Hydraulic Metering Valve

[jthornton]

Is there such a beast as an easy to adjust metering valve for hydraulic cylinder that flows free in one direction and slows the cylinder down in the other direction? Before you ask why I want to slow my splitter down it's for my Huth HB-10 pipe bender...

Thanks
JT

 

[wndwlkr]

Here's some you could look at. http://www.surpluscenter.com/Hydraulics/Hydraulic-Valves/Flow-Control-Valves/

 

[jthornton]

Thanks, I think that is what I want.

JT

 

[cantoo]

jthorton, I have the Hydra star on my 36" splitter to slow down the wedge lift. There are different flow rate ones, this one has a knob on the top to control it. It has to be plumbed the right way to allow restricted flow. I've plumbed it both way and it doesn't seem to make a difference to me. Doesn't seem faster or slower either way. Make sure you talk to someone that already has the one you plan to buy. Gold coloured knob on top right of pic.

 

[jthornton]

I looked up the HydraStar and it looks like a a Chinese knock off of the Parker flow control valve. According to the description you should be able to shut off flow in one direction... I wonder if yours if missing a part. It is supposed to do what I'm looking for in a compact package. I need to check the maximum pressure of my system.

"Precision HydraStar flow control and full shutoff in one flow direction, unrestricted flow in opposite direction. Ideal for control of flow to hydraulic motors as a means of controlling motor speed. 3000 PSI, steel construction."

Thanks for the info.

JT

 

[jthornton]

This looks like what I need and cost effective too...

http://www.surpluscenter.com/Hydrau...NCE-WFC-800-IN-LINE-FLOW-CONTROL-9-7960-8.axd

JT

 

[Oldman47]

jthorton, I have the Hydra star on my 36" splitter to slow down the wedge lift. There are different flow rate ones, this one has a knob on the top to control it. It has to be plumbed the right way to allow restricted flow. I've plumbed it both way and it doesn't seem to make a difference to me. Doesn't seem faster or slower either way. Make sure you talk to someone that already has the one you plan to buy. Gold coloured knob on top right of pic.
View attachment 484379

If that adjusts using a needle valve you want the oil flow coming into it to be under the valve. It will work fine both ways but if you come in from below the needle itself will last longer. If you come in from the top it will cavitate at the tip of the needle.

 

[jthornton]

If that adjusts using a needle valve you want the oil flow coming into it to be under the valve. It will work fine both ways but if you come in from below the needle itself will last longer. If you come in from the top it will cavitate at the tip of the needle.

I'm not sure what you mean, there is only two connections on the last link I posted.

JT

 

[Oldman47]

The flow arrows on the valve will tell you which way to mount it but if there are no flow arrows you want the inlet to be on the end where any fluid must move up past the valve internals to get to the outlet.

 

[sweepleader]

The flow arrows on the valve will tell you which way to mount it but if there are no flow arrows you want the inlet to be on the end where any fluid must move up past the valve internals to get to the outlet.

The flow control is a check valve and a needle valve. The needle controls flow in one direction, the check allows wide open flow in the other. Not at all the same as a needle valve only. These are common on snow plow lifts that want to raise as fast as possible but not slam down when lowering. Speed and damage prevention are available from the same system at the same time. Thus you need to know which way flow is during lifting and which way it is during lowering to get the benefit the valve offers. It is not related to the "normal" use of a needle valve.

 

[olympyk_999]

The flow control is a check valve and a needle valve. The needle controls flow in one direction, the check allows wide open flow in the other. Not at all the same as a needle valve only. These are common on snow plow lifts that want to raise as fast as possible but not slam down when lowering. Speed and damage prevention are available from the same system at the same time. Thus you need to know which way flow is during lifting and which way it is during lowering to get the benefit the valve offers. It is not related to the "normal" use of a needle valve.

there are two types of these flow controls...1 way, which is what you described, and a 2 way which limits flow in both directions...parker makes both...

 

[sweepleader]

there are two types of these flow controls...1 way, which is what you described, and a 2 way which limits flow in both directions...parker makes both...

Yes! I forgot, 2 way has two checks and two needles thus two knobs. Nice catch.

 

[olympyk_999]

Yes! I forgot, 2 way has two checks and two needles thus two knobs. Nice catch.

no theyre nearly the same as a 1 way...but two ways don't have a check.
I guess you could make a two way out of 2 one way valves, and it would look like you described...

 

[sweepleader]

Hmm, well, an ordinary needle valve would limit flow in both directions, but it would be the same restriction in both directions and no checks. A two way flow control could provide different and adjustable flow restrictions in each direction.

Here's one that controls speed of a cylinder or motor in both directions independently.
http://dc-america.resource.bosch.co..._1/industrial_hydraulics_5/pdfs_4/ra27524.pdf

:{)

 

[olympyk_999]

That's not what I was talking about... That would require plumbing to both work ports/cylinder ports...im talking a basic needle valve on one work port to control flow in both directions...speed would be different between in vs. out because of the cylinder rod, but they're just meant for crude control. What you posted is for something that would require precision control...

 

[muddstopper]

I would ask are you wanting to control flow with cyl under pressure such as when making a bend, or just on return with low pressure. The cheap inline flow controls are usually not pressure regulated and not really accurate in controlling flow. As pressure increases, so can flow. A pressure regulated flow control will maintain constant flow under a wide range of pressures. One such as this http://www.surpluscenter.com/Hydrau...ONTROL-VALVE-W-RELIEF-RDRS150-16-9-064-50.axd might be a better choice than the http://www.surpluscenter.com/Hydrau...NCE-WFC-800-IN-LINE-FLOW-CONTROL-9-7960-8.axd one. Just depends on what you are trying to do and how precise it needs to be.

 

[jthornton]

I would ask are you wanting to control flow with cyl under pressure such as when making a bend, or just on return with low pressure. The cheap inline flow controls are usually not pressure regulated and not really accurate in controlling flow. As pressure increases, so can flow. A pressure regulated flow control will maintain constant flow under a wide range of pressures. One such as this http://www.surpluscenter.com/Hydrau...ONTROL-VALVE-W-RELIEF-RDRS150-16-9-064-50.axd might be a better choice than the http://www.surpluscenter.com/Hydrau...NCE-WFC-800-IN-LINE-FLOW-CONTROL-9-7960-8.axd one. Just depends on what you are trying to do and how precise it needs to be.

I'm just trying to slow down the bend sometimes so I can stop it easier at a given angle. I don't think precise flow control is needed just a slow and normal speed. I don't do production on this machine so I don't have a good feel for when to stop it. I looked at the first link before and it looks like over kill for my needs.

Thanks
JT

 

[muddstopper]

Every tube bender I ever saw was slow to start with, I expect yours is too. Most likely, the cheaper is flow control will be all you need.