Splitting Force of Wood
Splitting Force of Wood
(OP)
Im trying to get a splitting force required for wood with as Strength in Shear at 2660 psi. The Log i'm calculating for is 16" Diam. and 20" long. Im ending up with like 851000 lbs required to split which seems really high.... Does anyone know if this is right...I dont think it is





RE: Splitting Force of Wood
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
RE: Splitting Force of Wood
What you are interested in is the tensile strength perpendicular to the grain. For Douglas fir it is 2 MPa.
h
Ted
RE: Splitting Force of Wood
Cheers
Greg Locock
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RE: Splitting Force of Wood
http://ww
Ted
RE: Splitting Force of Wood
RE: Splitting Force of Wood
http://www.thestickler.com/article.asp?id=5833
RE: Splitting Force of Wood
As pointed out by hydtools, you are interested in the tensile strength perpendicular to the grain.
As you drive a wedge in parallel to the grain you are developing tensile forces perpendicular to the grain.
RE: Splitting Force of Wood
RE: Splitting Force of Wood
http://www
Lots of information on the fracture of wood.
http:/
RE: Splitting Force of Wood
see:
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for some examples.
RE: Splitting Force of Wood
Ted
RE: Splitting Force of Wood
RE: Splitting Force of Wood
I think this is the Patent description for the machine you showed.
http:
If this is what you are doing, you are splitting on 3 planes across the end face of the log simultaneously.
If this is, in fact, what you are trying to do, you are going to have a hard time getting an exact figure, because of the interactions of several splits occuring at the same time.
B.E.
RE: Splitting Force of Wood
RE: Splitting Force of Wood
Hyd Tools and Mint Julep have pretty much called what you need.
Do you have a bursting cone on the front of the blades?
Maybe you should analyze the force for the cone using the tensile strength perpendicular to the grain for the wood you are using.
If you do not have a cone, then doubling the force you got with one knife should give you enough to start the split then the forces should reduce.
B.E.
RE: Splitting Force of Wood
The one I observed had a 56 hp diesel engine with a stacked pump(2). I don't think the pump was two stage. The pressure gauge was not working on this unit due a leak.
The ram was rated at 33 tons. I have a single wedge 26 ton splitter with a 8.5 hp gas engine that struggles with a large diameter log. The log processor had no problems with large logs, max was 28"dia x 24" long. It was capable of using 4,6,or 8 blades.
The flow rate of the pump was quite high as the forward stroke while cutting was quite high. It seem to keep the same speed despite the number of blades. The blades on the cutter head are not in the same plain as each is set back from a 1/8" to 1/4" from each other. The key to fast operation was that the splitter head had to be centered on the log. The cylinder appeared to be 4" cylinder with a oversize piston rod.
The higher hp and large pump really increase the speed of each stroke as compared to my single. The owner of this log processor stated that he was going to upgrade to a 66 hp engine to speed up processing.
RE: Splitting Force of Wood
Some of the rental units advertise between 5 tons and 22 tons of force.
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
RE: Splitting Force of Wood
As for splitting, where's the fun in a hydraulic splitter? You aren't a real man unless you've spent a summer splitting 36" cottonwood boles with a maul and wedge + sledge. Wussies.
:)
RE: Splitting Force of Wood
While a hydraulic cylinder must be able to generate sufficient force to start a split, the work required will determine the engine size. A maul or sledge is an energy storage device and the force it generates is determined by the wood itself. You have no idea how much force it hits with without measuring instruments but it real easy to tell how much work you are doing!
RE: Splitting Force of Wood
If you look at the offerings you will see subtle differences in each approach.
https://sawmillmag.com/Go.BGListings?c=21
tomwalz,
One of the processors even uses a circular chop saw in place of a chain saw. They say keep cutting instead of sharpening chains.
RE: Splitting Force of Wood
Thanks for the mention. Glad you are doing well. Chain saws are popular because they are smaller with less mass to move up and down. The big cut off saws (sometimes Scragg saws) use inserted teeth and we never found much of a market there.
Dear btrueblood,
As, I would bet you well know, snipping logs is not such a good idea. The force is possible but you destroy the log. Weyerhaeuser looked at it and decide that they lost way too much wood fiber. I would be you would pretty well destroy a 20” long log, 16” in diameter. I’d love to see a video of it.
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
RE: Splitting Force of Wood
But you are right, the new Deere harvester with the tracks in front uses a cutoff saw (or a mounted chainsaw?), not a snip. Neat machines, I want to find one working and watch it for awhile. Unfortunately, most of the logging areas around here are also on steep hillsides where that machine, and others like it, would make a mess as is rolled 1000 feet down thru the woods...
RE: Splitting Force of Wood
Modern Marvels has a show called Logging Tech where they show one working a little bit.
There is a forestry show in B.C. where they take folks out in the field and watch machines work.
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
RE: Splitting Force of Wood
The fact that y'all are still in business here where loggers and mill workers are an endangered species, means your company must do pretty darn good work. If I ever need some carbide, I know where to look.
RE: Splitting Force of Wood
I know I would need weight of the maul and most likely the velocity.
RE: Splitting Force of Wood
http://em
Ted