Flow Question

[RFB]

Sirs,

I am sizing a hydraulic auger for my tractor (Kubota GL5740HSTC) on a QA FEL mount.

The flow requirements for the 2 models in consideration are:
6-15 GPM (McMillen X975)

and

10-25 GPM (McMillen X1475).

The difference in torque is considerable between the two:

X975 at 10gpm 1,500 lb-ft;

X1475 at 14gpm 2377 lb-ft (and 1600 at 10gpm)

My tractor specs show the following: "Implement pump 9.8 gpm; Power Steering Pump 4.9gpm; Total Hydraulic Flow 14.7 gpm"

My question is twofold:

1. Is the "Total Hydraulic Flow" potentially available for the auger if the tractor is not being steered, or is it always limited to the Implement pump 9.8 gpm flow?

2. If the flow is limited to the Implement pump 9.8 gpm flow, is it better to go with the X1475 to (theoretically) pick up the extra few pounds of torque at the bottom end (1600 versus 1500 hundred max for the X975)?

Thank you.

 

[oldnslo]

Sirs,

I am sizing a hydraulic auger for my tractor (Kubota GL5740HSTC) on a QA FEL mount.

The flow requirements for the 2 models in consideration are:
6-15 GPM (McMillen X975)

and

10-25 GPM (McMillen X1475).

The difference in torque is considerable between the two:

X975 at 10gpm 1,500 lb-ft;

X1475 at 14gpm 2377 lb-ft (and 1600 at 10gpm)

My tractor specs show the following: "Implement pump 9.8 gpm; Power Steering Pump 4.9gpm; Total Hydraulic Flow 14.7 gpm"

My question is twofold:

1. Is the "Total Hydraulic Flow" potentially available for the auger if the tractor is not being steered, or is it always limited to the Implement pump 9.8 gpm flow?

2. If the flow is limited to the Implement pump 9.8 gpm flow, is it better to go with the X1475 to (theoretically) pick up the extra few pounds of torque at the bottom end (1600 versus 1500 hundred max for the X975)?

Thank you.

I am 99% sure you only have the 9.8 GPM flow available for implements. The flow is going to provide RPM dependent on the motor displacement. The torque is a combination of the motor displacement and pressure.

McMillen sight states that at 10 GPM the X1475 will operate at 38 RPM and the X975 will turn at around 60 RPM.

So I guess it boils down to what speed do you desire and what type of soil are you going to be working in? Loose sand easy auger torque may not be an issue. Gumbo clay you probably want all the torque you can get and then some.

Roy

 

[grsthegreat]

I found out while researching about a loader mounted snowblower is that while tractors may have 8-10 GPH output available,

1. Its at 2,400-2,500 psi whereas skid steers are at 3,000 - 3,200 psi
2. Tractors store maybe 5 gallons of hydraulic oil available for use while skid steers can store 20 gal
3. The amount of available hydraulic reserve determines how HOT the hydraulic oil will get and hot oil = wrecked hydraulic pumps.


I went with a 3 point, rear mounted 20 gallon PTO powered hydraulic tank on my tractor to power skid mount equipment.

It boosts the psi to 3,000 and allows 20 gallons of flow for cooling.

I plan on adding a loader mount post hole digger in the near future also.

 

[J_J]

RFB,

Is your tractor capable of 3000 psi?

You really don't have the min for the X1475. I think the X975 would match your tractor better. There doesn't appear to be a large difference, except the price is probably greater, and the X1475 is rated for a larger auger .The rpm is not going to change the torque vary much, if any.


Model X975
maximum auger diameter 24" 610 mm
minimum hydraulic flow 6 GPM 30 LPM
maximum hydraulic flow 15 GPM 57 LPM
maximum continuous operating PSI 3000 PSI 207 bar
output shaft options 2" round 2-9/16" round 2" hex
output speed output torque
flow speed Pressure
GPM LPM RPM PSI Bar Lb-ft N-m
6 23 36 2000 141 1000 1356
8 30 47 2500 176 1277 1731
10 38 60 3000 211 1500 2034


Model X1475
maximum auger diameter 30" 762 mm
minimum hydraulic flow 10GPM 38 lpm
maximum hydraulic flow 25 GPM 95 lpm
maximum continuous operating PSI 3000 PSI 207 bar
output shaft options:
2-9/16" round 2" hex
output speed output torque
flow speed pressure
GPM LPM RPM PSI Bar Lb-Ft N-m
10 38 38 2000 138 1600 2169
12 45 45 2500 172 2000 2712
14 53 53 3000 207 2377 3223

 

[RFB]

Roy,

It is rocky, very rocky and I will be using a auger head similar to this:
McMillen Rock Ripper Auger Bits (was HDR Style) for your Skid Steer, Skidsteer, Hydraulic Drive Auger Unit in 2" Hex shaft size, 48" length


gtg,

I agree in principle regarding the heat issues re. fluid reservoir capacity. That being said, this will not be a steady-state duty like a blower. This will be drill a hole and reposition, drill and hole and...

JJ,

Thank you for the insight.

 

[oldnslo]

Roy,

It is rocky, very rocky and I will be using a auger head similar to this:
McMillen Rock Ripper Auger Bits (was HDR Style) for your Skid Steer, Skidsteer, Hydraulic Drive Auger Unit in 2" Hex shaft size, 48" length


gtg,

I agree in principle regarding the heat issues re. fluid reservoir capacity. That being said, this will not be a steady-state duty like a blower. This will be drill a hole and reposition, drill and hole and...

JJ,

Thank you for the insight.

If it is very rocky the slower speed and higher torque of the X1475 might be an advantage. The torque provided is a function of pressure and not flow so you should obtain the xxx ft/lbs of torque at 20 RPM. Would suggest also looking at your supply line sizes to make sure they don't add any significant pressure drop loss. That is all wasted energy/heat also.

What torque will your loader frame stand before it starts to twist?

best of luck

Roy

 

[RFB]

OnS,

Sir,

"...supply line sizes..."

I invariably use at leat 1/2" and will be runing this to rear remotes from the FEL. Would you suggest larger? (The remote QC's are 1/2 but that is a momentary restriction; the biggest friction loss will be the run from the remotes to the FEL.)

"What torque will your loader frame stand before it starts to twist?"

I would not even begin to know how to answer that. It is a Kubota LA854, this system will be attached SSQA fashion spanning the FEL and torsion tube with the auger centered.

 

[oldnslo]

OnS,

Sir,

"...supply line sizes..."

I invariably use at leat 1/2" and will be runing this to rear remotes from the FEL. Would you suggest larger? (The remote QC's are 1/2 but that is a momentary restriction; the biggest friction loss will be the run from the remotes to the FEL.)

1/2" hose would be around 2 PSI per foot loss so figure round trip 50 ft of hose or 100 PSI. I doubt you will even notice this loss. Was concerned you would try to save a buck and use 1/4 or 3/8 hose & then complain because it runs to slow, has no torque, etc...

Torque wise: My guess is you will be fine, but that is just my guess. Does Kubota, or everything attachments have any recommendations on models for this loader.

Roy