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  #21  
Old 12-11-2008, 11:58 AM
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iceman (Mike)
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What an amazing shot.
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  #22  
Old 12-11-2008, 12:15 PM
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rastis95 (Scott)
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Im not good with heights and that just made me cringe
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  #23  
Old 12-11-2008, 01:24 PM
wraithe
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Bugger that, I thought they had plenty of land to build on...

I dont think I would be anywhere near them things, Dont even like going into Perth when I am up that way..
In fact I dont like the widow makers down here being too close to the house...
Trees 80 metres high are scary enough...
My height limit is 2 feet, firmly planted on Terra firma...
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  #24  
Old 12-11-2008, 01:38 PM
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Louwai (Bryan)
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One more snippet of info.
THe older tower cranes had opening windows right in front of the driver.
The wondow sill was just below knee level when the driver was sitting. So all he had to do was lean forward a little & he could see directly down in front right to the ground.
Also had to wear a seatbelt. The cranes do flop about a bit & sometimes quite violently. In yrs gone by drivers not wearing seatbelts have been flung out of the window.

Especially when climbing. The crane perched in flippers with a weight on the hook & the boom moving up & down. The ctr of gravity moves & the whole main deck will flop forward or backwards.

Bit like a sideshow ride really...........


The good tower drivers are amazing.
I've personally been in a man-box hanging on the hook, totally out of sight of the driver.
I tell him on the radio to put us down on the ground (several hundred feet below, & still totally out of sight of the driver).
He lowers the box very fast & without any further instruction from me, he slows & stops the decent approx 1m above the ground & puts us softly down in the exact same spot as where he picked us up from.
All totally out of sight & without being directed by the people in the box.
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  #25  
Old 13-11-2008, 12:21 AM
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MrB (Simon)
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Cool, do they have any sort of DRO's(digital read-outs) up there?
I mean for things like cable length, degrees of rotation, distance of cable from main column, etc, etc?
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  #26  
Old 14-11-2008, 05:09 PM
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Louwai (Bryan)
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Quote:
Originally Posted by MrB View Post
Cool, do they have any sort of DRO's(digital read-outs) up there?
I mean for things like cable length, degrees of rotation, distance of cable from main column, etc, etc?

On the new late (very late) model ones yes, but nothing at all on the old units. Like the old Favco's.

The old ones have an angle indicator on the boom. This is just a pointer with a weight on the bottom pointing to degrees on a semicircle plate.

The tower crane driver will always put the man-box in exactly the same place on the ground.
When he first picks it up he'll note the deck rotation angle & also the boom luffing angle to get the position. (both indicators similar to described above) When the box is on the hook (with the box still on the ground) the driver will turn around & look at the cable drum on the winch & count how many layers of cable have run off.

So when he's putting the box on the ground, he'll slew & luff until his 2 indicators are pointing to the correct angles & then while he's lowering the the box to the ground he'll turn around & look out the back window & watch the cable drum.
Many of the experienced drivers will still do it this way even in a new crane, because they don't trust the digital readouts......



This pic is a "Favco". easiest way to tell a Favco is the 2 hydraulic rams at the base of the boom. These are the luffing rams which push the boom up & down. Other types of cranes use a wire rope & pulley system to lift & lower the boom.
Also a Favco has the ops cabin right in the middle between the 2 rams under the boom butt. Look at the cranes in the original pic. They have no rams & the ops cabin is out to one side, not in the middle.
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Last edited by Louwai; 14-11-2008 at 05:31 PM.
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  #27  
Old 14-11-2008, 05:39 PM
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Louwai (Bryan)
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My question is;
How are they going to get the last crane down???

What usually happens with 2 cranes side by side is;
One crane is dismantled & lowered piece by piece to the ground by the other crane.
Then the last crane is "climbed down" to a point where another crane can reach it & then dismantle it.

BUT,
This process can not happen in this situation because even climbed down as low as it can, the last crane will still be far above any other cranes reach.


My guess is helicptor......
Dismantle piece by piece & lowered by chopper.



You can see in this pic the crane is lifting another tower section ready to climb higher.
Each tower section is 3m tall.
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  #28  
Old 14-11-2008, 05:49 PM
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you would not see me going up there
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