BX25 Mid PTO Pump or BUST

[magicheater]

If you can get an rpm vs HP curve for your engine from Kubota [I know they have it], then we know how much HP is available from the engine at each point in the range. If we know the reduction ratio of the mid pto it tells us what rpm the pto turns at any chosen engine rpm. Blending these info streams will let us determine how much power is available from pto at every ptorpm. That and the pump table will enable us to see if 3 kpsi can be sustained somewhere in the rpm range with your engine and any given pump. It may be that we find your engine running 1750 rpm will turn that pump against a 3kpsi pressure. We know from the table it wont do it at the engine rpm corresponding to 2500pto speed.
larry

Is what you are saying that at a lower RPM of PTO/Engine speed more power may be available at that speed? Then at the max Engine/PTO RPM you would have max flow but not max pressure? Finding the sweet spot may be critical then as to what sort of implement may be able to be powered by this configuration, as many are flow oriented but power sensitive?

 

[Artisan]

Larry the following is from HERE

D902-ET02 is what the sticker on my engine says...FWIW

There are 2 performance curve graphs, one to 3600 RPM and one to 3200RPM.

I do not quite understand why unless there are 2 versions of the same engine.
I believe mine goes to 3200 RPM. I would suggest the 3200RPM graph is correct...

 

[Artisan]

...and I found the following HERE;

 

[SPYDERLK]

Is what you are saying that at a lower RPM of PTO/Engine speed more power may be available at that speed? Then at the max Engine/PTO RPM you would have max flow but not max pressure? Finding the sweet spot may be critical then as to what sort of implement may be able to be powered by this configuration, as many are flow oriented but power sensitive?

Very quick mind dump then bed for me. Possibilities exist for 3000psi even if you cant do it at the rpm corresponding to full eng power because required pump drive torque is constant at a given pressure regardless of the rpm you drive it, but engine torque is not constant. Peak engine torque is always below the rpm where max HP is made by the engine. As rpm drops below that the torque rises some to a very flat curve at a slightly higher level. This causes engine power to fall off less quickly than the HP demanded by the pump. Thus higher pressure will be available below the engines max rpm. We need the real figures to see what we might be able to squeeze out.
larry

 

[SPYDERLK]

Larry the following is from HERE

D902-ET02 is what the sticker on my engine says...FWIW

There are 2 performance curve graphs, one to 3600 RPM and one to 3200RPM.

I do not quite understand why unless there are 2 versions of the same engine.
I believe mine goes to 3200 RPM. I would suggest the 3200RPM graph is correct...

Those show the torque and HP. Its what we need on the engine. That is very good. What eng rpm is 2500pto? Talk tomorrow.
larry

 

[magicheater]

Very quick mind dump then bed for me. Possibilities exist for 3000psi even if you cant do it at the rpm corresponding to full eng power because required pump drive torque is constant at a given pressure regardless of the rpm you drive it, but engine torque is not constant. Peak engine torque is always below the rpm where max HP is made by the engine. As rpm drops below that the torque rises some to a very flat curve at a slightly higher level. This causes engine power to fall off less quickly than the HP demanded by the pump. Thus higher pressure will be available below the engines max rpm. We need the real figures to see what we might be able to squeeze out.
larry

So matching the torque output of the engine to the torque (resistance) of the pump is very critical to the success of the system?

 

[hddnis]

Actually, Im thinking you may may missed that his tractor is rated at 17PTOHP. All those implements are rated above that. Can those implements operate ok at 80% flow or is full rated speed a must? OP can pump around 9+gpm at close to 3kpsi.
BTW Bobcat vs Ditchwitch figures do not compare correctly. ... one or both are wrong.
larry

Nope, didn't miss that at all. His mid PTO HP in this case is a duty rating, but not the max limit of available power. A MMM will far exceed the 17HP rating a small percentage of the time. So when designing a system driven by the PTO it is acceptable to use max engine HP. Even more so when talking about implements that will be used while the tractor is stationary. I thought I had mentioned that a few posts back, but now that I look I see that I forgot that paragraph.:ashamed:

As to Bobcat and Ditchwitch figures, they are of course wrong as they are a Bobcat and a Ditchwitch. Brand preference aside, those are the published specs from the manufactures website. You can look for yourself...

Here:
Ditch Witch - Compact Utility Tractor, Mini Skid Steer - Compact Tool Carrier - Ditch Witch SK350

and here:
MT52 Mini Track Loader - Bobcat Company



Mr. HE

 

[Artisan]

Man I so can't wait for my connectivity problems to be resolved...

Larry the 2500 number is the mid PTO that I want to use.

The engine spins up to 3200 .

 

[J_J]

I have to ask if this is a temporary connect to mid PTO setup, or a permanent type setup?

Along with the pump, you will need a valve and reservoir, filter and hoses.

Will this setup be easy to remove?

You might consider just a plug and play pump setup, and only use it when you have a use for it.

You might be able to make this pump/valve setup in a kit form and sell it, or sell plans for same.

Something like this would increase my log splitting speed from my tractor, a Kubota B9200.

 

[Artisan]

I have to ask if this is a temporary connect to mid PTO setup, or a permanent type setup?

Along with the pump, you will need a valve and reservoir, filter and hoses.

Will this setup be easy to remove?

You might consider just a plug and play pump setup, and only use it when you have a use for it.

You might be able to make this pump/valve setup in a kit form and sell it, or sell plans for same.

Something like this would increase my log splitting speed from my tractor, a Kubota B9200.

J_J If a guy wanted to leave it on, he can leave it on, if he wants to pull it
off he can pull it off. I am not welding anything to frame, if I can help
it.

I have drawn a 10.25 gallon tank that should install in about 4 minutes
maybe less. It is looking really nice. The pump can be swapped in and out
if a guy pleases in prob about the same, add however long it takes to
connect hoses. If you spend a small fortune on QD's it might be fast,
and it is looking like I will need a small fortune to pull this off. One piece
at a time, indeed I pulled the trigger, were going to see something
happen, more later than sooner simply due to money. I shutter to guess
what a professional tank builder is going to charge me for a .25 thick
aluminum tank w/ baffles doubling as vertical stiffeners in case of belly-rub
and a 2" bung for a strainer and 3 maybe 1" bungs for filler, and two
returns. Brackets, bash edging, bracketry and gussets, then buy 10
gallons of oil, hoses, filter, valve(s) yes plural, flow control and I want
one valve foot controlled so all hands are free to deal w/ the tractor so
perhaps if you hang an auger off the front your hands are free to keep it
plumb. Did I mention buying prob a case of 3/4" QD's?

Again I now know enough to be dangerous, , but effective. I have been
drawing circuits and redrawing and really trying hard to come up w/ a
system that is SAFE and quick in and out. Yes, valves and pressure relief
and Power Beyond and Flow Control and Strainer and Filter on and on
are all on my mind, it is all doable. If I pull this off I honestly think I will
have a KILLER attachment, that will run a LOT of stuff. If I can cram
10 pounds of sugar into a 5 pound BX25 sugar container it should be a
breeze for anything larger.

There is no doubt in my mind that I will make unit ALPHA, and DELTA will
be thought about as APLHA is switched on for the first time. The
possibilities are endless.

As far as selling it or the plans, I have not thought about it. That might be tough, it is going to be
expensive. The owners of this board need to be taken into consideration
as well. Profits right off the top go to them, if sold thru here and there
may not be any meat left for a seller, unless it sells for high dollar. Of
coarse you will be the first person to get a set of plans if there ever are
any, gratis, as well as a couple others, J_J.

After I finish one system, and it is up and running and no bugs,
if you run into anyone in SO Calif that has a Kubota B9200 I can try to
get with them and design bracketry to fit. Thats another thing,
this concept will work w/ any Mid-PTO equipped tractor but each frame
is different, that means each pump hanger, drive shaft, tank bracketry,
placement of valves and hoses will all be different, weather it is a hi/lo
pump or other, no matter, each frame is different and I would need
each tractor at my disposal near my computer to fit to it.

My computer is prob going to be down for a few days...