Pto rpm question

   #1  

Number15

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Rhea County TN
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Branson 5520CH, Grasshopper 928D2
Looking at power trac and diving in to the specs. I am considering a 1845 and I am wondering does the hydraulic pto run at 540 rpm like my tractor does? Or do hydraulic pto run a different standard?

Thanks
 
   #2  

SpringHollow

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The "PTO" is just a pair of hydraulic connectors on a high flow, high pressure circuit. You have to pick the appropriate hydraulic motor for an implement to get 540 RPM. This is not hard to do when adapting conventional PTO implements. Obviously, PT picks appropriate motors to get the right speed for their implements.

Ken
 
   #3  

agjones

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Jessup Mill, NC
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Rk55HC 4n1 fel/bh, Power-Trac 1850, 425d, Terex pt30, Honda 5013, yanmar 8x8 dumper, Magnatrac mh5000 w/ loader, six way blade & backhoe, Dew-eze MC70 Slope Mower, Terramite t6 4wd, DR Power brush mower
The mechanical pto of a tractor provides a shaft you connect to a gear box on an implement. In the US the shaft is generally rotating at 540, sometimes 1000 rpm. The gear box determines the implement rotation speed. Slow with high torque for an auger, fast with less torque for a mower...as examples.

The hydraulic pto of a power trac or skidsteer provides flow to a hydraulic motor on an implement. The displacement of the hydraulic motor determines the rotation speed of the implement.

You can power tractor implements w the power trac. Not all tools are a great fit, because of weight distribution, direction of operation etc.
 
  
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#4  
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Number15

Number15

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Location
Rhea County TN
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Branson 5520CH, Grasshopper 928D2
Ok so it's the hydraulic motor on the implement side that determines the rpm, correct?

I calculated the hp on the 1845 pto to be ~26. Does that seem right?
 
   #5  

ponytug

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Power Trac PT1445
Ok so it's the hydraulic motor on the implement side that determines the rpm, correct?

I calculated the hp on the 1845 pto to be ~26. Does that seem right?
Yes, it would be about 26HP; but hydraulic HP doesn't map perfectly to another tractor's performance of a given HP, since it isn't mechanically linked. In general, items like the PT mowers and tillers are quite fit for the intend use (I.e. the hydraulic flow generates enough HP to drive the mower motor at a normal speed). For adapting third party implements, you need to do the math, and then know your engine well enough to know where (in the rpm curve) you want the engine to be pumping the correct volume of fluid. It even works when you don't do the math and just need close enough.;)

The nitty-gritty is that you need the volume swept per revolution (e.g. cu. in./rev) of the given motor to compute the rpm. I adapted a WoodMaxx chipper needing a 540 rpm input to a hydraulic motor to be able to run of a PT easily. The hard bit was making a mounting plate to mount the motor into the chipper.

All the best,

Peter
 
  
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#6  
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Number15

Number15

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Rhea County TN
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Branson 5520CH, Grasshopper 928D2
Thanks for the replies.

If I get the 1845 I was thinking about getting a Lane shark and trying to adapt it. Has anyone else done that?
 
   #8  

ponytug

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Power Trac PT1445
Thanks for the replies.

If I get the 1845 I was thinking about getting a Lane shark and trying to adapt it. Has anyone else done that?
There is a whole thread here on that attachment that you might want to have a look at.

What are you wanting to accomplish with the tractor and mower? (It might help others give better advice.)

All the best,

Peter
 
 
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