metalmagpie

05-05-2015, 11:32 AM

Straightforward, but I want to doublecheck my thinking/math before I commit the $$.

I want to make a hydraulic system powered by a 3hp 1750 rpm 182TC motor. I want 3000 psi max pressure. I need to know what pump to buy. I'm willing to take whatever flow rate I get. (I believe that the product of PSI and GPM is proportional to HP thus the larger the PSI rating the smaller the GPM for a given horsepower.)

I figure I should buy a gear pump. They are easy to understand and (I believe) cheaper and for my application should well outlast my lifetime and perhaps a few more. However, I don't fully understand the tradeoffs. Should I be looking for a vane pump or piston pump? Why?

Working through the math, I come up with the result that I should order a gear pump with displacement of 0.19 cubic inches per rev and of course max pressure rating of 3000 psi or above, ideally rated for use at 1800 rpm. Did I get the math right?

There don't seem to be a whole lot of these. Surplus Center has one but it is designed for 3450 rpm not 1750. This one: http://tinyurl.com/mxq9cnz Can I use this pump at 1750 without derating?

Finally, does anyone know a book or Web site that covers these questions and other practical aspects of hydraulic system design, pitched for an average engineer without graduate credentials in mechanical engineering?

Thanks!

metalmagpie

I want to make a hydraulic system powered by a 3hp 1750 rpm 182TC motor. I want 3000 psi max pressure. I need to know what pump to buy. I'm willing to take whatever flow rate I get. (I believe that the product of PSI and GPM is proportional to HP thus the larger the PSI rating the smaller the GPM for a given horsepower.)

I figure I should buy a gear pump. They are easy to understand and (I believe) cheaper and for my application should well outlast my lifetime and perhaps a few more. However, I don't fully understand the tradeoffs. Should I be looking for a vane pump or piston pump? Why?

Working through the math, I come up with the result that I should order a gear pump with displacement of 0.19 cubic inches per rev and of course max pressure rating of 3000 psi or above, ideally rated for use at 1800 rpm. Did I get the math right?

There don't seem to be a whole lot of these. Surplus Center has one but it is designed for 3450 rpm not 1750. This one: http://tinyurl.com/mxq9cnz Can I use this pump at 1750 without derating?

Finally, does anyone know a book or Web site that covers these questions and other practical aspects of hydraulic system design, pitched for an average engineer without graduate credentials in mechanical engineering?

Thanks!

metalmagpie