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Re: Crane Design; SE v. ME

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Drew Norman wrote: 
 
>My office has designed a building to support a thirty ton bridge crane. 
The 
hoist runs along a bridge spanning 54' between trolleys which in turn run on 
rails spanning 27' between supports points where they are hung from our roof 
structure.  Reactions at these suspension points were provided to us by the 
crane supplier. < 
 
Please clarify - are the crane runway beams, which are fixed and support the 
crane rail, designed by your office or the crane manufacturer?  In my
opinion, 
the fixed crane runway is definitely a "structural" item and must be
designed 
to resist lateral seismic forces and transmit them to the adjoining
structure. 
 
>We have asserted that the bridge crane and its rails, which are to be 
designed by their supplier, are a substantial structure.  Our documents call 
for the design to be submitted to us (for verification of consistency with
our 
design of the supporting structure) under the seal and signature of a
licensed 
SE.  We were recently advised that the crane supplier asserts that the crane 
is a machine, not a structure, and that an SE signature is not required
(they 
have an ME who proposes to sign the documents). < 
 
Again, please clarify - did your contract documents state that the design of 
"the crane" shall be sealed by an SE or just that design "structures" shall
be 
sealed by an SE?  If the contract documents clearly spell out the
requirements 
that the crane design be sealed by an SE, then there shouldn't be an
argument 
- do what the contract requires.  But if the contract documents are vague 
regarding the crane design relative to structure design, the manufacturer
has 
a valid argument - a crane is a moving piece of equipment and is not a 
"structure" per se.  You should have a right to require the seal of an SE
but 
only if this requirement is clearly spelled out in the contract documents.