crane rail runway beam splice

[taz004]

I am detailing a splice for a w 21X62 crane runway beam. Is it possible to use a welded plate splice. The top and bottom flange will be fully welded and a 10" x 18" x 1/4" plate will be continuously fillet welded on each side. I am trying to stay away from using any bolts. Any info would be appreciated.

 

[kslee1000]

Where on the span the splice is to locate? Two side, or one side plated?

 

[taz004]

plate on each side. 30'-8" span. I want the splice to be sufficient anywhere on the span so i want to design it for the worst case scenario.

 

[kslee1000]

I would avoid splicing runway girders. 30'-8" is not a long span, why not just make the girder simply supported. Moving load, vibration and fatigue concerns will make splice design extremely difficult with very high uncertainties. If girder deepth is the concern, you might consider build-up shape to solve both strength and service problems.

 

[MikeMet]

Be sure you know what your are welding. Run a carbon equivalent calculation on the parts to be welded. Make sure they are truly weldable. If not bolt the splice. If it is, make sure you have a qualified weld procedure for that material that will prevent cracking. Cracking of any type could lead to fatigue failure in the future.

 

[hokie66]

Why are you trying to splice crane girders? To save money on the steel purchase? If so, that is false economy. Crane girders, except for light duty cranes, should be simple spans.

 

[dik]

I would stay away from a welded splice for anything but a Class C type crane. There are numerous publications that recommend against welding crane runway beams, including the AISC, if memory serves.

Dik

 

[garpe]

Simple spans is the way to go. There is a good article in the AISC technical publication about this very thing. It's at my office so I can't give you anything specific. Do a search at the AISC website. The splice may become a fatigue issue so I would certainly check it for that. AISC Manual of Steel Construction.

Greg Robinson

 

[Gymmeh]

taz,

you may want to get your hands on the cmaa 70 or 74 guide (if my memory serves me), it shows you everything you need to know about bridge cranes.

http://www.techstreet.com/cgi-bin/results

I think this is the Canadian equivalent.

http://www.cisc-icca.ca/publications/technical/design/craneguide/

Its been awhile since I have design cranes but I don't ever remember design welded connections for the rails of anything lifting over 500lbs.

The times I have seen weld connections were on under hung light rail, basically the small stuff for work station or monorails (which I assume doesn't fit your case with that w21@62).

best regards