On the Eurpean continent, especially in Germany building sites
exclusively employ cranes that have a horizontal load arm where the
load distance from the cran is regulated by a horozentally travelling
hook. In Australia, and in Asia, ( I don't know about North and South
Ameria, nor Africa), most cranes used in the construction industry are
Jibcrane where the load distance from the crane is regulated by
raisinfg and lowering the load arm,(jib) Which crane type is better
and why is not the better type used universaly?

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Request for Question Clarification by alienintelligence-ga on 07 Sep 2002 18:32 PDT

Hi hermann...

I might be completely backwards here... but I
believe the Jib Crane is the one you described
initially.

"Jib Crane" at dictionary.com
[ http://www.dictionary.com/search?q=jib%20crane ]
Jib crane (Mach.), a crane having a horizontal jib on which a trolley
moves, bearing the load


Are we comparing this type of crane (Jib Crane)
[ http://dalesorenson.com/digital_photography/2000_berlin/cranes.jpg ]

with this type of crane

[ http://www.bigdig.com/artist/oconnor/cranes.jpg ]

thanks,
-AI

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Clarification of Question by hermann-ga on 07 Sep 2002 19:42 PDT

We are comparing crane as in link ...dalesorenson.com with cranes as
in ...bigdig.com. I call the latter crane a jib crane due to the
triangular outline formed by the boom - rope with hook and load -
horizontal ground plane. There is also a trianguler, (jib) outline
formed by the vertical tower (mast) the boom and the rope from the top
of the tower to the tip (Clew) of the boom.

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Request for Question Clarification by alienintelligence-ga on 08 Sep 2002 00:47 PDT

I see what you mean and I think
that cleared a point I was missing
in my searches.

I tried finding at the very least,
a compendium of cranes. None. Or
terms associated with cranes, not
many links out there.

The few pages I found referring to
Jib Cranes were of the dalesorenson.com
pictured ones. But when looking up
the boom type, I saw jib associated
with it. The jib is the part after the 
perpendicular member on the boom
in that case?

Is it possible the main difference is:
The inverted L "Jib Crane" has a majority
of it's mass balanced on an upright
structure and it is more suited to
being a fixed emplacement? Because it
would not take the change in inertia
from lateral movement as well as the:
Boom/Jib type of crane which has the
majority of its weight supported near
its base.

I guess the moveable boom/jib crane
would be preferred to use in an area
that has a lot of movement area. A
good ground surface to move on. 

Whereas here in the LA area, you could
not seal up a street just for a crane, 
so you quickly erect a structure, then
affix the crane to the central topmost
point.

Also another point could be the lateral reach
of a Jib Crane can be greatly exaggerated
without a great expanse for crane movement.
Centrally located, the Jib Crane's greatest
reach then becomes a radius that doubles
the area accessible to the crane.

Lastly, a good point. I haven't seen boom/jib
cranes the height of skyscraper. ;-)

I would think then neither is better,
both are suited to moving large, bulky
and/or heavy items from point A to point
B and at different heights. They both
have their own rightful place. One better
for vertical/fixed area load manipulations,
where the vertical ascent would be a
possible concern, such as the jib crane. 

While the other type of crane, the boom/jib 
type is better suited for an open area of 
construction that doesn't have to exceed a 
maximum boom + jib height.

This is posted as a r/f/q/c because
it might not be the concepts you are
seeking.

-AI

There are no standard terms for crane components. Each region of the
world name each part of the crane differently...even the
manufacturers.

The "T" type tower cranes are popular in Europe, and the "Luffing"
(raising or lowering boom to change lift radius) tower cranes are more
popular in the USA and Asia. "T" tower cranes typically have a lower
capacity, but longer "Reach". Luffing boom tower cranes are higher
capacity but shorter reach.
Luffing tower cranes are also more popular where many cranes will be
operating together on one project (less chance of collisions between
booms) and for example in New York city where it is not permitted to
swing a crane over a building adjacent to the one you are working on.