How do you calculate digging force requirements?

   / How do you calculate digging force requirements? #1  

jgibbens

Bronze Member
Joined
Mar 23, 2011
Messages
68
Location
Hopedale, IL
Tractor
Kubota BX 25D
Is there a guideline for calculating the amount of force needed to push a digging implement into different types of soil?
 
   / How do you calculate digging force requirements?
  • Thread Starter
#3  
I need the other side of the equation. How much force does it take to push an implement into the ground? I'm almost finished with a hydraulic tree spade and took it out for a test run last night. The spade uses 2" bore cylinders to push blades made from 19" diameter pipe. They dig in about a foot before the hydraulics start to bypass. I really wasn't expecting 7,000 lbs of force to be insufficient so now I need to figure out how much force it should take before I buy larger cylinders.
 
   / How do you calculate digging force requirements? #4  
I can't help you, but interesting situation/ topic.

You are getting through the topsoil, hitting the subsoil. Often (here anyhow) the subsol is hard undisturbed yellow clay, very hard to push through. Amount of moisture also makes a big difference, right now it's probably like jelly. In August, it's probably like concrete.

Hard to get a real number, as it changes so much?

--->Paul
 
   / How do you calculate digging force requirements? #5  
I am pretty sure that I recall watching a program where a very large Semi mounted tree spade used water as a lubricant on the actual spades. The water was a critical part of the process. Without the water they couldn't get the depth of penetration needed.

http://www.treeservicesmagazine.com/print-2221.aspx
 
   / How do you calculate digging force requirements? #6  
That's true. If you try to push a grounding rod in by hand, you can't do it obviously. If you do the same thing and fill the hole with water while you wiggle it, you can drive a 6' grounding rod all the way into clay by hand. I've done it!

I'd look into using a small sprayer pump and reservoir with some perforated tubing wrapped around the tool to lubricate it.
 
   / How do you calculate digging force requirements? #7  
That's true. If you try to push a grounding rod in by hand, you can't do it obviously. If you do the same thing and fill the hole with water while you wiggle it, you can drive a 6' grounding rod all the way into clay by hand. I've done it!

I'd look into using a small sprayer pump and reservoir with some perforated tubing wrapped around the tool to lubricate it.

Sounds like a good idea to me. I don't know what you have this thing attached to, but it sounds like something needs to change or else you are going to need a REALLY heavy tractor.
 
   / How do you calculate digging force requirements? #8  
A little vibration can help with soil penetration. I'm thinking maybe a small eccentric spinning weight attached to the digger frame. Combine that with the water spray and you might have performance that meets your expectations.
 
 
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