Tool ignorance - impact & compressor

[ondarvr]

Re: Tool ignorance - impact & compressor

I have a couple compressors, a large industrial one that max's out at 100PSI and a very small cheap one that max's out at 125PSI.

For very stubborn bolts I need to use the small cheap one, PSI trumps CFM for this purpose.

I've also had impact wrenches that sucked, I gave those away and only kept the good ones.

 

[bigdee]

Re: Tool ignorance - impact & compressor

I have a couple compressors, a large industrial one that max's out at 100PSI and a very small cheap one that max's out at 125PSI.

For very stubborn bolts I need to use the small cheap one, PSI trumps CFM for this purpose.

I've also had impact wrenches that sucked, I gave those away and only kept the good ones.

Funny you mentioned that b/c when my impact wrench stalls I have switched to my little 3 gallon pancake compressor! Now I use my electric one most of the time for tough jobs....never ran out of electrons on that one!

 

[WIMUSKY]

Re: Tool ignorance - impact & compressor

I've also had impact wrenches that sucked, I gave those away and only kept the good ones.

I got a free one, plus other air tools when I bought my 60 gal C/H. That thing was worthless on lug nuts. Torque makes a big difference on how the wrench will perform. I believe it was only 200ft/lbs....... I bought a new one, Klutch, that works fine......

 

[ondarvr]

Re: Tool ignorance - impact & compressor

I need to get an electric one, I've used them, just never owned one.

 

[dingbat]

Re: Tool ignorance - impact & compressor

deleted...I give up! :facepalm:

How about this. I will run my impact wrench for 5 seconds and show you the video of the pressure of the tank before and after!!!!! The compressor will be turned off.

Now I am very curious. Do you actually own an impact wrench?

The embarrassing part is I designed industrial pneumatic and hydraulic drive systems for 15 years.:facepalm: And yes, I have a variety of air tools.

The 63 psi sounded a little funny to me as well...but the math supports it, or so I thought.

Ingersoll-Rand 231C - 1/2" Drive Super Duty Air Impact Wrench

I confirmed your units usage while under load is 22 cfm @ 90 PSi = 22 CFM/60 sec. = 0.366 cf/sec. x 5 sec. = 1.83 cubic feet.

At issue..... the volume of a 20 gallon tank of compressed air. Gallons conversation doesn't work with compressed air. We both made that error.

A 20 gallon tank contains 25 cubic feet at 125 psi, 21 cubic feet at 100 psi, etc. The first three bursts @ 90 psi would be "buffered" by the over pressure in the tank. First blast would drop the pressure to ~116, second to ~100, the third to equilibrium at ~90 psi. Each subsequent burst would drop the pressure ~10 psi.

 

[bruceb58]

Re: Tool ignorance - impact & compressor

So...does that put to bed that the CFM of the compressor doesn't matter to the OP in testing his wrench since he has 20 gallons at 110PSI?

 

[bigdee]

Re: Tool ignorance - impact & compressor

The embarrassing part is I designed industrial pneumatic and hydraulic drive systems for 15 years.:facepalm: And yes, I have a variety of air tools.

The 63 psi sounded a little funny to me as well...but the math supports it, or so I thought.

Ingersoll-Rand 231C - 1/2" Drive Super Duty Air Impact Wrench

I confirmed your units usage while under load is 22 cfm @ 90 PSi = 22 CFM/60 sec. = 0.366 cf/sec. x 5 sec. = 1.83 cubic feet.

At issue..... the volume of a 20 gallon tank of compressed air. Gallons conversation doesn't work with compressed air. We both made that error.

A 20 gallon tank contains 25 cubic feet at 125 psi, 21 cubic feet at 100 psi, etc. The first three bursts @ 90 psi would be "buffered" by the over pressure in the tank. First blast would drop the pressure to ~116, second to ~100, the third to equilibrium at ~90 psi. Each subsequent burst would drop the pressure ~10 psi.

There is nothing to be embarrassed about Dingbat. We have all been there once or twice or many more. It was a fun and interesting debate. This forum is all about sharing ideas and your input is appreciated.

 

[Tim Frank]

Re: Tool ignorance - impact & compressor

At issue..... the volume of a 20 gallon tank of compressed air. Gallons conversation doesn't work with compressed air. We both made that error.

Sure it does.
Your error is trying to relate Boyle's Law to any of this. You need to use the general Gas law, PV=nRT

A 20 gallon tank contains 25 cubic feet at 125 psi, 21 cubic feet at 100 psi, etc.

A 20 gallon tank holds 2.7 cu.ft.....period...air, water, maple syrup...pressure does not matter at all. If you are talking about the mass of air....different story.

 

[coolbri70]

Re: Tool ignorance - impact & compressor

or it doesn't matter how it blows if your tools broken:faint2:

 

[bigdee]

Re: Tool ignorance - impact & compressor

or it doesn't matter how it blows if your tools broken:faint2:

Hey, that ain't too funny to an old guy like me.......