Impact Force of a JackHammer 3

[BuonGiorno]

What is the best way to calculate Impact Force per Blow given a jackhammer's weight, BPM (Blows per Minute), and Stroke Length? For ,example Ingersoll Rand JH40C3 has a Stroke Length of 67mm, BPM of 2000, and a weight of 27.7 kg.
I was thinking to use F=(0.5MV^2)/2 or F=(MV)/T ,but I am curious to see answers from others. Ingersoll Rand stated this is not information that they provide.

 

[IRstuff]

The article clearly requires the stopping distance, which is almost entirely dictated by the material being hit

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I can do absolutely anything. I'm an expert!

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[hydtools]

"I was thinking to use F=(0.5MV^2)/2 or F=(MV)/T"

The first equation is 1/2 kinetic energy.
The second equation is impulse-momentum.

Was not sure how to answer. Chose energy.

Ted

 

[IRstuff]

Doesn't matter; stopping distance can be correlated to stopping time.

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I can do absolutely anything. I'm an expert!

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[mfgenggear]

The stroke of the chisel would be the distance.
Shouldn't this also apply for an impact wrench?
My suggestion would be to reverse engineer
A jack hammer.

 

[IRstuff]

NO, it's not

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I can do absolutely anything. I'm an expert!

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[mfgenggear]

Look at this

https://www.explainthatstuff.com/jackhammer.html

 

[Compositepro]

mfgenggear, the links you are posting are not very relevant to answering the OP's question. You are getting distracted about details of how jackhammers are designed rather than understanding the concept of how impact force is created at the tip of a chisel when hit by a hammer. This is a very important concept to clearly understand, in many fields of engineering and everyday life. It seems a simple concept at first, but it is pretty complicated to understand the the first time one tries to figure it out. This is why this question keeps coming up. If one takes the effort and time to figure it out once it will save time and effort many times in the future, and make one a better engineer. In most cases, true impact force is a function of time during the impact event and almost impossible to calculate theoretically. Impact energy is much easier to quantify.

 

[mfgenggear]

,@compositepro
Thank you for the explanation
Much respect a star for you

 

[mfgenggear]

I am stubborn. It does seem simple.
But nothing is as it looks.
Time to move on

 

[LittleInch]

Well as the OP appears not to have even bothered logging in to look at the replies since he posted the question it all seems a bit moot. But I'll remember this one if it comes up again.



Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[hydtools]

Almost the same discussion 8 years ago.

Ted

 

[3DDave]

https://imgur.com/gallery/dLEtZ4Y

should demonstrate the variability due to boundary conditions for impact calculations.