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ups.com...


Rick wrote:
On Mon, 27 Jun 2005 11:34:06 +0000 (UTC), "John"
wrote:

I live in Leeds where there is lots of redevelopment going on in the
city
centre. I was driving through the other day and got wondering "How do
they
build them and get the crane cab and boom up there?" Do they use
another
crane? If so how did they build that one, did they use another crane?
If
so....... Do we have a chicken and egg situation here? I have never
seen
one of these things erected, they just seem to appear overnight. Is it
the
crane fairies job to put them there?

Cheers

John


They build the top bit neer the ground, with another crane. The bottom
section of the upright has hydrolics, and jacks the whole lot up, a
new section is inserted, crane is now 20 foot higher. repeat untill
crane is desired height.

Rick

But once the development is finished, what happens if there is no clear
space to reverse the process? The jib must be detachable in some way?

They reverse the process. Room to do this is one of the things they take
into consideration before building it.

If they didn't do that, they'd find themselves in the same position as the
legendary biker who took all the components of his motorcycle upstairs to
his room where it was warmer to work. Built the bike and then had a little
trouble with the bend in the stairs. :-))

Steve