The Forestry Forum is sponsored in part by:

iDRY Vacuum Kilns


Forestry Forum
Sponsored by:


TimberKing Sawmills



Toll Free 1-800-582-0470

LogRite Tools



Norwood Industries Inc.




Your source for Portable Sawmills, Edgers, Resaws, Sharpeners, Setters, Bandsaw Blades and Sawmill Parts

EZ Boardwalk Sawmills. More Saw For Less Money!

STIHLDealers.com sponsored by Northeast STIHL


Woodland Sawmills

Peterson Swingmills

 KASCO SharpTech WoodMaxx Blades

Turbosawmill

Sawmill Exchange

Michigan Firewood, your BRUTE FORCE Authorized Dealer

Baker Products

ECHO-Bearcat

iDRY Wood Lumber Vacuum Drying for everyon

Nyle Kiln Dry Systems

Chainsawr, The Worlds Largest Inventory of Chainsaw Parts

Smith Sawmill Service



Author Topic: How big should my pump be?  (Read 2143 times)

0 Members and 1 Guest are viewing this topic.

Offline CX3

  • Senior Member
  • ****
  • Posts: 871
  • Age: 39
  • Location: SW Missouri
  • Gender: Male
    • Share Post
How big should my pump be?
« on: September 23, 2010, 10:47:29 PM »
Quick question.  I am building a firewood processor, and am putting a 36 inch stroke, 3 inch ram, 6.5 inch bore cylinder.  I need to know what kind of pump to get and what size to make this thing work rather fast.  I understand that my cylinder is pretty large, I could get a smaller cylinder but will be splitting oak six ways.  Also advice on an engine would be helpful also. 

I have access to a backhoe pump, but dont know what type of power will suffice.  Any advice appreciated. 
John 3:16
You Better Believe It!

Offline beenthere

  • Senior Member x2
  • *****
  • Posts: 27074
  • Location: Southern Wisconsin, USA
  • Gender: Male
    • Share Post
Re: How big should my pump be?
« Reply #1 on: September 23, 2010, 11:14:47 PM »
If you have a 25gmp pump, I calculate it will take about 12 sec to travel the 36".
That doesn't seem very fast.
And, that's a quick calculation. About 5 gal of oil in the extended cylinder.

What size pump do you think you can get ahold of?

How fast do you want the stroke?

south central Wisconsin
 It may be that my sole purpose in life is simply to serve as a warning to others

Offline Gary_C

  • Senior Member x2
  • *****
  • Posts: 7122
  • Age: 79
  • Location: Blooming Prairie, MN USA
  • Gender: Male
  • Sunrise on the Prairie
    • Share Post
Re: How big should my pump be?
« Reply #2 on: September 23, 2010, 11:22:53 PM »
I need to know what kind of pump to get and what size to make this thing work rather fast. 

Define rather fast first. Then you have two different cycle times to consider.

First the out or pressure stroke. Find the area of the piston times the stroke length and you have the number of cubic inches of hydraulic fluid to move and divide that number by the time you wish to run that cycle. By my calculations you have 1194.6 cubic inches for a full stroke and if you want to complete that cycle in say 6 seconds you will need 11946 cubic inches or 51.7 gallons per minute of pump capacity. (231 cubic inches per gallon) That's going to be hard to do with most pumps you will find as that's a big pump.

Then you must do the same for the return cycle but remember to subtract the diameter of the rod from the volume needed. So the return cycle will be faster.

Now that should give you the tools to do the calculations and adjust from there. You may not want to consider a full length cycle as you most likely do not need the full 36 inch stroke each time. And there are two stage pumps that can pump at a higher rate when not under much load.

Then after you do those calculations, the max pressure you will need will determind the HP required to spin that pump and of course you will also need to consider the hose size to carry that much hydraulic fluid.
Never take life seriously. Nobody gets out alive anyway.

Offline sprucebunny

  • Senior Member x2
  • *****
  • Posts: 4134
  • Age: 67
  • Location: Northern NH
  • Gender: Female
    • Share Post
Re: How big should my pump be?
« Reply #3 on: September 24, 2010, 08:33:29 AM »
Here's a calculator.

http://www.surpluscenter.com/Hydraulic.htm

You can search for other calculators.
MS193, MS192 and an 026  Weeding and Thinning. Gilbert Champion sawmill

Offline CX3

  • Senior Member
  • ****
  • Posts: 871
  • Age: 39
  • Location: SW Missouri
  • Gender: Male
    • Share Post
Re: How big should my pump be?
« Reply #4 on: September 24, 2010, 09:16:51 PM »
OK.  After running all over town today and asking questions I am going to use a 5 inch bore, 24 inch stroke cylinder.  With a 22gpm two stage pump.  The calculator says I need a 90hp gas engine to run it.  I was hoping for a smaller engine size. 
John 3:16
You Better Believe It!

Offline Gary_C

  • Senior Member x2
  • *****
  • Posts: 7122
  • Age: 79
  • Location: Blooming Prairie, MN USA
  • Gender: Male
  • Sunrise on the Prairie
    • Share Post
Re: How big should my pump be?
« Reply #5 on: September 25, 2010, 12:04:54 AM »
There is something wrong with your calculator. That pump should not need that much horsepower. I'd say 10-15 max.
Never take life seriously. Nobody gets out alive anyway.

Offline Larry

  • Senior Member x2
  • *****
  • Posts: 6557
  • Age: 73
  • Location: NW Arkansas
  • Gender: Male
    • Share Post
    • Copas Sawmill
Re: How big should my pump be?
« Reply #6 on: September 25, 2010, 05:49:27 AM »
I built a 3-point splitter for the tractor using a 5" X 30" cylinder.  Put it on a JD 4030 which has 23 gpm flow and 80 HP.  Operation speed was quite reasonable.  Sold all my farm tractors and the only thing I have around now is a Ford 1720.  Flow is 7 gpm with 27 HP or so.  The splitter still has the same amount of power but now I can take a nap while the cylinder extends. :D

Gary's power estimate seems in the ball park.
Larry, making useful and beautiful things out of the most environmental friendly material on the planet.

We need to insure our customers understand the importance of our craft.

Offline madmari

  • Senior Member
  • ****
  • Posts: 299
  • Age: 60
  • Location: Northwest VT
  • Gender: Male
    • Share Post
Re: How big should my pump be?
« Reply #7 on: September 25, 2010, 08:28:53 PM »
90 HP outta fire the split wood through the wedge so fast you won't need an elevator; just park the truck about a hundred yards away and fire the wood into it. A 3/4" plate should stop the wood from going through the cab. ;D

  A two stage pump will make that size cylinder quite fast with a smaller motor. Very large processors are run with 18hp motors and 23 GPM pumps. 
I know why dogs stick thier head out the car window.


Share via delicious Share via digg Share via facebook Share via linkedin Share via pinterest Share via reddit Share via stumble Share via tumblr Share via twitter

xx
Diesel Primary pump from tank to injector pump

Started by Ironwood on General Board

19 Replies
3331 Views
Last post January 25, 2005, 08:12:11 PM
by Ironwood
xx
Enough pump??

Started by overclocking on Firewood and Wood Heating

5 Replies
727 Views
Last post February 16, 2016, 10:19:02 AM
by overclocking
xx
064 oil pump

Started by stan064 on Chainsaws

3 Replies
408 Views
Last post July 19, 2020, 06:49:44 AM
by thecfarm
xx
bad Pump?

Started by stumper on Firewood and Wood Heating

7 Replies
762 Views
Last post November 24, 2018, 07:26:48 PM
by doctorb
 


Powered by EzPortal