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gerotor volume, RPM and displacement

gerotor volume, RPM and displacement

gerotor volume, RPM and displacement

Hello all,

Hello all,

I am working with a gerotor that I have no information about. It is a custom gerotor. I have the gerotor part with me and i was hoping to measure the volume of the fluid gerotor can dispense from the part I have. Can someone please explain to me how I can measure the volume of the fluid the gerotor dispenses? Plus how can I measure the RPM and Torque of the gerotor?


RE: gerotor volume, RPM and displacement

Yes it is because I am not sure if automotive folks can see my post on the other forum. I was hoping to expand to my search.

RE: gerotor volume, RPM and displacement

If you are going to do that, please reference the cross post in your original post. You dilute the answers when you have two posts going.

You are judged not by what you know, but by what you can do.

RE: gerotor volume, RPM and displacement

I imagine you would measure the cross-sectional area of the space between the rotor "teeth" at maximum volume minus minimum volume times rotor thickness times RPM etc.

The trick would be how to accurately measure this volume between the teeth. I would suggest scanning and copying the gears - then blow them up maybe by 10X - print out the result - measure the area on squared millimetre graph paper - then divide the result by ten.

RE: gerotor volume, RPM and displacement

If you have both pump elements, you can get a rough approximation by using measurement of a liquid volume required to fill the individual max/min working spaces. Or if you have access to a digital optical comparator, you can generate a set of points that can be used to create accurate 2D CAD geometry of the working surfaces. These can then be used to calculate the max/min volumes of the individual working spaces.

If you need an accurate volumetric flow rate of your gerotor design, you will also need to know the exact inlet/outlet port geometries, clearances/gaps between all the pump working surfaces, fluid characteristics, operating conditions, etc. The volumetric efficiency of the pump can be greatly affected if there are excessive gaps/clearances between the pump elements/housings combined with high pressures.

Here a basic technical reference on design of gerotor pumps: www.1130cc.com/forums/attachment.php?attachmentid=...

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