Add a Double Pilot Check valve to Side Link Cylinder?

[kcoburn]

I bought an hydraulic side link cylinder for my last tractor. Soon after I installed it, I abandoned it because it rapidly allowed my back blade to drop. I bought it through the tractor dealer and they replaced it for me. No change with the replacement. This seems to be a common problem, described as "cylinder creep". Some suggest using a double piloted check valve cylinder as the solution. Hate to buy another cylinder. I now have a newer tractor and it looks like the cylinder dimensions are fine for this tractor. Is it possible, practical, and cost effective to add a double piloted check valve to the cylinder I have?

 

[nc redneck]

I have no idea off correct answer, but will be watching thread to see what kind of answers you get. I may want to do this in the future.

 

[J_J]

The valves are typically used in combination with spool type directional control valves to ensure leak free positioning of the actuator.

The inlet flow is free while the outlet flow is blocked. Pressure in the inlet line opens the check valve and allows free outlet flow.

The valves are typically used in combination with spool type directional control valves to ensure leak free positioning of the actuator.

The inlet flow is free while the outlet flow is blocked. Pressure in the inlet line opens the check valve and allows free outlet flow.

Fluid should be very clean.

Vickers - Double Pilot Check Valves, DPC1-10

This valve cost about $84. Is it worth it for your operation.

https://www.google.com/search?q=hyd...ONkAfEpYC4Cw&ved=0CAgQ_AUoAg&biw=1024&bih=479

http://www.surpluscenter.com/Hydrau...K-VALVE-1-2-NPT-25-GPM-3000-PSI-9-5606-50.axd

 

[oldnslo]

In reality all you need for the side link is a single pilot operated check. This would prevent the cylinder from creeping while holding a load but does not trap pressure from thermal expansion or while bouncing down the road with a load hanging on the 3 point hitch.

this one example:3/8 NPT 8 GPM BRAND PC37C PILOT-OP CHECK VALVE

Possibly contact Iowa Fluid Power in Cedar rapids. They are a Sun Valve distributor and probably have something on the shelf. They would possibly have the fittings required to plumb this up also.

I would recommend pilot ratio between 3 :1 & 5:1

 

[MtnViewRanch]

I bought an hydraulic side link cylinder for my last tractor. Soon after I installed it, I abandoned it because it rapidly allowed my back blade to drop. I bought it through the tractor dealer and they replaced it for me. No change with the replacement. This seems to be a common problem, described as "cylinder creep". Some suggest using a double piloted check valve cylinder as the solution. Hate to buy another cylinder. I now have a newer tractor and it looks like the cylinder dimensions are fine for this tractor. Is it possible, practical, and cost effective to add a double piloted check valve to the cylinder I have?

Just out of curiosity, how fast does it drop? How far does the ram extend in 10 minutes? Just wondering is all. To me anything at 1/4" per hour or less is acceptable. Some people think that it should not move at all. Those people need to have the check valves I guess. Problem with check valves is that you may loose other capabilities if your control valves are equipped with the float function. All depends on what is important to the operator I guess.

And to answer your question, yes you can add a DPOCV. You do realize that it is not the cylinder leaking, but your control valve. If it is the cylinder, the check valve won't take care of the problem, but 99.9% of the time it is the control valve.

 

[wdchyd]

........... You do realize that it is not the cylinder leaking, but your control valve. If it is the cylinder, the check valve won't take care of the problem, but 99.9% of the time it is the control valve.

Really?

If the side link cyl is extending when it is creeping?

Please educate me how you come up with valve problems at 99.9%

 

[MtnViewRanch]

Unplug the hoses and see if the cylinder moves. Of all of the cylinders that I have sold, 2 have been the problem. All others have been the valve.

 

[ovrszd]

You do realize that it is not the cylinder leaking, but your control valve. If it is the cylinder, the check valve won't take care of the problem, but 99.9% of the time it is the control valve.

Good answer Brian. Surprised someone else hadn't mentioned that yet.

 

[DK35vince]

And to answer your question, yes you can add a DPOCV. You do realize that it is not the cylinder leaking, but your control valve. If it is the cylinder, the check valve won't take care of the problem, but 99.9% of the time it is the control valve.

If true that means 99.9% of the time a cylinder w/check valve should stop leak down.
I know installing top/tilt cylinders with check valves stopped the annoying leak down problem I was having.
I have had the check valve cylinders on there for 10+ years now. They never move. They stay where I put them.

 

[J_J]

Really?

If the side link cyl is extending when it is creeping?

Please educate me how you come up with valve problems at 99.9%

I was thinking the same thing.

Manufacturers have a leak down rate for their valves and the dealer should replace the valve if it is under warranty, and leaking down more than the leak down rate.

I am sure the cyl manufacturer also have a leak down rate for their cyl.

I would say that the cyls are more at fault as people replace a lot more seals or cyl than valves.

Either one can be checked for proper operation.