Ways to limit flow for small cylinders?

[joea99]

Probably lots of threads on this but did not find any. I'm collecting parts to hook up a top and tilt kit. Got an 11gpm joystick valve coming which appears correct, from what I've read, as the tractor has an 8.5gpm pump and "they say" valves should be 25% greater capacity. So about right.

But, the cylinders are quite small, the tilt being not much larger than a soda can or one of those "monster" energy drink cans. So, I worry about the control being "twitchy" and/or "slamming" due to high flow rate.

I know there are needle valves for this which allow me to "fine tune", but wondering if there are cheaper alternatives, such as flow limiter, orifice fittings or like that. Besides being expensive(ish) it is not clear the needle valves will hold setting under use, vibration, etc.

 

[old and tired]

....Besides being expensive(ish) it is not clear the needle valves will hold setting under use, vibration, etc.

You'll need a "Check Valve" to hold a setting. I have a needle valve it work great on slowing things down to get the top and side link exactly where you want it.

 

[ptsg]

Yes, there are orifice fittings or also called restrictor fittings available that will do exactly what you want and it's most likely the cheapest solution.

However, I would try it out first to see how it will behave and then add the fittings since can be easily done after the fact.

Also, is this for the Kubota B21? They do list a total flow of 8.5 GPM, however this is the combination of the steering flow (1.3 GPM) and the rest of the flow actually works the loader, 3 pt and etc. In reality, you'll have 7.1 GPM at the joystick valve. Won't make much difference anyway.

Something like this:

https://www.farmandfleet.com/products/755271-apache-restrictor-hydraulic-adapter.html

 

[ruffdog]

I'm running a restrictor fitting like ptsg ^ shows on my grapple cylinder.

 

[joea99]

Thanks for the replies. Yes, it is for the B21 and happens to be the Kubota cylinders, glad it was still available.

Good idea to try it out first of course and be very careful first try. May not be till spring the way things are going.

 

[etpm]

Probably lots of threads on this but did not find any. I'm collecting parts to hook up a top and tilt kit. Got an 11gpm joystick valve coming which appears correct, from what I've read, as the tractor has an 8.5gpm pump and "they say" valves should be 25% greater capacity. So about right.

But, the cylinders are quite small, the tilt being not much larger than a soda can or one of those "monster" energy drink cans. So, I worry about the control being "twitchy" and/or "slamming" due to high flow rate.

I know there are needle valves for this which allow me to "fine tune", but wondering if there are cheaper alternatives, such as flow limiter, orifice fittings or like that. Besides being expensive(ish) it is not clear the needle valves will hold setting under use, vibration, etc.

If you decide on the orifice route then you could buy small and then open up the orifice with a drill bit. But you must take into consideration that the area of a round orifice will increase with the square of the diameter. So double the diameter will result in 4 times the area. I don't know what the orifices look like but recently i was presented with a bucket loader problem on one of my sons friend's small dozers. The blade would move fine in one direction but would move erratically in the other. One side was obviously suffering from some sort of restriction. After pulling hoses I determined that there was rubber in the crimp restricting fluid flow. I ran a drill bit by hand to cut out the bulging rubber and the blade now works perfectly. The restriction looked small but made a big difference. That area thing. In any case, if you can drill out the orifice, and have the drills, the math is easy to use to figure out how much more fluid will go through the orifice when enlarged. But really, if you have a good selection of number, letter, and fractional drill bits you can do this empirically. Try one orifice diameter. If good then leave it alone. If not then try the next size larger drill bit. And so on. Remembering that every increase in size will be magnified by the square of the difference.

 

[MtnViewRanch]

Thanks for the replies. Yes, it is for the B21 and happens to be the Kubota cylinders, glad it was still available.

Good idea to try it out first of course and be very careful first try. May not be till spring the way things are going.

Here is what I supply for the T&T sets that I sell.
2" dia cylinders get .030 orifice.
2 1/2" dia cylinders get .045 orifice.
3" dia cylinders get .060 orifice.

In theory you should only need one on the rod end port, but for whatever reason I have found the one at each port has eliminated any issues.

This seems to work well for 99.9% of my customers.

You should have 2" cylinders, so .030 orifice should work well for you.

 

[ROUSTABOUT]

Probably lots of threads on this but did not find any. I'm collecting parts to hook up a top and tilt kit. Got an 11gpm joystick valve coming which appears correct, from what I've read, as the tractor has an 8.5gpm pump and "they say" valves should be 25% greater capacity. So about right.

But, the cylinders are quite small, the tilt being not much larger than a soda can or one of those "monster" energy drink cans. So, I worry about the control being "twitchy" and/or "slamming" due to high flow rate.

I know there are needle valves for this which allow me to "fine tune", but wondering if there are cheaper alternatives, such as flow limiter, orifice fittings or like that. Besides being expensive(ish) it is not clear the needle valves will hold setting under use, vibration, etc.

Needle valve been holding 30 years here but I don't know how long the duration of your intentions are.

 

[joea99]

You'll need a "Check Valve" to hold a setting. I have a needle valve it work great on slowing things down to get the top and side link exactly where you want it.

The valve is said to have "internal checks" on each spool. Summit Hydraulics. Similar valves much cheaper from the universal Asian valve company, but with a hodgepodge of port types. And generally no PB adapter to be found.

 

[joea99]

Here is what I supply for the T&T sets that I sell.
2" dia cylinders get .030 orifice.
2 1/2" dia cylinders get .045 orifice.
3" dia cylinders get .060 orifice.

In theory you should only need one on the rod end port, but for whatever reason I have found the one at each port has eliminated any issues.

This seems to work well for 99.9% of my customers.

You should have 2" cylinders, so .030 orifice should work well for you.

Thanks, good starting points. Where do you get, or sell the adapters? Various fitting connection types?

For TnT I'd rather have "too slow" than "too fast". Speaking as Capt. Obvious.

 

[joea99]

Needle valve been holding 30 years here but I don't know how long the duration of your intentions are.

Never noted if they have lock nuts or the design will hold them. My intentions are one thing, age, etc are quite another.

 

[MtnViewRanch]

Thanks, good starting points. Where do you get, or sell the adapters? Various fitting connection types?

For TnT I'd rather have "too slow" than "too fast". Speaking as Capt. Obvious.

I build all of mine into the port adapters. They are all #6 ORB-M / #6 JIC-M. Either straights or 90s.

I believe that about any of the online suppliers have the type previously linked to in various sizes.

 

[LD1]

The internal checks in the valve are probably load check valves. You mention a joystick valve so I "assume" its a generic loader valve....and those are pretty common with load checks. Not the same thing as a check valve to prevent unwanted cylinder drift.

Personally Id try it without any restrictor first. You are controlling the cylinders with a manual valve not an electronic one. SO you can feather it just the same way you feather the loader or backhoe controls when you dont want it to move fast.

IF you do decide you want to slow it down....the inline needle valve/flow controls are what I would do. You can dial it in to your exact liking rather than being stuck with a fixed orifice size or having to change out orifices if you dont like the speed.

 

[joea99]

The internal checks in the valve are probably load check valves. You mention a joystick valve so I "assume" its a generic loader valve....and those are pretty common with load checks. Not the same thing as a check valve to prevent unwanted cylinder drift.

Personally Id try it without any restrictor first. You are controlling the cylinders with a manual valve not an electronic one. SO you can feather it just the same way you feather the loader or backhoe controls when you dont want it to move fast.

IF you do decide you want to slow it down....the inline needle valve/flow controls are what I would do. You can dial it in to your exact liking rather than being stuck with a fixed orifice size or having to change out orifices if you dont like the speed.

Trying it first is likely what I will do. I just don't completely trust my ability to "feather" a new and probably very stiff valve. Don't see any reason I'd ever want to move a box blade, scraper or rake "fast". +All relative, I guess.

It is listed as a "loader" valve, which I don't think is significant in this application. Am I wrong yet again? At first though I would think a "load check" and preventing cylinder drift are related. More coffee might help.

 

[BukitCase]

"It is listed as a "loader" valve, which I don't think is significant in this application"

It might be significant unless you actually intend to use the valve for a loader - it's quite common for loader valves, especially ones for smaller tractors, to include "regen" in the section intended for bucket curl - regen re-directs a portion of the pressure to the OPPOSITE side of the cylinders, purportedly to eliminate cavitation/jumpiness caused by getting air into the circuit - for any use OTHER than a curl circuit, this can cause "wonky" results.

I'm not sure whether it's always stated in descriptions whether a specific valve has regen in that valve spool, but I'd be asking before buying if it's NOT for a loader function... Steve

 

[LD1]

Yup, if its a regen valve it could cause you issues.

Got a model # and brand for the valve?

Also....the load checks (sometimes called anti-drop valves) are internal to the valve. And when trying to feather the loader and raise really slow....the weight in the loader (and therefore backpressure on that line) can cause the loader to actually go down instead of up when trying to move real slow. Thats what the load checks prevent

 

[joea99]

Yup, if its a regen valve it could cause you issues.

Got a model # and brand for the valve?

Also....the load checks (sometimes called anti-drop valves) are internal to the valve. And when trying to feather the loader and raise really slow....the weight in the loader (and therefore backpressure on that line) can cause the loader to actually go down instead of up when trying to move real slow. Thats what the load checks prevent

Thanks for explaining the "anti drop" thing. If I get any positional drift I can always consider putting checks on the cylinders. Some say they never experience that at all.

It's a Summit Hydraulics P40. Checked with them and they say this valve does not have "regen" and should work fine for my application.

Now that I have the valve, I kinda think I should have gone with a non joy stick. Lever sticks up higher than I imagined it would. Lack of real world experience is showing.

 

[LD1]

Thanks for explaining the "anti drop" thing. If I get any positional drift I can always consider putting checks on the cylinders. Some say they never experience that at all.

It's a Summit Hydraulics P40. Checked with them and they say this valve does not have "regen" and should work fine for my application.

Now that I have the valve, I kinda think I should have gone with a non joy stick. Lever sticks up higher than I imagined it would. Lack of real world experience is showing.

Good news on the non-regen,

I would just cut the handle down to a size that works best for you once you have the valve mounted.
cutting it down means you also have to move it less....cause loader valves usually have pretty long throws to begin with

 

[Fallon]

Here is what I supply for the T&T sets that I sell.
2" dia cylinders get .030 orifice.
2 1/2" dia cylinders get .045 orifice.
3" dia cylinders get .060 orifice.

In theory you should only need one on the rod end port, but for whatever reason I have found the one at each port has eliminated any issues.

This seems to work well for 99.9% of my customers.

You should have 2" cylinders, so .030 orifice should work well for you.

I'm happy with my FitRite plumbing & TnT cylinders on my previous & current machine. His restrictor setup works well.

 

[ruffdog]

Here is what I supply for the T&T sets that I sell.
2" dia cylinders get .030 orifice.
2 1/2" dia cylinders get .045 orifice.
3" dia cylinders get .060 orifice.

In theory you should only need one on the rod end port, but for whatever reason I have found the one at each port has eliminated any issues.

This seems to work well for 99.9% of my customers.

You should have 2" cylinders, so .030 orifice should work well for you.

Just thinking here....for every inch of piston movement, more fluid is displaced on the rodless side of the cylinder. So, if both sides of the cylinder have the same size restrictor, would it not be the one on the rodless end that is doing the work because it must flow the most volume of fluid?