hydraulic res size?

saiga · May 13, 2009

im using a 12 gpm prince pto pump to run a home made (kind of) backhoe . i have an 11 gallon reservoir. is that cutting it too close? does anyone know where to get inexpensive tanks. any thoughts welcome

J_J · May 13, 2009

saiga said:
im using a 12 gpm prince pto pump to run a home made (kind of) backhoe . i have an 11 gallon reservoir. is that cutting it too close? does anyone know where to get inexpensive tanks. any thoughts .welcome

I believe your tank size is supposed to be 2 times the pumps GPM. So if your pump is 12 GPM, you need a 24 gal tank. However, if you have a small radiator with fan, you can run the return fluid through the radiator be fore dumping into tank.

I believe Surplus Hydraulics has tanks, and Baileynet.com

https://www.surpluscenter.com/home.asp

http://baileynet.com/index.php

kennyd · May 13, 2009

saiga said:
im using a 12 gpm prince pto pump to run a home made (kind of) backhoe . i have an 11 gallon reservoir. is that cutting it too close? does anyone know where to get inexpensive tanks. any thoughts welcome

11 GPM reservoir for a 12 GM pump is a great match. The "ideal" setup is to match the 1:1, but you are so close it does not matter. Most consumer grade logsplitter's for instance have very small resivoirs.

kennyd · May 13, 2009

J_J said:
I believe your tank size is supposed to be 2 times the pumps GPM. So if your pump is 12 GPM, you need a 24 gal tank. However, if you have a small radiator with fan, you can run the return fluid through the radiator be fore dumping into tank.

I believe Surplus Hydraulics has tanks, and Baileynet.com

https://www.surpluscenter.com/home.asp

Bailey Hydraulic Cylinders Manufacturer

Sorry JJ, that is incorrect- Ideal setup is 1:1 ratio, not 2:1.

MichiganIron · May 13, 2009

It wasn't that long ago that the common design rule was to size the reservoir at 2:1. Recently, the rule of thumb has moved to 1:1. Most of the hydraulic fluids today contain additives that allow the 1:1 design. Just make sure your return lines are sized to slow the return flow to around 3fps.

Brad_Blazer · May 13, 2009

"24 gal tank."
All I can think of is $150 worth of oil!

J_J · May 14, 2009

Don't you think a 1:1 is kind of illogical. The most important part of a hydraulic system is the fluid, and the temperature of the oil, very important. The turn around time for the oil in a 1:1 doesn't give time for the heat to dissipate, expunge the air, or let contaminants settle. While it is true that hydraulics in mobile hydraulic systems have shrunk, The object was to save space, and doing so, they expect the system to be a little bit more heat tolerate. I also have not seen the 1:1 ratio mentioned very much, while I have seen the others, such as 2:1 and 3:1 . I can understand that certain systems could get away with small tanks, when the system is using intermittent hydraulics. Working a pump at 100 % . I think the the 2:1 or better will give more longevity to the system.

That is my take on it, the less heat you have, gives a better operating system for the hydraulic fluid.

What ever one wants to do , he can, he is the project manager.

wedge40 · May 14, 2009

Here it states 3 to 5 time the flow rate. (Cha-Ching)

http://www.hydraulicsupermarket.com/upload/db_documents_doc_10.pdf

But I'm guessing they are talking some pretty big equipment and in constant use. I've asked this question before and have decided for me 1:1 or maybe even a little less will be adequate. I figure I could always place a temp gauge on the system to keep an eye on it. How big are the reservoirs and pumps that come with the self contained backhoes like Woods? I'm also guessing that the larger the diameter of the cylinders being used the more heat generated during use. Ok the more volume of heat produced and therefore larger tank required.

Wedge

jenkinsph · May 14, 2009

As JJ mentioned the heat is a major concern, so if you wan't to conserve space and size of the tank you may need an oil cooler. I would definitely have a temperature guage to monitor the system. You can get by with a 1:1 system as long as the oil remains cool enough but I would prefer a 2:1 setup.

Steve