Hoist Beam Design

[SKJ25POL]

Have a 21 ft span, a 1 Ton capacity and is outdoor, supported at each end.
I looked at CMAA 74 but need a more simpler lamgauge or an example.
Any help (sample calc or reference) will be appreciuated.
It has to be an "S" shape

Thanks
Babak

 

[SJBombero]

Assuming this is for a monorail system, you will need to check deflection 3.5.5, flange buckling 3.5.6 (usually governs), and the local flange stresses 3.3.2.6 caused by the trolley wheels. The loads/stresses would have to be combined using CMAA load combinations. Wind (weak-axis) bending could be a concern since it is outdoor.

 

[boo1]

Integrity Crane has an example design of a monorail system

http://www.integritycrane.com/downloads.htm

 

[steele6707]

An applicable code reference (US and possibly more?) would be ASME NUM-1 which I believe replaces the CMAA document. The current version is 2009. The document is titled "Rules for Construction of Cranes, Monorails, and Hoists (With Bridge or Trolley or Hoist of the Underhung Type). I saw online the price was $195 and it is 156 pages. I only have a very small portion of the 2000 version, so I can't comment on the document.

 

[SJBombero]

CMAA hasn't been replaced yet. The latest edition is from 2010. The latest ASME NUM-1 is from 2009. I can't comment on the content of ASME NUM-1 without reading it, but many of the other crane related specs from ASME and ANSI are have little real design content. A really good crane design spec with examples is AISE Tech Report #6, but unfortunately that is not for monorails.

 

[WiSEiwish]

Cranes should be tested and ASME B30.11 lists the proof test requirement of 125% of the rated load.
AISC 7 has formulas for the longitudinal and lateral loading for the hoist.

 

[boo1]

ASME B30.11 looks like it is construction, installation, operation, inspection, testing,
and maintenance of under hung crane and monorail systems.

per ASME B30.11-2010
"11-2.2.2 (d) If a load test is conducted, the load shall be not less than 100% of the rated load of the crane or monorail
system or more than 125% of the rated load, unless otherwise recommended by the manufacturer or a qualified person."

 

[Brad805]

1 ton, 21'-0" span. Seems straight forward. Life is too short.

 

[ColinPearson]

MH27.1 2009 is interesting. It's NOT for rolled shapes so it doesn't directly apply, but it does have some good bits in it.
boo1 is correct that B30.11 is not a design document.

You may want to look at this sheet for a quick check but I'd encourage you to do your own homework as well.

 

[ajc2014]

AISC DG7 has an example I believe and ASCE-7 has a pretty good description of the required loadings and serviceability. Then check the items listed above. I do not suspect that FLB will control on small loads on an S-shape... Also make sure to design for fatigue if it applies.