Tube Steel Load Capacity

[ztrabun]

I am looking to build a large barrel rack. The rack will be 12ft tall, 3ft deep, and 17ft wide. Each barrel is 40" wide and when full will weigh approximately 1500 lbs. I was thinking of using 3x3x.25" tube steel as the frame. Can someone tell me if the longitudinal length (17ft) will be strong enough to hold approximately 6000lbs of weight distributed evenly over the length of the rack. Crude picture attached

 

[Bondo]

Ayuh,.... My uneducated, non-engineer Guess is,....

3x3 ain't gonna cut it,....

3x6 maybe,...

 

[laser3kw]

here is a calculator
beam calculator link
using 2 hollow square horizontal members 3x3x.25 x 204 each carrying 3000lbs (1/2 of 6000 total), each beam will deflect 2.50 inch. Not good

 

[matt_i]

I would think something like a S6 x 12.5 I-beam (or better) used in triplicate is better. The 3x6 box tube with 6" dimension vertical is a close second, also used in triplicate.

Stick weld every joint, E7018 is my recommendation.

Across the 17' I would X-brace the beams in the plane of the top surface, or plate with steel (to be included in the weight). I would angle-brace (gusset-brace) the connections to the posts. Epoxy anchor to a concrete floor on foot-plates.

Seems like a simple structure but a lot of risk here.....

 

[bon3s]

We build things like this at work all the time, Id stay away from anything square and as the above have said go with I or H beam or with a rectangular tube as they are more rigid, additionally cross braces, gussets and the third rail should all be done no matter what u decide for materials.

Depending on your welding skills as well as what welder you have access to, this can very easily done with mig as well as stick.

 

[davewo]

Go to Home Depot and observe the pallet racks they use to hold tons of concrete.

 

[red92s]

Go to Home Depot and observe the pallet racks they use to hold tons of concrete.

Pallet racks don't span nearly 17' (probably more like 10'). It's the really wide span without a support that's killing him, not the heavy load.

 

[jimgood]

What if diagonal braces were added? Does the space underneath need to be clear?

 

[BLUE72CAMARO]

Yeah 17' span with no center support is going to take something pretty stout.

 

[bigguns69]

You can see my calculations and the beam table from machinery handbook. The 3x3x1/4 wall tube calculates right out to the yield strength of general structural steel, A36, 36,000 psi. Need to shorten the unsupported length and or add more beams if you want to use this material. You could use: 4x4x.25" wall would give you a Safety Factor of 2, 3x6x.25" gets you a SF of 1.85, 6x8.2lb. channel will get above SF of 2. You want a section modulus, Z in the x direction of 4.2 in^3 to get a SF of 2. Then you are good. I would gusset the beam, more for the legs, given the height.

 

[jimgood]

Hmm...now I'm suspicious. First time poster. 1 post. No response after all this advice? Either a troll or seriously rude.

 

[DougWil]

Hmm...now I'm suspicious. First time poster. 1 post. No response after all this advice? Either a troll or seriously rude.

Probably found out how much new steel costs.

 

[tapered-pin]

Hmm...now I'm suspicious. First time poster. 1 post. No response after all this advice? Either a troll or seriously rude.

lol, you won't have to worry about that from me..
(hi, y'all)


I've found that most people just want you to tell them their plan will work, regardless of how insanely under-engineered it is..