Is a Cross Over Relief Valve Important

[kennyd]

Great info - but I do have a request;

I would like to find a cross-over relief valve that has ｼ NPT ports (since that is what I am using for my build) and don't want to use reducers if at all possible.

is there any chance someone can direction me to Cross Over valve that use 1/4 NPT direct fittings?

Also, if I am going to get a unit (like the one depicted here from Surplus Center) I assume it is pre-set to 3000 PSI so how does one determine where it should be set for their specific requirement (and from what I read here 2500+ is where it needs to be). Should I just leave it at 3000 or if it has to come down and how does one know where exactly to set it?

1/2 NPT 30 GPM 1500-3000 PSI HYD CUSHION VALVE

Any clarity is greatly appreciated,

Jim

You won't find one with 1/4" fitting, at least me and my supplier couldn't whn I decide to sell CRV's. I could have had a custom block machined but that's not very cost effective considering the low volumes I sell. So we decided to use a block with SAE/ORB style, so one adapter can be purchased to go from that to whatever hose is being used-preferably JIC if having ones custom made. I try to stay away from NPT fittings whenever possible.

As for setting them, there is no simple way and it requires a specialized setup to do it, so at the advice of our supplier, we tighten the reliefs all the way, then back off 1/2 turn. That should set the pressure at near 3000lbs which is good to protect the cylinders, hoses, and framework. An exact setting is not critical for this application.

 

[J_J]

What is the big deal about using 3/8 in fittings adapters to match your1/4 in hose size to install the crossover relief valves, then why not just do it.

 

[RickB]

I think Curtis offers a CRV with 1/4" NPT ports. But a set of adapters isn't a big deal, especially if using a CRV with ORB ports and ESPECIALLY if one or both pairs of ports would benefit from 90 degree fittings.

 

[George2615]

If you look here, it is probably the same one, it says it is pre-set at 2000 psi.

Prince Crossover Relief Valve, Model# DRV-4HH | Relief Valves| Northern Tool + Equipment

This Prince is the same one I just bought for $68 plus shipping from a hydraulics shop in PA.

 

[BAP]

You won't find one with 1/4" fitting, at least me and my supplier couldn't whn I decide to sell CRV's. I could have had a custom block machined but that's not very cost effective considering the low volumes I sell. So we decided to use a block with SAE/ORB style, so one adapter can be purchased to go from that to whatever hose is being used-preferably JIC if having ones custom made. I try to stay away from NPT fittings whenever possible.

As for setting them, there is no simple way and it requires a specialized setup to do it, so at the advice of our supplier, we tighten the reliefs all the way, then back off 1/2 turn. That should set the pressure at near 3000lbs which is good to protect the cylinders, hoses, and framework. An exact setting is not critical for this application.

It seems to me a little strange that it is "so important" to have a cross over relief valve, then you just set them up by guess not any real measurement. If I am going to spend that kind of money, I want it set up correctly, not guessed at. I also don't understand what the problem with NPT fittings are, if installed correctly, properly tightened, they seal just as good and are a lot cheaper in most cases.

 

[LD1]

It seems to me a little strange that it is "so important" to have a cross over relief valve, then you just set them up by guess not any real measurement. If I am going to spend that kind of money, I want it set up correctly, not guessed at. I also don't understand what the problem with NPT fittings are, if installed correctly, properly tightened, they seal just as good and are a lot cheaper in most cases.

It doesnt have to be precise because it is there to protect against any sudden pressure spikes.

Most hydraulic fittings, hoses, cylinders, etc have at least a 2x safety factor. So you only need to get close for protection.

Kinda like relief valves on water heaters, or air compressors. It is designed to protect the tank from blowing up. So just as long as you are below that, and above normal working pressure, the exact setting is not critical.

The issue with NPT fittings isnt that they dont seal if done properly. Its HOW they seal is what I have issues with. Since they are tapered, it is easy to crack things (the taper puts lots of stress on things), they also require sealant (which can be pricey), cannot be reused as many times before threads are shot, and they just arent as good as the alternatives.

And FWIW, JIC are usually cheaper than NPT

 

[kennyd]

It seems to me a little strange that it is "so important" to have a cross over relief valve, then you just set them up by guess not any real measurement. If I am going to spend that kind of money, I want it set up correctly, not guessed at. I also don't understand what the problem with NPT fittings are, if installed correctly, properly tightened, they seal just as good and are a lot cheaper in most cases.

Like LD wrote, does it matter if it pops at 2800 or 2950? No, as long as it pops before something breaks. Try getting a 90* fitting clocked/looking just the correct way sometimes and you appreciate a ORB or JIC fitting.

Do you think the Prince ones form the Surplus Center are "precisely" set? Especially for that price? I am not trying convince anyone here...just stating the facts and offering an alternative.

 

[RickB]

It seems to me a little strange that it is "so important" to have a cross over relief valve, then you just set them up by guess not any real measurement. If I am going to spend that kind of money, I want it set up correctly, not guessed at. I also don't understand what the problem with NPT fittings are, if installed correctly, properly tightened, they seal just as good and are a lot cheaper in most cases.

So you prefer to set it up precisely to the exact PSI cracking pressure recommended by whom? Matters not much if the 'expert' one follows hasn't a clue as to what your plow width or hose rating is.

 

[J_J]

The only thing you are protecting is the cyl.

Do you know the rating on your snowplow cyl?

 

[chevy]

I got my cross over valve, reducing orifices & new hoses installed on my Meyer plow.
It was a very easy install with zero leaks. The only issue I have is that I got .032 orifices. I may need to drill then out larger.
The plow angling seems to be very slow.