Monday, October 8, 2007

RE: Choice between intermittent and continuous fillet weld in Crane girder ( I beam with channel top)

What is required by analysis?  What size crane and what is the service classification?

 

For light to medium cranes with moderate service we typically design the “W” for the vertical load and the “C” for lateral loads.  An intermittent weld is acceptable.  Even if you considered it as a composite section, continuous weld is probably not required.  The most important consideration is to consider the deflection.

 

However, Tips to Avoiding Crane Runway Problems by David Ricker (AISC Engineering Journal 4th Quarter 1982) recommends continuous due to fatigue.  He recommends vertical deflection of L/1000 to L/1200 for heavy cranes and horizontal deflection of L/400.

 

Gary W. Loomis, P.E., Senior Structural Engineering

Master Engineers and Designers, Inc.

-----Original Message-----
From: Sanjay Verma [mailto:sverma@p-and-i.com]
Sent
: Monday, October 08, 2007 1:16 PM
To:
seaint@seaint.org
Subject: Choice between intermittent and continuous fillet weld in Crane girder ( I beam with channel top)

 

Fabricator is insisting in providing intermittent fillet weld in Crane girder (I-beam with channel top).

 

I have seen continuous weld not a problem contrary to fabricator who is  advocating that continuous weld will leave warped channel surface.

 

Please advice / share your experience.

 

 

Channel web thickness is  .4 inch and recommended continuous weld is ¼.

 

Best Regards,

Sanjay Kumar Verma,  P.E.

818-7203140