All temp splitter fluid

[nixon]

Excuse my ignorance on this ,and if it's been beaten to death ,My apologies .
But what do the AW ratings signify ? as in AW32 , Aw 46 , etc...
My reason for the question is that I split wood all year round , and I'd like to use a fluid that is up to the temp swings without going to the bother of changing it seasonally .
And , while I'm bugging You folks.... Would Kubota SUDT 2 be a good choice for an all temp fluid ?
Please be kind , as I have very sensitive feelers

 

[NHGUY]

AW32= 10wt
AW46= 20wt
AW68= 30wt
AW100=40wt

This is the ISO rating vs the SAE rating.

 

[nixon]

Thanks for the info .

 

[tom slick]

For future reference:
In AW32, for example, the "32" is the ISO rating which directly corresponds to the viscosity.
Handy chart:
http://www.bobistheoilguy.com/viscosity-charts/

NHGuy's numbers are a little bit off.
ISO 100 is a SAE 30 engine oil or SAE 80w to SAE 85w gear oil
ISO 68 is a "thick" SAE 20 engine oil or SAE 80w gear oil
ISO 46 is a SAE 20 engine oil or a "thick" SAE 70w gear oil
ISO 32 is borderline between SAE 10w and SAE 20 engine oil or 75w gear oil.

Blame the confusion on the SAE system. Their numbers represent ranges. ISO numbers correspond to specific viscosities.

 

[George Bynum]

AW is AntiWear

The number, in the ISO preferred number sequence used, is the viscosity in centistokes. The sequence goes 10, 15, 22, 32, 46, 68 (100 ...)

AW fluids have various Viscosity Index (VI) values. Higher VI fluids have less change with temperature, as with multi-viscosity engine oils. In my OPINION, there is no excellent hydraulic oil suitable for wide temperature variation. For long life in mobile (and some industrial) equipment, low loads are used to warm oil to a reasonable level before full loads are applied.

 

[MolaKule]

I would recommend Schaeffer's #264 in ISO 68 for Penn. weather.

 

[George Bynum]

Originally Posted By: MolaKule
I would recommend Schaeffer's #264 in ISO 68 for Penn. weather.
MolaKule's recommendation is excellent as a fluid, but I disagree with the grade; this is likely a gear pump on an internal combustion engine operating at a governed speed of about 3600 rpm. That thick a fluid, in ambient temperatures below about 90F, will probably create inlet cavitation at those speeds. PERSONALLY, I'd use a 32 cSt grade (good to fluid temperatures of about 130F) or a 46 cSt grade good to around 145F.

Properly designed log splitters spend most of their operating time at full flow, low pressure, and rarely get "hot". Be SURE to have a good filter on the unit, not the cheap cellulose (the software will delete the appropriate word here, so let's say garbage) items usually installed by the manufacturer. Proper spin-on elements are available from many reputable manufacturers. Look for the word "beta" in the pore size ... letter B for Beta, current standard, something like B10(c)= something over 50. B5(c) is better. Higher values for the = are better. In moderately critical systems, we would recommend something like B5(c)=200. Oil sampling is the real answer to filtration determination, not the elements itself, however.

 

[roadrunner1]

Originally Posted By: George Bynum
Originally Posted By: MolaKule
I would recommend Schaeffer's #264 in ISO 68 for Penn. weather.
MolaKule's recommendation is excellent as a fluid, but I disagree with the grade; this is likely a gear pump on an internal combustion engine operating at a governed speed of about 3600 rpm. That thick a fluid, in ambient temperatures below about 90F, will probably create inlet cavitation at those speeds. PERSONALLY, I'd use a 32 cSt grade (good to fluid temperatures of about 130F) or a 46 cSt grade good to around 145F.

Properly designed log splitters spend most of their operating time at full flow, low pressure, and rarely get "hot". Be SURE to have a good filter on the unit, not the cheap cellulose (the software will delete the appropriate word here, so let's say garbage) items usually installed by the manufacturer. Proper spin-on elements are available from many reputable manufacturers. Look for the word "beta" in the pore size ... letter B for Beta, current standard, something like B10(c)= something over 50. B5(c) is better. Higher values for the = are better. In moderately critical systems, we would recommend something like B5(c)=200. Oil sampling is the real answer to filtration determination, not the elements itself, however.


I agree with George's recommendation, an ISO 32 would be my first choice. I have several different hydraulic systems using John Deere HyGard Low Vis (ISO 32)and it preforms flawlessly.

 

[MolaKule]

Most heavy duty hydraulic log splitters use this single-stage pump

http://www.northerntool.com/shop/tools/product_200329722_200329722

or the lighter ones (from your local hardware stores, etc) use these two-stage pumps

http://www.northerntool.com/shop/tools/product_200321055_200321055

When I designed and built logsplitters, I always used the single-stage pumps with rebuilt Caterpillar dozer cylinders.

In a properly designed system with the correct pipe or hose sizing and proper reservoir capacity, you will never get cavitation until you use an ISO150 or higher fluid in cold weather.

An AW ISO 68 fluid is about a 30 weight equivalent. You have to look at the spec sheets to see what the fluids real viscosity is at 100C.

Using an IR scanner, I saw temps up to 150C even in cold Kansas winters.

 

[nixon]

Thanks to each of you for taking the time to answer my post . I'll locate a source of schaeffers # 264 before spring. ( that's when I'll be doing a fluid change any way ) I'm most likely going to go with the aw46 .
One thing I didn't understand is the filter info . What would be a good source of the filters that George Bynum made reference to ?
My log splitter info..
American CLS 25 HH , 8 hp Honda,16 gym pump ,4x 24 cylinder.
One of my other concerns is the oil tank size, only a bit over 5 gallons. Seems very small for a 16 gym pump.

 

[George Bynum]

Originally Posted By: nixon
One thing I didn't understand is the filter info . What would be a good source of the filters that George Bynum made reference to ?
My log splitter info..
American CLS 25 HH , 8 hp Honda,16 gym pump ,4x 24 cylinder.
One of my other concerns is the oil tank size, only a bit over 5 gallons. Seems very small for a 16 gym pump.
Interesting that there is no filter on these units; I expected to recommend a change of element, not installation of a filter! I am not a sponsor here, and while I do not sell or recommend any particular filter to my clients, my choice would be one of the ones with a "standard" truck size spin on for east of procurement. Two significant manufacturers are Parker and Hydac. There are dozens of others. From Parker, I'd look at the 50AT20BN25DDN. From Hydac, I'd look at the MFBN160G20. These don't have a gauge for dirty filter indication.

They also have large ports, 1-1/4NPT. Do NOT put in the pump suction, rather return to tank.

There are smaller units with 3/4NPT ports; they will bypass cold, but be ok once the oil warms up. Wherever you bought your splitter likely sells filter assemblies.

As for reservoir size ... in INDUSTRIAL systems, we frequently take the pump flow in GPM and use a reservoir 2x that in gallons ... so from that criteria, would suggest a 30 gallon reservoir. Mobile applications fudge on that sizing, and get by with it pretty well for reasons beyond this forum. The manufacturer has experience that his sizes work with baffling in the reservoir he designs. It wouldn't be my choice, but I don't have his experience with HIS SYSTEM.

Oh, these are PROBABLY (well almost certainly given the motor hp, flow, and pressure) what the splitter industry calls 2-stage pumps, 16 gpm to perhaps 600 psi, then drops to 4 gpm up to the 2500 psi limit. Industrially we call the concept "high-low" and usually realize it via separate valving and 2 pumps.

 

[nixon]

Originally Posted By: George Bynum
]Interesting that there is no filter on these units; I expected to recommend a change of element, not installation of a filter!


Sorry if I didn't make myself clear . It does have a filter. It's a spin on type made by FPC.
It' a 30 series 10 micron cellulose filter. ( el cheapo ) so, what I was looking for is a better filter element . Sorry for the poor communication skills . And, again thanks for helping me out .

 

[George Bynum]

Originally Posted By: nixon
Sorry if I didn't make myself clear. It does have a filter. It's a spin on type made by FPC.
It' a 30 series 10 micron cellulose filter. ( el cheapo ) so, what I was looking for is a better filter element. Sorry for the poor communication skills. And, again thanks for helping me out.
It's not your poor skills, it is mine; I went to the splitter manufacturer's website and they didn't mention a filter! Given that info, FPC offers an element with "real" media, FPE 30-10G 3µ/5.5µ/12µ Microglass. For this type application, it is more than satisfactory. The only issue I have is the 18gpm max flow, but as used, that probalby won't hurt. Industrially, we try to use an element at under 50% of max.

None of the sites I use for crossovers list it, so they are either a small outfit or use proprietary sizing AND are small.

 

[fraso]

I also have been trying to figure out the correct hydraulic fluid for my log splitter, which I just bought last summer. It is an American MSR AM24HC, which appears to be similar to the American CLS AM-25H. It was built in 2005 and my owner's manual recommends that any brand of good grade, lightweight hydraulic oil can be used.

I called up the factory and they told me that the factory fill is an AW46 oil. There is no need to change the hydraulic oil unless it appears burned although they recommend an annual filter change.

I also called some oil company tech lines and an AW32 was generally recommended in this application and AW22 for extreme-cold splitting. PetroCanada was the most helpful and told me that in these applications, a useful rule of thumb is to aim for a viscosity of around 13 cSt at the oil's operating temperature. For PC's Hydrex fluids, the temperatures at which the viscosity is around 13 cSt are:

• AW22 - 55°C (131°F)
• AW32 - 64°C (147°F)
• AW46 - 74°C (165°F)
• AW68 - 85°C (185°F)

A simple way to tell is by putting your hand on the cylinder because 60°C (140°F) is about as hot as anyone can stand. If it's too hot to touch, you probably need an AW46. Otherwise, an AW32 will do. They also recommended a maximum oil temperature of 70°C (158°F) for longer oil life.

As for filters, the one on mine is a spin-on Prince FA10.

 

[George Bynum]

Originally Posted By: fraso
I called up the factory and they told me that the factory fill is an AW46 oil. There is no need to change the hydraulic oil unless it appears burned although they recommend an annual filter change.
I'd add "or unless there is water in the fluid".
Originally Posted By: fraso
I also called some oil company tech lines and an AW32 was generally recommended in this application and AW22 for extreme-cold splitting. PetroCanada was the most helpful and told me that in these applications, a useful rule of thumb is to aim for a viscosity of around 13 cSt at the oil's operating temperature.
It is SO NICE to see a company who understands what is important. I wonder, however, if their statement wasn't to aim for a viscosity of NOT LOWER THAN 13 cSt at the oil's operating temperature" Parker, Eaton, and BoschRexroth generally recommend in the 15-40 cSt range at operating temperature with maximums at startup ... in the 2000 cSt range for external gear pumps.

 

[fraso]

Originally Posted By: George Bynum
I wonder, however, if their statement wasn't to aim for a viscosity of NOT LOWER THAN 13 cSt at the oil's operating temperature"

Perhaps but my impression from our conversation was that 13 cSt was a target rather than a lower limit.

If we were to use your viscosity range recommendation, the recommended AW46 would be suitable from ~43°C to ~69°C and AW32 would be suitable from ~34°C to ~60°C.

What risks would there be in running a higher or lower viscosity grade (than optimum) oil in log splitter's hydraulic system?

 

[George Bynum]

Originally Posted By: fraso
If we were to use your viscosity range recommendation, the recommended AW46 would be suitable from ~43°C to ~69°C and AW32 would be suitable from ~34°C to ~60°C.

What risks would there be in running a higher or lower viscosity grade (than optimum) oil in log splitter's hydraulic system?
First, rather than "suitable" I'd rather say "optimal".

I recommend selecting viscosity based on temperature, "32cSt if operating temperature is about 45C" , "46cSt if operaing temperature is about 55C" , "68cSt if operaing temperature is about 55C". My numbers fully accept +/-5C.

Too thin ... film breaks down, wear increases
Too thick ... efficiency down, way too thick, other issues
Too cool (under 40C for me) ... condensation
Too warm (over 65C for me) ... too rapid breakdown of fluid.

LET ME EMPHASIZE ... ALL GENERAL STATEMENTS ARE FALSE including these.

So ... 68cSt in a system where fluid temperature is 40C, loss of efficiency, higher filter pressure drop (linear) ... not much else

32 cSt in a system operating at 65C ... more likely to have metal wear from film breakdown. Premium fluids help here somewhat.

Remember that I am primarily involved in industrial applications where we actually attempt to control operating temperature ... a goal of +/-2C on a given machine is not unrealistic. EMPHASIS ... this is repeatability, not accuracy ... 5 machines, different machines, may have 5C different reservoir temperatures REAL, but each is kept close. So many speed controls (flow) are open-loop and today and next week need to be similar.

And yes ... changing tooling from machine to machine often has problems requiring customization.