Hydro relief valve construction observations

[jlord]

Today I swapped my relief valves to diagnose my "no reverse". The right one was leaking out the top, I figured it was bad. Sure enough, now I have reverse and no forward.

I know there is a fellow, much revered here and elsewhere, that refurbishes them. I'm not trying to take anything away from him as he does a very fine job of it, but while I had mine out I took a close look at how it was made.

It looks like the nose of the assembly has been pressed into a die that reduces the diameter of the opening to hold the cap in place.

I'm a long way from getting my lathe up and running, but I was thinking why couldn't a cylindrical die be made with an outside chamfer to open the reduced diameter allowing the internals of the valve to be removed and be refurbished? A die can also be made with an inside chamfer that would give the valve the same factory die pressed closure. That way there is no machining needed to open it up and no welding to hold the cap in place. No chips and no weld spatter/heat to deal with.

This could be done more than once to a valve if need be using a hydraulic press.

Maybe when I get my lathe back together I'll try making a set.

 

[digger]

Jim L.
That's all well and good except that Mark replaces all the internal parts with new.
If you have access to those, go for it man!

 

[jlord]

Charlie P.

No, no. You misunderstood my point. My point is, that instead off machining off the top of the die pressed top of the body of the valve and then welding the cap to the body of the valve after refurbishing the unit, a die can be made that can expand the "crimp" or rolled edge of the valve allowing removal of the cap. A similar die can be made that would crimp the nose of the valve closed again after the valve has been refurbished. Similar to the process of reloading brass ammunition.

This would allow the valve to be serviced more than just once. If the top cap is welded in place, then it would be very difficult to remove the cap again without destroying it. If replacement caps are available or easily made, then it's much less of an issue.

I'm just looking at how a process can be made better to achieve the same end result more easily and efficiently. To give added life to a valve so it could be serviced multiple times if need be, considering the cost of a new valve.

I'm only here to help. I'm not here to criticize anyone or anything, just to make things better!

When I get my lathe back together, I'm going to try to make a set of dies and try them out on a few valves. If the experiment is successful, I would like to send them gratis to the fellow who rebuilds valves for us.

 

[digger]

Maybe you and Mark should get together and do some serious brainstorming!
You might just be on to something big!

 

[mcafone]

I stopped welding them a few years back.
The problem I would have with opening them up without cutting the lip off is that the valve body is prone to cracking.
I have cracked them in the past by pressing them in place without machining them open

 

[jlord]

Mark C.

Do you think these valves are made of something other than low carbon steel like 1018? Or do you think maybe an alloy like tool steel so the check ball doesn't wear the seat too badly.

I figure if it cracks that easily then they must be made of a high carbon steel or a harder alloy and not that ductile.

I see in your post you say you don't weld them any more. Does that mean you close them another way such as staking or you just don't do them anymore?

I suppose that with the advent of "Viton" and better quality springs, once a valve is rebuilt it would last a very long time provided the bore the "O"-ring rides in is polished super smooth and the oil is kept clean.