lupiphile Posted November 4, 2012 Share Posted November 4, 2012 So I've finally gotten around to getting this c-frame press wired up and moving but, it, or rather I with it, has a bevy of issues. It's a single end press( no real guides) with an overwhelming array of electronics. That alone is enough to make me uncomfortable. It has two modes : Run- wherein you hit a button and the press cycles down till this electronic line pressure switch tells it to reverse direction and then it continues until it hits a micro switch. The pressure switch can be set from 0- 3000. The other mode is Jog- wherein you can use the up or down button to move the ram where ever in the stroke.....or blow the start capacitor, break the guide rod, trip the main breaker, and trap whatever you were working on helplessly under 35 tons till you fix the problem. I've been looking through all these wonderful pages of information and it seems most people don't have these sorts of problems. My press has a 7.5 hp motor, powering a 1.5" ram with about 14" of stroke. It moves very, very, scarily fast. I know just about nothing, on the subject of presses. Clearly my motor is generating far too much pressure, but what it the best way to alleviate that? That pressure switch only works on the least usefull mode and the wiring for this machine seems more complicated than god, and most of the systems I've seen represented here and elsewhere don't have to have electric pressure switches to keep them from destroying themselves........ they just stroke till they can't and the operator reverses the direction. That's what I want. There's abunch of hydraulic guru's that call this forum home, but really just about anyone knows more about hydraulics than me so any help at all will be appreciated. Thanks in advance, Take Care , Matt Quote Link to comment Share on other sites More sharing options...
Daniel.85 Posted November 4, 2012 Share Posted November 4, 2012 So the pressure release on the control valve is only useable on one of the modes? Do you know the GPM that the pump is rated at? Also what is the cylinder diameter? You mention the 1.5" ram but all the pressure tables I have go by cylinder diameter. Not sure about the ratings of your press but if its at 35tons it would take a 6"cylinder at 2500psi to be at 35tons, or a 5.5" at around 3000. Most hoses are rated at 3000psi, I dont see many forging presses that go over that. Quote Link to comment Share on other sites More sharing options...
Daniel.85 Posted November 4, 2012 Share Posted November 4, 2012 Most pumps are 2 stage, the scary fast movement you talk about could be the first stage for when there is no resistance, once the ram hits the material being worked it automatically switches to the lower gear, otherwise you would have to wait forever to go the length of the stroke. You would have to work something in the press to see if it has that, or look and see if there is any information on the pump itself. The pump is usually located next to the motor, its run directly by the motors shaft usually. Quote Link to comment Share on other sites More sharing options...
lupiphile Posted November 4, 2012 Author Share Posted November 4, 2012 Definitely not two stage, it let me know on that one, from the super fast pressure build up. The electric pressure switch works as a read out when its cycling in that mode, and there is also a dial guage on the out feed of the pump, It jumps VERY fast. As to the size of the cylinder; I've only measured the ram because that's what is visually accessible, but I've looked at the whole shebang and I'd say the width of the cylnder is about 4-5"? It's definitely not supposed to be run over 3000 psi as there are warnings all over the machine. Thats sort of my issue. It seems like the thing is set up to destroy itself in anything other than that silly run mode. It wasn't built as a forging press.Thanks for your help, Matt Quote Link to comment Share on other sites More sharing options...
Daniel.85 Posted November 4, 2012 Share Posted November 4, 2012 It sounds like the pump is working very well, pushing those pressures. The issue being that the machine cannot control the pressure could be in the wiring to the control valve or a physical part of the control valve itself. If you can follow the hose from the motor, it should lead to the control valve, it will have 3 other hoses coming out of it, 1 to the top of the hydraulic cylinder, 1 to the bottom and 1 going back the the fluid reservoir. The 1 going back to the fluid reservoir is the return line for normal and pressure release situations. The control valve may have some manual adjustments... maybe not. All this is just based off the way the ones I know of work, like if you were to buy the parts now and build one... I might be way off with your machine. Quote Link to comment Share on other sites More sharing options...
jimmy seale Posted November 4, 2012 Share Posted November 4, 2012 that was what i am thinking...check for or install a flow limiter. but i would defenatly talk to someone that knows what they are doing, hate to mess up a pump,motor,or any of the hydros. and the safety issues would be enormous! so be safe and hope ya get her sorted out, jimmy Quote Link to comment Share on other sites More sharing options...
nonjic Posted November 4, 2012 Share Posted November 4, 2012 Any photos? sounds like a cool press (or will be when its set up right!) Be very carefull if you are temped to cycle the press against cold metal to verify pressures etc when setting it up. I heard about a guy last week, that was killed a couple of years ago doing that when the billet he was pressing against flicked out. Quote Link to comment Share on other sites More sharing options...
lupiphile Posted November 6, 2012 Author Share Posted November 6, 2012 Hey Y'all, I've finally managed to figure out how to resize and attach files. So mayhaps this shall clarify some of the more inchoate aspects of my pretty poor verbal descriptions. First off I removed the top cover and took some measurements and Daniel the induction guy, you are spot on. the cylinder is 6" (od). The control valve is featured in pictures three and four. three is an over all, and four is the nema plate(or the hydraulic equivalent). The first picture shows the pump head on with the dial indicator, to show line pressure. Thats the primary indication I have, that it's not a two stage pump. If I put a piece of wood under the ram and lower it ( like a two by four, not white oak) as the ram moves through it, there is no slowing and the pressure spikes alarmingly. The second picture shows the side of the pump with three knobs and an imprint that says "press torque" all of them seem to be screwed in tight, and as I really don't know how they work I didn't want to mess with them. The third picture shows the control valve, or really the control solenoid. There are two dial like things on either side that someone had written up and down on respectively. The dial like things don't move easily, and I'm lacking in enough bravado, or have been supplied with enough hardship of my own making, to not go lunging at them with a set of channel locks. The fourth picture, as previously mentioned, shows the nema plate. It says 3000 psi max, but I'm not sure thats an indication of it being set to limit pressure, It seems to me like more of a warning. The fifth picture, is kind of a general shot. You can see the control panel, with the run and jog and the up and down buttons. The digital pressure line switch is the little box off to the left. After having mucked about with the machine for the last few days, I will say the start capacitor is overloaded. It was installed with the belief that the machine would be wired for 408, It was rewired by the machinery dealer for 230. The little amperage dial on the capacitor only goes up to ten and the main lock out fusebox is fused with 15amp fuses. The motor says it draws 21.3 amp @ 220 60hz. So my question( amongst many) is can I safely ommit the start capacitor? or get one for a higher amperage? and fuse the whole thing at 20 or 25, or am I in danger of messing up something more important(i.e. expensive) like my motor? If this were a drill press or even a hammer, I wouldn't thinK twice, But I'm not real familiar with what type of strains are put on a motor in a hydraulic setup. How do you all have yours, done? Starter or no? Alright thats about enough of this for the day, I thank you all for any and all advise forthcoming , Take care, Matt Quote Link to comment Share on other sites More sharing options...
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