, and I have never seen one of em actually build a working model.
But Kevin could do it if anyone could.
 
You sure thats hydraulic?
From my reading of it, they are using DC motors that are running mechanical linkages..

Yes, I walked right by it. Sat there and watched it work. And yes it's hydraulic.

I'm sure of it, because it replaced (2) older mechanical units,(it's that much faster) and this really
raised my eyebrows, so I made sure to get it straight that it is, in fact, hydraulic.
 
It works on a demo hammer because the cycle times and "stroke" are very short. Nothing like the OP proposes. It will be interesting to see what he comes up with. Ciao.
 
I have a Sahinler power hammer -- air hammers are SO much more controllable than mechanical trip hammers.

Kevin's idea is pretty neat! The challenge will be cycling a (typical) 50 - 150lb powerhammer ram at 200 blows per minute.

Kevin: Ric Furrer (well known, very talented blacksmith/bladesmith) lurks here one in awhile, and now that Grant has passed, he's probably the most knowledgeable guy about power hammer history, function and lineage. You might drop him an email...
 
If this is what the O.P. needs...50-150 lbs, here is the 90lb pavement breaker manual:
http://www.stanleyhydraulic.com/LinkClick.aspx?fileticket=fC4lD-YWUss=&tabid=163

and it needs 8 gpm.

Right, but that jackhammer has a 3/8" ram. The ram on a power hammer is much bigger. I just ran the calculation for an 8" ram, 9" travel (typical throat between dies), with a .3 second cycle time, and I'm getting ~ 800 GPM (!) Now, figure the drive piston can be smaller than the hammer ram, but you're still moving a 100 lb ram...

Power hammers are seismic events when they run...
 
Right, but that jackhammer has a 3/8" ram. The ram on a power hammer is much bigger. I just ran the calculation for an 8" ram, 9" travel (typical throat between dies), with a .3 second cycle time, and I'm getting ~ 800 GPM (!) Now, figure the drive piston can be smaller than the hammer ram, but you're still moving a 100 lb ram...

Power hammers are seismic events when they run...

The trick is to couple the high pressure low volume shock wave from 'fluid hammer' into a high volume high frequency motion. The mechanism for doing this is the hydralic ram. The high pressure wave can be controlled by the rate of closure of the clapper valve on the air dome, and the low pressure large motion blow frequency can be controlled by the volume of air in the dome.
 
Well I have one of those breakers mine's branded JCB, and it runs off a 7.5 hp honda petrol engine. It has a nitrogen accumulator on the end of the handle. Never considered it for blacksmithing. Mind you I have a mechanical power hammer still waiting rigging up since I got it several years back :(

Andrew
 








 
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