Hey fellas, I need to know where I can find tensel strength of a 2ft. peice of 3"x 3/16" angle iron.
I am building 2 cradles to suspend a cylinder that will weigh just under 1000 pounds.
And I am thinking of using a 2ft peice and gusseting it with a peice of plate steel for the cradle. I just need to know if the angle will hold atleast 600 pounds or more or if I need to get some 1/4" angle for this.

Thanks,
Clint

 

Nope, I'd use 3/8" stuff, especially if there is any side-play ine the assembly. Angle is very weak in that application, but still stronger than two piece of flat stock welded together.

 

Well, we pulled this thing outof the crate and it couldnt weigh more than 200or300 pounds,
that means no more than 500 loaded.
We cut 2 peices and have one side across jackstands and the other with the engine hoist and some chain connected at the end. Also, I won't need to gusset anything cause the cylinder has feet built into it.

 

Assuming A36 steel with a yield strength of 36000 PSI, you have an allowable max tensile stress of 0.60 * 36000 or 21600 PSI.

A piece of "angle" might have a dimension of 3" x 3" with a thickness of 3/16 inch.
This is (3+3) * (3/16) = 1.125 sqaure inches. The max allowable pure tension load, assuming dead weight and no vibaration is 24300 pounds. This assumes no holes drilled into the angle.

But I don't think this is the figure you want. Instead, you want to know if it will support the weight of the cylinder in a beam bending application. A 3x3x3/16 steel angle has a moment of inertia of 0.961 in**4.

Assuming a 2 foot span and a point load of 1000 pounds in the center.

The formula for beam deflection for this loading condition is:

Delta Y = F * (L ** 3) / (48 * E * I)

or 1000 * (24 * 24 * 24) / (48 * 30000000 * .961) = 0.01 inch (at the midpoint)

L/360 for this span is 0.067 inch

The section can easily support your proposed load.

Because of its asymettry, angle is subject to lateral/torsional buckling, hence the comments about weakness and the importance of controlling side-sway. At heavier loads, it is important to provide bracing to prevent out-of-plane buckling.

If the cylinder is to be operating whilst on this cradle, rather than just static weight, then it is important to design in a significant safety margin.

 

Well, the saddles on the cylinder will be bolted to the angle then 2 1/2 holes drilled for 1/2" allthread to sespend it in an equipment room. I is static axcept for water and freon that moves throught it. We were mainly worried about the vibration of the earth as we want it to last atleast a 100 years.
It is alcually a chiller vesil for air conditioning an old church, the old one has to many leaks.

 

For that sort of application, I'd use 2" 3/16" wall square tube, with the holes reenforced.