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I too am having problems with my press.

 

I had a couple of failures with the filter setup on my press a while back. I though the problem was head for the filter case, which was ambiguously marked as to flow direction. I replaced it with a much higher flow unit form Surplus Center, and that seemed to fix the problem.

 

Then, Wednesday, the filter spat the gasket (and a bunch of oil) out. I didn't panic this time, and shut everything down in good order. Since the filter would not go back on without cross threading, I put the backup filter on. That one ran about 2 minutes and spat the gasket out.

 

So now I've got 2 problems. The first is the existing filter head. I'm pretty sure the threads are buggered, so that will have to be replaced. The second, and larger issue is why is this happening.

 

The press is 15hp 3 ph, driving 12 gpm. The filter is on the return line (which should be zero pressure, right? The tank has a breather cap, so the tank is open to the air). I hard lined the return line, partly to deal with some shock issues and partly to give me some extra length on the return line. The system is tight, no leaks (except when the filter blows off :blink: ) the return lines are 1 inch all of the way back to the tank.

 

The filter I put on there was rated at 70 gpm, which is better than 5 times the expected flow from the pump.

 

Any ideas? There must be a good solution, there are plenty of presses out there and I've only talked to one other person who is having this kind of problem, and that turned out to be a restriction issue.

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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any resistance to flow will build pressure.. .. to see if you have a pressure problem, put a pressure gauge before the filter... and try it after the filter..

-have to have actual measurements of what the system is doing.. hard to tell by looking at it

 

-should be next to no pressure after filter... and maybe small amount before filter.. due to resistance of the filter packing to flow and the set pressure of the relief

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I would first examine the blown filters by cutting them apart and looking for any goo or whatever that may have clogged them, confirm that the filters are rated for hydraulic applications, and check the oil to see if it has dissolved any paints or sealants that may have been used in your system, then see where that takes you. Hydraulic oil has some unique properties....

Brian

As for the threads, normally they are standard pipe threads and should be available at the hardware store for under a dollar

Edited by brian458666
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I would sugest putting the filter on the suction line. In that postition if anything you will have a slight negative pressure. Even though there is theoretically no pressure on the return line, but depending on the size of your ram and the distance from the shuttling valve(to determine volume), you are still dumping upwards of 2500 PSI into an "open" system and hammering the hell outta that filter. Reguardless of its flow rate if it goes from no pressure to getting hammered its gonna resist some and that resistance will build pressure. kinda like holding an engine air filter in your hands and hitting it with compressed air. Your by no means exceeding its flow rate but if you dont have a good grip it still goes flying outta your hands. It is the difference in pressure from one side to the other that causes this. You could put check valves on both sides of the filter and that would keep fluid in it and might help i suppose.... I would just put the filter on the suction side and stop worrying though.

 

My 2 cents anyway.

 

Good luck

 

Edit: If you had to hard line your return to minimize shock then it is clear your putting a big slug of pressure into that line. Outta curiosity if your running 1 inch return lines, what size are your feed lines?

Edited by Bret
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Hi Geoff,

 

Would you comment a bit more about the shock issues you were having that led you to hard line your return. Sorry if you had mentioned it before and I missed it. Were you also able to put in that hydraulic hammer that was mentioned in an earlier thread in front of the filter.

 

Since you have a good cushion on the gpm side, could it be that you're developing more pressure than you're thinking. That's a good bit of motor, could it be turning more rpm's than the pump is rated for. I believe it's been sort of figured out that pressure is needed to push through the filter, but it would probably interesting to see what kinds of pressure your filters are getting exposed to. Maybe there's a partial obstruction downstream of the filter, but before it dumps into you tank.

 

Hope it sorts out, and the answer should be helpful to others, Craig

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Geoff,

 

This sounds like something very weird is going on ... I'm wondering if the speed of the output of your 15 hp motor is matched to the speed what the pump you have is rated at..

 

You mean it is a 12 GPM pump? Could you possibly be running the pump faster than it is rated for?

 

this is a very weird problem and I have not heard anybody having so much bad luck with a filter...

 

My sympathies and I hope you get it cured .

 

Dick

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The motor is a Balder, rated at 1800 rpm, the pump is rated at 11.8 gpm at 1750 rpm, I figured that was pretty close, but I will check again just to be sure.

 

When I first built the press I had the filter hung on the return line, as the piston went to the ends of travel, the line pulsed. Eventually the filter unscrewed (at least that what I thought....hmmm.) So I changed the mount to make it more rigid. When I moved the pump and motor under the stairs, I hardlined the return to give me a bit of extra length (so the press wouldn't be smack up against the wall) and mounted the filter on the wall of the stairs, in the hard line.

 

I'm headed for a blacksmith's swapmeet today, I'll pick some brains there today.

 

Thanks guys,

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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This is going to sound like a really stupid question, but are you sure there's no blockages in the line causing a pressure jump? Most of these filters have a very low pressure rating and I imagine even a quick pressure jump might cause them to blow. You may want to put in a guage on the line to see what's happening.

Edited by Al Massey
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A line blockage is what the brains I was able to pick yesterday were able to come up with. So now I need to dump the tank :angry: , and check the lines down stream form the filter. My thought is that a blockage between the filter and the control block would have manifested other than in the filter, so a blockage must be between the filter and the tank.

 

In any case, it's gonna be messy.

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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Press.JPG

 

I just want to check my thought process before I start ordering parts.

 

1) At idle the flow goes from the pump to the control block though the filter and back to the tank. There should be just about 0 pressure in the system.

 

2) When the ram is moving flow goes from the tank, through the pump, into one port of the cylinder, out the other port, to the control block, to filter and to the tank.

 

If there is a blockage between the control and the filter, then the flow would be blocked, the filter would starve but not explode.

 

If there is an intermittent blockage above the (acting like a flap valve) then you might see a transient pressure spike, blowing the filter.

 

If there is a blockage below the filter, it might also be intermittent, that could close up the return line, causing a pressure spike, blowing the filter.

 

Is there some other place I should look? Am I missing the boat completely?

 

Is there any reason to increase the size of the return line? It's currently 1 inch. I did get one suggestion to do that.

 

I will put a gauge on the system, but mostly that will tell me there is a problem about 1/2 a second before something blows, not really all that useful.

 

As before, any help will be appreciated.

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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I'd say almost certainly the blockage would need to be between the filter and tank return to blow it. I can't really see pressure spikes between the pump and control causing that problem, because just operating the control in short strokes, like gradually tapering down a bar, you get quick pressure "spikes" all the time in the line running to the control and with the setup there- basically identical to mine- you don't (or you shouldn't!) blow off the filter on the return.

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[

 

Geoff,

One item not discussed much is air or "gas" in the cylinder circuit...this may create pulses (during porting to the tank) which may cause problems as you are experiencing. During the pressure stroke this gas gets compressed and creates a delay in the work done as would a flexible press frame.

Twelve gallons per minute is a lot of flow , this is going in and out of your tank at the same time ( not always) and the turbulence may be creating air getting picked up by the pump.

 

I have all the pieces for a press sitting in the shop...two priorities are a stiff frame and the ability to bleed the system. I want to avoid putting "work" and time into the frame or the "compressable fluid" It does not look as though I will be getting to that until next year.

 

Jan

Edited by Jan Ysselstein
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One other suggestion for safety and cleanliness sake. Not sure who recommended it to me (on this forum) when I was building my press; install a relief/dump valve right after the pump that feeds back into the tank will/should prevent any blow outs from malfunction or overloading.

 

Sorry I don't have any other new diagnostic thoughts to add. The only problem I've had with my press was a low pressure issue; turned out to be a faulty pump. By the way Surplus Center mailed a replacement immediately, once I called them. Problem solved.

CUSTOM KNIVES BY JL RHODES

JLRKNIVES

 

-------------------------------------------------------------------------

God bless you. I thank God every day for the freedom to spend time with those I love, and time to pursue this craft.

 

"Adversity is a test for strong men."

"What one man can do, so can another."

"NO excuses, just do better next time."

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Geoff,

 

is the return line 1" on both sides of the filter? and are the fittings all 1" on the return side? Almost sounds like you could have a small fitting between the filter and the return tank...

 

If the filter was got clogged in the short time you used it there should be a lot of gunk in it... Was there?

 

Non of this makes since...

 

Putting a gauge in on the return line is not needed but for trouble shooting purposes it would serve you well...put it on the tank so you can see what is happening

 

all the way to the tank

 

If you do put a gauge in make sure you don't restrict the line with a small fitting... use the same size as the hose....

 

your diagram and thinking are correct....

 

What is the speed of the pump rated at? Not the GPM but the RPM's ?

 

this is so frustrating ... I can imagine you are about to your wits end.... I would be...mad.gif

 

Dick

 

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I'll go tear into the filter today, but I didn't see anything obvious.

 

This is the pump I'm using

 

1.66 cu in displ

13.7 GPM at 2000 RPM

3000 PSI max

3000 RPM max

Inlet SAE 16 rear

Outlet SAE 12 rear

SAE B 2 bolt mount

CW rotation

7/8" x 1-5/8" long keyed shaft

7" x 5-3/4" x 5-3/4"

Shpg.13 lbs

 

The motor is rated at 1800 rpm, so I deliberately over-speced the pump.

 

 

The return is 1 inch all of the way through.

 

Yah, I'm really scatching my head. I really appreciate all of the help.

 

When this beast is working, it works great, plenty of power, and as the operator gets more skill, great control. I just wish it was more reliable. I realy don't want to have a intermitant flamethrower in my shop.

 

Geoff

Edited by Geoff Keyes

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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Geoff,

 

Well I'm at a loss on this as well as you.... I guess a gauge on the return loop would show you a spike...

but the filer is already doing thatmad.gif

 

I'm not sure what you could learn from knowing how much pressure is in the return loop. but it could tell you how fast the pressure builds

 

and if it changes with each stroke.. I suppose it would make you feel like you were trying but I'm not really sure what the info would lead

 

you to next... When you do figure it out please let us in on it too...

 

I don't know much about running three phase motors... Is there a chance the motor could be running faster than it should?

 

the three phase motor is the only " odd" part of your system as compared to what most people use... A three phase should work fine if it is

 

run on three phase power ... Industry runs them all the time without problems... So I'm stabbing at the dark and wondering about how

 

you run yours? BTW if it is running the speed you think it should then your idea of roughly 12 gmp is correct in your thinking

 

Dick

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I'm running a 30 hp phase converter. It's hard to know what the output of the wild leg is doing to the speed, but it measures pretty close to where it's supposed to be. Without some way to read the actual speed of the output shaft, I'm going to assume for now that its running close to the rated speed. I'll hold that idea for later. If this set of re-builds doesn't fix the problem, I'll look into that.

 

Thanks everyone,

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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Don't worry, voltage won't affect the RPM, that's a function of line frequency (60 Hz) in induction motors. No, there is no chance of the motor running faster than it should.

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[i][size="3"]is achieved not when there is nothing left to add, but when there is nothing left to take away.[/size][/i][/color][/font]

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Geoff

 

still with the filter problems, i would still move it to the suction line between the pump and the tank, but i don't think it will solve the problem. also the return line does have pressure and it can be quite a bit. it only becomes zero (atmospheric)after it exits the port and is falling.

what is the filter you are using flow and pressure rating, is it rated for the oil or fluid you are using?

 

Joe

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Geoff,

 

this is like playing twenty questions.wink.gif How about this one... Does the tank have a built in filter that you may not have seen ... If it was clogged that would build up the pressure in the return line.. Some tanks do have built in filters.. If it is a used tank it might be clogged up from a previous life...

 

Good info on the three phase running .. I learned something , thanks

 

Dick

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Right now I'm holding, waiting for my replacement parts to arrive. Here is my plan.

 

1) Dump the tank and pull the suction side strainer, just for drill.

 

2) Replace the 1" hardline with 1 1/2" black iron (same stuff, just bigger).

 

If that doesn't fix the problem, I'll start again. If there is a blockage down stream from the filter I should find it, but in any case, up-sizing the line my be the cure (I've had a couple of people come to me and say that they had seen this problem and that a bigger return line was the fix.)

 

I just want to get this machine to point where it's safe. Other than this issue, it's a great tool.

 

I'm so stressed by this right now I spent all of last night dreaming about how to fix it, which would be great except that my dreams were clearly nonsense when I thought about them in the AM. Just my brain in runway mode, all RPM, no load :lol: .

 

I will keep you all in the loop.

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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Geoff, If you told us where the filter is mounted I missed it. If the filter is mounted ON the tank so it dumps directly (preferably through a baffle) to the tank, you won't need to concern yourself with restricted flow between the filter and tank. And a shield around the filter would be nice, too. Not only to protect the filter but to help contain unwelcome surprises. And another couple of ideas- what if you split the return to flow through 2 filters in parallel...or it would be simple to add a pressure switch that would stop the system at overpressure....and so on.

Brian

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  • 2 weeks later...

Geoff,

 

Any headway on your press problems?

 

~Bruce~

“All work is empty save when there is love, for work is love made visible.” Kahlil Gibran

"It is easier to fight for one's principles than to live up to them." - Alfred Adler

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I got caught up in another project. We've been living with the worlds worst kitchen ever since we moved in almost 6 years ago. We have a big remodel (as in tearing down everything above the foundation and starting over) in the planning stages, but we just couldn't stand it any more.

 

In true remodel style, what should have been "move a couple of cabinets here and move the fridge there" became "rip up the sub floor and start over". OTOH, we've only spent about $300, everything is either a craigslist find or from one of the building salvage places, even the granite counters were "free" (we had to haul and re-cut). If anyone is interested, I can post some pictures of what we've done.

 

As for the press.... My plan is to dump the tank and turn the unit sideways, then plumb the filter on a short straight run (about a foot) of 1 1/2" pipe into the tank. My thought is that this will give very little place for a pressure spike to build, even if it happens again. While the tank is empty I will check for goop, birds nests and the like. I'm going to keep the hard line idea, but I'm going to up size the whole thing to 1 1/2". This is the plan, which I've put together with the kind help of a bunch of folks on the forum and elsewhere. I hope to tackle all of that Monday, the kitchen being just about done.

 

I keep you all posted,

 

Geoff

"The worst day smithing is better than the best day working for someone else."

 

I said that.

 

If a thing is worth doing, it is worth doing badly.

- - -G. K. Chesterton

 

So, just for the record: the fact that it does work still should not be taken as definitive proof that you are not crazy.

 

Grant Sarver

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Since you're tearing it up anyway, maybe add in a water (hydraulic) hammer just before the filter. Congrats on the kitchen project. Almost done has to be a good feeling, those can be never ending.

 

Craig

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