Morning everyone,
Because I need to consider the pump, loader spools as well as backhoe spools, I decided to come at this problem by gaining a basic understanding of hydraulics. I conclude there is no 1 size fits all. It is dependent on the size of and quantity of cylinders and therefore the total volume used and the max speed of which one want it to move. I am sharing the information I found in case others are trying to deal with it. The information comes from he Cylinder Pressure Chart from Baum Hydraulic Corporation.
The workup I have so far done is based on the 102 Davis loader and not the 185 backhoe. For the moment, I am assuming that the cylinders are either original or replaced with original spec'd parts. I will confirm this in the next day or two.
A major consideration is speed of lift.unit. looking around at new loaders, 3 to 5 seconds are some lift speed ranges. I am going to use 5 for now.
On the 102 loader
The bore of the lift cylinder is 2 1/4" (which is 3.97608 sq in)
The Stroke is 31"
3.97608 square inches x 31 (stroke) = 123.25848 cubic inches
to covert to gallons divide by 231 = .533586 gallons per lift cylinder.
.533586 x 2 lift cylinders = 1.067172 gallons to go to full extension
1. Speed 5 seconds
2. 1.067172 gallons (for both lift cylinders)
3. 1.067172 divided by 5 (speed) = .213434 gallons per second
4. .213434 X 60 (to get GPM) = 12.8 gallons per min
If I go with a joystick then I will need to also consider the dump requirements
4.909(sq inches) X 15.1875 (stroke) divided by 231(to get to gallons X 2 (2 dump cylinders) divided by 4 (speed for full extension of cylinders) X 60 (to ge GPM) = 9.68 GPM
Horsepower requirements
GPM X PSI divided by 1714 = HP required
One of the factory specs shows 17gpm at 2150 psi
That requires 21.3 HP to run the pump.
For myself I have not yet concluded what I am going to do. I need to understand the backhoe requirements.
Don
Because I need to consider the pump, loader spools as well as backhoe spools, I decided to come at this problem by gaining a basic understanding of hydraulics. I conclude there is no 1 size fits all. It is dependent on the size of and quantity of cylinders and therefore the total volume used and the max speed of which one want it to move. I am sharing the information I found in case others are trying to deal with it. The information comes from he Cylinder Pressure Chart from Baum Hydraulic Corporation.
The workup I have so far done is based on the 102 Davis loader and not the 185 backhoe. For the moment, I am assuming that the cylinders are either original or replaced with original spec'd parts. I will confirm this in the next day or two.
A major consideration is speed of lift.unit. looking around at new loaders, 3 to 5 seconds are some lift speed ranges. I am going to use 5 for now.
On the 102 loader
The bore of the lift cylinder is 2 1/4" (which is 3.97608 sq in)
The Stroke is 31"
3.97608 square inches x 31 (stroke) = 123.25848 cubic inches
to covert to gallons divide by 231 = .533586 gallons per lift cylinder.
.533586 x 2 lift cylinders = 1.067172 gallons to go to full extension
1. Speed 5 seconds
2. 1.067172 gallons (for both lift cylinders)
3. 1.067172 divided by 5 (speed) = .213434 gallons per second
4. .213434 X 60 (to get GPM) = 12.8 gallons per min
If I go with a joystick then I will need to also consider the dump requirements
4.909(sq inches) X 15.1875 (stroke) divided by 231(to get to gallons X 2 (2 dump cylinders) divided by 4 (speed for full extension of cylinders) X 60 (to ge GPM) = 9.68 GPM
Horsepower requirements
GPM X PSI divided by 1714 = HP required
One of the factory specs shows 17gpm at 2150 psi
That requires 21.3 HP to run the pump.
For myself I have not yet concluded what I am going to do. I need to understand the backhoe requirements.
Don