Broke the input shaft on my hydraulic pump.. what is a good one to buy to replace this one? I'm running a 14 hp gas motor, 5 inch bore splitting cylinder and a hydraulic chainsaw.. I think the one I had was 21 gpm not sure of the brand, it does not have a id tag on it.. thanks!
Recommend a pump for my processor
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I don’thave the file here, but search online to find the diagram for calculating displacement of a gear pump. By measuring across the gear set in two directions, and the width of the gears, you can determine cubic inches per revolution. The formulas are really close and gear pitch doesn’t affect them much.
Once you know CIR, picking a pump with rotation direction, mount, and other features is fairly easy.
I assume it is a single section pump as a two stage would do bad things with an overrunning saw motor load. Are the two loads in series, power beyond valves? Or is it two separate gear sections, one for cylinder and one for saw motor?
Why did the shaft fail? Huge pressure spikes? Metal through it jammed gthe gears? Or side load on the shaft, which is the most common cause. How many hours?
I don’thave the file here, but search online to find the diagram for calculating displacement of a gear pump. By measuring across the gear set in two directions, and the width of the gears, you can determine cubic inches per revolution. The formulas are really close and gear pitch doesn’t affect them much.
Once you know CIR, picking a pump with rotation direction, mount, and other features is fairly easy.
I assume it is a single section pump as a two stage would do bad things with an overrunning saw motor load. Are the two loads in series, power beyond valves? Or is it two separate gear sections, one for cylinder and one for saw motor?
Why did the shaft fail? Huge pressure spikes? Metal through it jammed gthe gears? Or side load on the shaft, which is the most common cause. How many hours?
I've ran it for 5 years, not sure of the hours, probably 10 truck loads a year.. I have power beyond valves, it's a 2 stage pump, I was splitting twisted elm and it was in "low" gear almost the whole time.. the rubber part of the lovejoy coupling was wore pretty good but not completely wore out... I feel like it just had too much strain on it.. but not sure..
With a 14hp. engine if the engine is healthy you can run a 28 gpm 2-stage pump. If slightly worn a 22 gpm 2-stage will work. The 22 and 28 gpm 2-stage pumps use the same industry standard pump mount.
Check online for 2-stage log splitter pumps. Prices can vary widely for the same brand and size of pump. Concentric/Hadex and MTE are the major US brands. Most of the rest are imports.
Check online for 2-stage log splitter pumps. Prices can vary widely for the same brand and size of pump. Concentric/Hadex and MTE are the major US brands. Most of the rest are imports.
so just to be clear it is a two stage pump? One Inlet, one outlet? The reason I ask is I would expect it to be a two section pump with two outlets and then combining and unloading after the saw motor. an actual two stage pump is going to slow down the saw motor and unload the large gear section at 500 to 800 psi which maybe is fine maybe that’s all it takes to run the saw. but if it took more pressure than that the saw would slow down dramatically. if the saw motors large enough maybe 500 psi is more than enough horsepower that would be five or 6 hp.
the Barnes haldex concentric 22 and 28 pumps have the same small gear section so either one would take you to the same relief valve maximum pressure and same engine load. The large gear of course is bigger which means you have to set the unloading pressure slightly lower for the 28 pump. the 22 pump could go to a slightly higher pressure before unloading at the same engine horsepower. So you have to decide which of the two what your needs are and where it runs now for pressure and where you want to unload to slow speed high pressure.
the Barnes haldex concentric 22 and 28 pumps have the same small gear section so either one would take you to the same relief valve maximum pressure and same engine load. The large gear of course is bigger which means you have to set the unloading pressure slightly lower for the 28 pump. the 22 pump could go to a slightly higher pressure before unloading at the same engine horsepower. So you have to decide which of the two what your needs are and where it runs now for pressure and where you want to unload to slow speed high pressure.
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