LUFFING TOWER CRANE
This crane does not have a trolley, the hoist rope always comes out of the top jib section. These cranes usually operate in single fall or two fall on the cable. In single fall the hoist is extremly fast when compared to the other types of cranes which must operate in two fall at a minimum. Due to the design, weight is transfered from the cranes jib much more effectivly than the other types of cranes, resulting in higher lifting capacity. For those wishing for a practical example just try holding a heavy weight vertically, as a luffing crane does, then try holding horizontally like a hammerhead tower crane.
These cranes dominate cities where hammerhead tower cranes cannot operate due to surrounding structures in their radius which the luffing crane can avoid. They are also often found on multi crane sites, again due to being able to take up a much smaller radius
The market leader for this type of crane has traditionally been Favco, however in recent times we are seeing quite a lot of luffing cranes from Jaso and Comedil working in Sydney
A-FRAME TOWER CRANE
Outside of the central business districts these are probably the most common crane you will see around. The a frame extends above the cranes jib and has a pendant that runs from the top of the a frame to the jib and counter jib
FLAT TOP TOWER CRANE
Flat top tower cranes are good for multi crane worksites or for sites where height restrictions apply such as airport flight paths, the lack of an a frame means higher cranes can slew over the jib without hitting the a frame. On these cranes the jib has to be larger to get the strenght required to not require the a frame.
SELF ERECTING TOWER CRANE
You could call this crane a hybrid of a mobile crane and tower crane. It has outriggers just like a mobile crane but unlike the mobile crane it cannot transport itself. Set up of these cranes is much simpler than other tower cranes as the whole crane is lifted into place, outriggers set up and counter weights put on. From there the crane sets itself up by unfolding using its own hoist motor
PORTAL TOWER CRANE
This is a tower crane that has been set up to travel along tracks or rails, similar to the tracks a train travels on. This type of setup is not very common and is usually used on long term / permanant ongoing projects such as shipyards or factories. In Sydney the Navy base Garden Island has threefavco portal tower cranes. Note the large portal frame at the base of the crane.
REMOTE CONTROL CRANE
Many cranes can be set up for operation in remote control. Some cranes will be set up for both cabin control and remote whilst others will be exclusivly one or the other. Smaller cranes deflect quite a lot so my personal belief is if it is below 10 tonnes go remote and above its easier to operate from cabin. There are advantages and disadvantages for remote control use. Main disadvantages are- remote will cut out from interference from similar frequencies eg, garage remotes, remote batteries need to be changed over when flat, harder to see things when operating from remote - cabin generally better view, remote may become faulty and cause downtime. It is not just small cranes that can be operated from remote, I have seen 12 tonne Jaso cranes set up with remote as well as 20 tonne Comedil cranes.
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