Hydraulic motor reccommendations

[birddog0304]

Looking to run a 7 ft sickle mower from an 8-10 gpm hydraulic pump. Sickle mower was belt driven off a midmount pto.
What hydraulic motor (size) would be needed?
Thanks

 

[muddstopper]

I think that is going to be a hard question to answer. First, how many rpms does/did the input shaft turn that operated the cutter. What size belt pullies are on the shaft side and on the mower side of the gearbox. You need to know how many rpms are needed to make the sickel cycle at the correct speed. Next you will need to know how many horsepower it takes for the sickle mower to cut correctly. How many pto hp does your tractor have and does it cut with ease or does it seem to bog down the tractor in heavy grass. All of this needs to be taken into consideration when sizing a hydraulic motor for the application. You fit the hydraulic motor to the application and then you determine the size hydraulic pump to run it with. If you are stuck using the pump you already have, then I suggest you purchase the biggest hydraulic motor that your pump and engine combination will pull and hope for the best. You havent provided enought information to make a reasonable guess.

 

[birddog0304]

I think that is going to be a hard question to answer. First, how many rpms does/did the input shaft turn that operated the cutter. What size belt pullies are on the shaft side and on the mower side of the gearbox. You need to know how many rpms are needed to make the sickel cycle at the correct speed. Next you will need to know how many horsepower it takes for the sickle mower to cut correctly. How many pto hp does your tractor have and does it cut with ease or does it seem to bog down the tractor in heavy grass. All of this needs to be taken into consideration when sizing a hydraulic motor for the application. You fit the hydraulic motor to the application and then you determine the size hydraulic pump to run it with. If you are stuck using the pump you already have, then I suggest you purchase the biggest hydraulic motor that your pump and engine combination will pull and hope for the best. You havent provided enought information to make a reasonable guess.

Was on
1000 pto (21 tooth)
Pullies are 1 to 1
Tractor hp that it was on about 35 (will run with less)
Optimal tractor rpm +/- 1500

Going to
Pump 20 gpm with 45 hp engine

Didn't know what all info to include.

Thanks

 

[J_J]

If your tractor HP is about 35 then you can run a pump, pumping about 17 GPM.

If you want the hyd motor to run at about 550 rpm, then you would need a pump displacement of about 7 cu in.

If you are pumping 20 GPM's, then you need an 8.5 cu in motor running at 544 rpm.

 

[birddog0304]

Thanks JJ

That's what I was looking for

 

[J_J]

Keep in mind that you have to use your tractor's pump GPM to compute the displacement for the motor.

 

[Farmerford]

Bird Dog:

Is the hydraulic power source your tractor's system or is it a PTO pump? If it is the tractor's system, when determining output as JJ suggested, be sure you take into account any priority uses, such as power steering. And then realize that to get the full rated flow you will have to run the engine at (probably) full rated RPM. Sickle mowers have lots of shortcomings (I know because I have two) but they are pretty quiet and they don't take more than a horsepower or so per foot; hate to disturb the tranquility with a diesel engine running fast under light load.

 

[birddog0304]

Keep in mind that you have to use your tractor's pump GPM to compute the displacement for the motor


Is the hydraulic power source your tractor's system or is it a PTO pump? If it is the tractor's system, when determining output as JJ suggested, be sure you take into account any priority uses, such as power steering. And then realize that to get the full rated flow you will have to run the engine at (probably) full rated RPM. Sickle mowers have lots of shortcomings (I know because I have two) but they are pretty quiet and they don't take more than a horsepower or so per foot; hate to disturb the tranquility with a diesel engine running fast under light load.[/QUOTE]

I have a pto pump. Rated at approximately 20 gpm. I will need the tractor's system to run a hydr cylinder as well as steering.