Hydraulic accumulators...

[5030]

The issue with ANY hydraulic accumulator is the precharge. One, it has to be an inert gas and 2, the precharge pressure is far above what most owners are capable of producing, if, they had the availability of inert gas in the first place.

The other issue is, if the accumulator is pre charged to 'X' pressure, buying one and having it shipped to you presents some restrictions in the actual shipping.

In my situation, almost none of that applies as I have the high pressure inert gas available and the mechanical means to pre charge any accumulator to the required pressure, whatever that is.

 

[Smokeydog]

On the Kubota set only one accumulator might have been rechargeable. Mystery Allen bolt under a fitting. Pressures clearly stamped on Bosch accumulators. Guess made to be replaced instead of recharged like many automotive type accumulators.

Bought another NOS set to fit an McCormick tractor loader off eBay for -$40. Thinking they weren’t serviceable either but were precharged. They were for a smaller tractor. Haven’t got around to using them yet.

Many accumulators are pressure adjustable to fit the process requirements. Tractor loaders may not be that critical. Doesn’t take much displacement for a little give. Having two at different pressures gives a wide range of dampening.

Having experienced a loader with soft ride it is good option. Made the transport of 100’s tons tornado tree debris much easier on tractor and operator. Only time I valve it out is for some pallet forking and setting some construction beams.

 

[LittleBittyBigJohn]

I've charged several at work. We have a couple of charge kits and use high pressure nitrogen bottles to fill from. If a person is not aware it can be quite the shock at how much pressure is in a vessel with a normal Schrader valve that they are used to seeing on tires.

One of my Mom's neighbors had a motorcycle with shocks that had nitrogen accumulators. He decided to check the pressure with a normal tire gauge, it shot the little plastic scale all the way across his garage...

 

[5030]

Nice thing about owning a welding and fab shop is I have the high pressure Nitrogen on hand all the time (inert gas welding bottles) and I can have one of my employees or myself machine a custom adapter to fill them The one I bought comes empty but no issue pressurizing it in the shop. The 'rub' if you want to call it will be how many PSI of N will be required to effectuate the dampening I'm looking for.

My M's operate at about 2300 psi hydraulic pressure which I'll use as a baseline and adjust as required.

You really don't need a large volume accumulator from what I can ascertain because all it does is cushion the shock load.

I kind of equate it as similar to the in line bladder tank on my in floor PEX system, just a lot more static pressure.

 

[ptsg]

Nice thing about owning a welding and fab shop is I have the high pressure Nitrogen on hand all the time (inert gas welding bottles) and I can have one of my employees or myself machine a custom adapter to fill them The one I bought comes empty but no issue pressurizing it in the shop. The 'rub' if you want to call it will be how many PSI of N will be required to effectuate the dampening I'm looking for.

My M's operate at about 2300 psi hydraulic pressure which I'll use as a baseline and adjust as required.

You really don't need a large volume accumulator from what I can ascertain because all it does is cushion the shock load.

I kind of equate it as similar to the in line bladder tank on my in floor PEX system, just a lot more static pressure.

If you're planning on using the accumulator as a "soft ride" for the loader, you really only need about 400 to 600 PSI of Nitrogen.

 

[5030]

If you're planning on using the accumulator as a "soft ride" for the loader, you really only need about 400 to 600 PSI of Nitrogen.

Exactly what I'm going to use it for and I'll go with your recommendation as a starting point, thanks. A full 120 cubic foot bottle of N is between 2100 and 2300 psi.

 

[ptsg]

Exactly what I'm going to use it for and I'll go with your recommendation as a starting point, thanks. A full 120 cubic foot bottle of N is between 2100 and 2300 psi.

I think I said it before on another post but the one on my loader has 725 PSI and find I find it a bit too much because it only really works well with a full bucket. It's very nice to use it in that case but ideally, I would want it in the 400 or 450 PSI.

There is a lot of factors to it though, like loader geometry, cylinder size and so on. Since you have the equipment, it should be easy to adjust as you get the feel for it.

 

[Smokeydog]

Took a chance with large Kubota ag tractor loader surplus soft ride system to adapt to M59 TLB. Similar loader capacity. Did incorporate a needle valve to act as an adjustable orifice if needed any fine tuning. Ending up not needed but the added height put the ball valve within easy reach so it stayed an option.

While the max operating and relief pressure is approximately 2300psi, the dynamic closed circuit pressure can be twice that. Add curl and forward push on top of max lift. Having a pressure gauge to always read pressure is enlightening. Switched to 10,000psi electronic where I could have options of set-able zero, tare, net, recall max/min. Mixed results trying to weigh things.

The open station M59 has steel framed plastic windows mounted low, facing forward. Perfect for mounting the accumulators behind just in case. Significant potential energy stored in there.

 

[5030]

Why they are expensive to buy as they must be built to ASTM specs for high pressure vessels.

 

[Smokeydog]

With your skills and experience customizing a soft ride system should be doable. Not sure how Kubota stands on offering options for their current line up. Definitely an option I would pick now if buying new. RScotty and I lucked up in finding NOS Kubota kits surplus for pennies on the dollar. Worth it just for the accumulators. Came with various hard and soft lines, fancy gang valves and custom brackets. Seemed overly complicated compared to some add on generic systems. I’m sure Kubota engineers know a lot more than I. Only used one bracket and accumulators out of the kit.

I was lucky the design could have a manual valve easily accessible in the operator station and gauge easily visible. All being well guarded by loader frame components. An electric solenoid valve would work too.

To anyone who has carried hay bales, logs, debris or bushhogs with FEL bucket or grapple the difference is remarkably smoother and kinder to operator and tractor components.

 

[5030]

My ultimate goal is less hard bounce when transporting round bales from the field and loading them on to trailers as well as roading when bumps in the road cause the loader to jump even when not loaded. Not sure if I'll bracket it to loader or just let it hang on the hydraulic hoses. Roads around here aren't that smooth, typical Michigan secondary roads. It will be a spring time install no matter what so it's a couple months out which will give me ample time to collect all the components like hoses and fittings.

 

[jonsstihl]

piston or bladder types make a difference too. you are not supposed to bottom out a bladder type and piston types are sometimes rebuildable. usually you install them vertically with the fitting at the bottom so that any debris in the system does not wear out the seals constantly

I have two on the loader, one set to dampen unloaded (that one bottoms out when loaded) and one set to dampen when close to full capacity. then I have one on my 3 pt hitch all are piston type.
I used a gauge to get the hydraulic system pressures before buying the accumulators and talked to a hydraulic shop that does a lot of these and discussed the charge settings. it is a certain percentage of the hydraulic system that is the ideal charge setting. If you do the math I end up somewhere around 60% of the working pressure as a charge setting when loaded. except for the max load because I wouldn't really go far with a max load in the loader so I set the system with teh most common load which would be a bucket full of material.


my empty loader pressures are 500psi no bucket, 700PSI with empty bucket, grapple empty is 800, bucket full of damp dirt 1200 forks empty 600PSI and my max lift pressure is 2400PSI. I know My pump is a little weak but thats all she's got in her. For now the pump replacement is on the back burner. it still works well and hasn't gotten worse.

loader accumulator charged at 300psi and 800 psi. works great,
3pt set to 700psi works well with my 1200 lbs blower, has maybe just a little too much bounce maybe I would try 800 next time.

these are settings on a grand L4740 with a la854 loader and they seem to work well with my attachments. definitely a great mod makes the ride a lot smoother even though I don't road my tractor often I do have a lot of trails in the woods.

 

[5030]

Bladder accumulators are also rebuildable, You replace the bladder via the top fitting. I'd lean towards the bladder type simply for the simplicity.

 

[hayden]

Do you guys have on/off valves installed so you can turn the suspension on and off? The bigger Deere tractors all have this as an option including a control switch in the cab.

 

[ptsg]

Do you guys have on/off valves installed so you can turn the suspension on and off? The bigger Deere tractors all have this as an option including a control switch in the cab.

I have a ball valve on mine, rated for hydraulic pressure. Since I mounted mine, more or less under the control valve, I can easily access the ball valve to turn on/off as needed.

 

[Smokeydog]

Do you guys have on/off valves installed so you can turn the suspension on and off? The bigger Deere tractors all have this as an option including a control switch in the cab.

Ball valve below the gauge.

 

[jonsstihl]

Ball valve for both of mine. I would have loved to go with an electric solenoid valve and a switch in the cab but that added complexity in wiring especially since my loader is quick attach and I do remove it sometimes.
for your info , I have not shut them off since I installed them.


If you do go with a dual set up on the loader with one set up for unloaded conditions you really should go with the piston type. the bladders get cut on the valve when they bottom out and the low load charged accumulator will always bottom out with a load. I think some bladder types can be bottomed out but I doubt the cheap ones are designed like that. I would rather disassemble a piston type and change seals than try to stuff a bladder through the fitting hole. I have never done that but it doesn't sound like fun.

 

[screamin400]

I am running 900 psi in my 3 pt hitch with a 2k blower that sticks back quite a ways. I notice a little more bounce when the blower is encrusted in snow. I would guess an additional 3-400 pounds. With NY roads the way they are it rides great. Just slowly goes up and down. I also have a shut off inline but have never used it.