Calculating Capacity of Steel Rack: Yield Stress Issues

[RJCanz]

TL;DR Summary

Load capacity on Racks with steel pipes as load carrier

Hi guys. Recently I've been assigned to know / calculate the capacity of the racks in our section. Our racks has layered steel pipes that are carrying the loads. After actual testing it can carry a load around 25 tons after yielding or having a bend. So my next step was to calculate for its yield stress so I can calculated an allowable stress and an allowable load with a factor of safety right after. However, after calculating it's stress in which I used force over area (A = 3 sq.m.) I calculated a stress which only results to a kilopascal value while I have searched yield stresses of some materias are mostly in megapascals(MPa) is there wrong with my calculations? If there is, can you help me. Thank you!

 

[berkeman]

Welcome to the PF.

Summary:: Load capacity on Racks with steel pipes as load carrier

Recently I've been assigned to know / calculate the capacity of the racks in our section. Our racks has layered steel pipes that are carrying the loads. After actual testing it can carry a load around 25 tons after yielding or having a bend.

That's a pretty heavy load! What is the application? If the racks fail, where does the load fall?

And why have you been assigned this calculation if you have to ask for help on the Internet? Seems strange to me...

 

[RJCanz]

Welcome to the PF.

That's a pretty heavy load! What is the application? If the racks fail, where does the load fall?

And why have you been assigned this calculation if you have to ask for help on the Internet? Seems strange to me...

Apparently our boss doesn't know its capacity in tons so he assigned me to do it. Our section is overhauling of gearboxes, pulleys etc. And after these are fixed it is stacked in those racks. Our racks has 2-3 layers and the 25tons I have said was the capacity only of 1 layer. But I wondered when I computed for the stress with that known weight it is only in kilopascals so I wonder if it's wrong bc I have seen mostly stress capacities are is mega pascals

 

[berkeman]

I'm guessing that you are not based in the US, because (hopefully) we would require professional engineer certification to be doing calculations like this. I will temporarily lock this thread to ask the other Mentors whether we should allow your thread to go forward...

UPDATE -- The thread will remain closed. Please seek the help of a professional engineer and have your insurance company sign off on the final design. Thanks.