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Awhile back I had mentioned in a thread that I was going to look into putting filters on the return lines of the wheel motors (JD 4830) so if a WM piled up, it would not contaminate the whole hydraulic system. At the time I had said that, when I find out the particulars I would start a thread and share what I learned. Well, I forgot all about it until I received a message from another member asking. Well, I talked to the shop foreman at my JD dealer, asking about oil flow requirements for the motors so i didn't cause a restriction and possibly more heat. When I told him why I was asking, he informed me that there are 3 filters in the hydraulic oil tank filtering all the oil as it leaves the tank so filters on the WM return lines would be redundant. Thanks for the reminder gavdalbs
 

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Are you sure? I thought most hydro sp sprayers were plumb in a x, and closed loup. Double pump pack one pump for 2 motors and the motors are in seires. If that's the case the oil gose from pump to one WM to next WM and back to pump with a small amount of oil bleed off for cooling and lub, the bleed of oil is replanaced buy charge pressure from tank/charge pump.

Madsnake
 

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Are you sure? I thought most hydro sp sprayers were plumb in a x, and closed loup. Double pump pack one pump for 2 motors and the motors are in seires. If that's the case the oil gose from pump to one WM to next WM and back to pump with a small amount of oil bleed off for cooling and lub, the bleed of oil is replanaced buy charge pressure from tank/charge pump.

Madsnake
That is how nitro does it too, and the bleed off is 20% apparently
 

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I'm afraid that there are two issues, both bad. A typical hydrostat is different than a hydraulic motor dumping its fluid back into the reservoir with 100% of the fresh supply being filtered from the reservoir then pressurized by the pump and sent out to do work again as in a typical orbit motor's job.

Although a hydrostat gets its filtered oil from the reservoir in this manner by the charge circuit, it really just keeps the hydrostatic components full. There are generally no seals in the pressure zones of the hydrostat, just tight tolerence metal to metal fitment. Any leak past is replaced by the charge pump to keep things full of fluid. Most of the volume in the hydrostat goes directly from the motor returns directly back into the hydro pump's inlet in a constant unfiltered loop.

If you could get a high enough volume filter, theoretically you could filter each return line from each wheel motor, until you put it in reverse. When the flow is reversed, which is exactly what happens, your filters would turn into 10,000 PSI hydraulic bombs.
 

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If you could get a high enough volume filter, theoretically you could filter each return line from each wheel motor, until you put it in reverse. When the flow is reversed, which is exactly what happens, your filters would turn into 10,000 PSI hydraulic bombs.
And if the filters didn't blow up, all the particles they had filtered would now be going back through the system in reverse!

Andrew
 

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If you wanted to do something, you could make a reservoir with a magnetic trap. The magnetic trap portion would have to be out of the flow path. There are magnetic drain plugs that seal the opening when removed for inspection.
 

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When I built coil tubing rigs we installed filters in both lines and filtered oil back to the pumps. The units were designed to run at up to 6500psi but could peak at 10,000. We used Donaldson high pressure filters that were rated at 10,000psi and 150gpm with reverse flow check valves. It is possible to buy filters that work in both directions but they are twice the money. These were closed loop systems with Linde pumps and Poclain 2spd LSHT motors run parallel. I also used suction and charge pump filtration. The valves that bleed oil back to the tank are called hot oil shuttles and are designed to return a fixed amount of oil back to the tank regardless of oil flow or direction, it always takes off the low pressure side. We had motor failures but the contaminates never made it back to the pumps.
 

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When I built coil tubing rigs we installed filters in both lines and filtered oil back to the pumps. The units were designed to run at up to 6500psi but could peak at 10,000. We used Donaldson high pressure filters that were rated at 10,000psi and 150gpm with reverse flow check valves. It is possible to buy filters that work in both directions but they are twice the money. These were closed loop systems with Linde pumps and Poclain 2spd LSHT motors run parallel. I also used suction and charge pump filtration. The valves that bleed oil back to the tank are called hot oil shuttles and are designed to return a fixed amount of oil back to the tank regardless of oil flow or direction, it always takes off the low pressure side. We had motor failures but the contaminates never made it back to the pumps.

That's what I love about the Internet, just when you think something should be invented you can find out that it already exists, you just have to get out your money.
 

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When I built coil tubing rigs we installed filters in both lines and filtered oil back to the pumps. The units were designed to run at up to 6500psi but could peak at 10,000. We used Donaldson high pressure filters that were rated at 10,000psi and 150gpm with reverse flow check valves. It is possible to buy filters that work in both directions but they are twice the money. These were closed loop systems with Linde pumps and Poclain 2spd LSHT motors run parallel. I also used suction and charge pump filtration. The valves that bleed oil back to the tank are called hot oil shuttles and are designed to return a fixed amount of oil back to the tank regardless of oil flow or direction, it always takes off the low pressure side. We had motor failures but the contaminates never made it back to the pumps.


so you are the Prick who put those heavy high pressure filters under the carriers on the trailblazer rigs!!!!!!!! ;):cool:
 

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Awhile back I had mentioned in a thread that I was going to look into putting filters on the return lines of the wheel motors (JD 4830) so if a WM piled up, it would not contaminate the whole hydraulic system. At the time I had said that, when I find out the particulars I would start a thread and share what I learned. Well, I forgot all about it until I received a message from another member asking. Well, I talked to the shop foreman at my JD dealer, asking about oil flow requirements for the motors so i didn't cause a restriction and possibly more heat. When I told him why I was asking, he informed me that there are 3 filters in the hydraulic oil tank filtering all the oil as it leaves the tank so filters on the WM return lines would be redundant. Thanks for the reminder gavdalbs
Thanks for the reply licensed to kill. Seems the question is still relevant just need someone to be the guinea pig and let us all know the results.
 

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If you wanted to do something, you could make a reservoir with a magnetic trap. The magnetic trap portion would have to be out of the flow path. There are magnetic drain plugs that seal the opening when removed for inspection.
Magnetic traps won't help much either. Most of the rotating and moving surfaces in the motors aren't magnetic. Many are brass and would not be caught by a magnet.
 

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Dont forget that most filters only filter out the (nuts & bolts).
If tou are serious about filtering it properly you would be best putting an aftermarket
filter on!
 

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so you are the Prick who put those heavy high pressure filters under the carriers on the trailblazer rigs!!!!!!!! ;):cool:
Actually I'm not unless they bought rigs used from others we built for. The first few rigs we built had the filters inside the frame then I moved them outside. Three high pressure Donaldson filters for the injector and auxiliary hydraulics and two medium pressure filters for the charge pumps. The reel didn't have a high pressure filter because the Linde motor was operating at low pressures and are very reliable. My goal was to make the system simple, reliable and easy as possible to service. My rigs were unique because I used allot of pipe for hydraulic plumbing and all hoses were very carefully made and placed in organized, neat arrangements. There is nothing I hate more then building a nice machine and turning the hydraulics and electrical into a spaghetti bowl. My rigs took longer to build but in the end I believe they were more reliable and easier to service ;).
 

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That's what I love about the Internet, just when you think something should be invented you can find out that it already exists, you just have to get out your money.
All you have to do is ask ;)
 

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When I built coil tubing rigs we installed filters in both lines and filtered oil back to the pumps. The units were designed to run at up to 6500psi but could peak at 10,000. We used Donaldson high pressure filters that were rated at 10,000psi and 150gpm with reverse flow check valves. It is possible to buy filters that work in both directions but they are twice the money. These were closed loop systems with Linde pumps and Poclain 2spd LSHT motors run parallel. I also used suction and charge pump filtration. The valves that bleed oil back to the tank are called hot oil shuttles and are designed to return a fixed amount of oil back to the tank regardless of oil flow or direction, it always takes off the low pressure side. We had motor failures but the contaminates never made it back to the pumps.
It would seem to me that you would only need a filter on each motors out line when traveling in a forwards direction. Then one way bypass valves on the output side of that filter so when reversing there is no counterflow through that filter so contaminants couldn't go back into the system. Some sort of pressure differential monitoring would seem desirable also to pick up when filter flow is restricted due to component failure.
 

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Ozzie, this is a closed loop hydrostatic system that runs in both directions equally so in one direction one filters cleans oil from the motors to the pump and the other filter bypasses then (the check valve prevents reverse flow through the element) in the other direction the other filter takes over. Both filters have bypass valves that open at around 150psi (I believe) that bypass the element if the filter is plugged. The motors are tied in series (either two or four) so the failing motor can't contaminate the good motors and are filtered together. The system protects the pumps from the motors being the motors are more prone to failures. The system isn't perfect and if I was still there I would probably be using filters that clean in both directions by now. One of my problems with building equipment is there is always room for improvement... It is just my way.
 

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Actually I'm not unless they bought rigs used from others we built for. The first few rigs we built had the filters inside the frame then I moved them outside. Three high pressure Donaldson filters for the injector and auxiliary hydraulics and two medium pressure filters for the charge pumps. The reel didn't have a high pressure filter because the Linde motor was operating at low pressures and are very reliable. My goal was to make the system simple, reliable and easy as possible to service. My rigs were unique because I used allot of pipe for hydraulic plumbing and all hoses were very carefully made and placed in organized, neat arrangements. There is nothing I hate more then building a nice machine and turning the hydraulics and electrical into a spaghetti bowl. My rigs took longer to build but in the end I believe they were more reliable and easier to service ;).


So we're you at the Rig Shop in Nisku?


Really sounds like the ones I worked on were your early ones.

gotta say they were simple compared to the tds rigs... what a rats nest.
 

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Nope, built fifty one rigs in Brooks over eight years. They were well service units with on board air compressors, everything was truck mounted. They used them mainly for blowing sand out of wells after they were fractured.
 

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filters

You can use 1 filter for both directions using a Graetz rectifier setup. I don't remember whether this is an off the shelf item but if not it should be a piece of cake for a custom manifold shop.

Steelman
 
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