School me on Load Capacity

[PMAC]

We have a new air compressor that weighs 815lbs and the footprint is 6.5ft x 2ft. The placement of choice is on the roof of a grinding booth that has a load capacity of 45lb/sf. What type of calculation do I need to do to determine if this is an approved placement? What advice can you give me? What should I be asking?

 

[Showkey]

815 pounds over 13 sqft is about 70 lbs/sqft. So the simple math answer is no by a very large margin.

Not accounting to the point load which not likely what the 45 pound limit is addressing. The grinding booth is not designed to carry a heavy load.


Link to understanding loads:

https://bct.eco.umass.edu/publications/articles/understanding-loads-and-using-span-tables/

 

[Dustball]

Also the compressor is most likely going to be unevenly balanced so you can't simply divide the load placed on the feet evenly.

Can you install channel iron to distribute the load to the corners of the booth?

 

[nadogail]

IMHO, this idea should go back to the drawing board.

 

[matt_i]

I wold use ERW box tube (electric resistance welded) or an I-beam.

Channel deflects in a twist with flanges-horizontal and very floppy in the I-yy direction with flanges-vertical.

You can work around that by going back-to-back and forming essentially an I-beam or going very heavy to work flanges-vertical but that's more steelwork than doing it with tube or I-

Something like an S4 x 7.7#/ft would be good for your load without doing any calculations.

If you did go back-to-back with channels welded to spacer tabs then there's the nice feature of having an instant slot to drop the threaded rods thru, with which you will secure the feet.

It deserves plenty of attention due to the risk factors of: overhead load and the guaranteed vibration and the propensity for people to be working underneath.

Strong gussets to legs all around, 7018 stick welding clean metal, torque prevailing (deformed-thread) locknuts, and bolt the legs to the concrete.

 

[Joemctag]

Grinding booth? You’re a fab shop?

 

[rburke65]

6.5 x2.5= 16.26 into 816 is almost 50 #.....ya need a better built roof

 

[PMAC]

Yep, I work in a fab shop. We are now building a platform to bolt it to before it goes up above the booth to distribute the weight more. Thanks all for the info.

 

[whateg01]

Yep, I work in a fab shop. We are now building a platform to bolt it to before it goes up above the booth to distribute the weight more. Thanks all for the info.

You don't just need to distribute the load more. Depending on the structure of the walls you may need more vertical support too