It is as you enter from Luton that you first glimpse the crane towering above the trees, but it is hard to grasp why it is necessary for such a tall crane. As you come closer the reason becomes apparent, the site is long and thin and to deliver concrete to where it is needed and avoid the concrete mixers from unnecessarily interfering with local traffic these mixer vehicles approach down a tiny alleyway to the edge of the site then feed a hopper which is then hoisted and swung to where it is needed. A lower crane cannot move in these confined spaces, but a taller one can because the angle of the arm is so steep.
The hopper has an elephant’s trunk to pour the concrete where it is needed, and an ingenious tilting skid allowing it to be filled directly in manageable doses directly from the mixer lorry. The mixer is therefore present for the entire time it takes for the hopper to be filled and emptied until the nixer’s entire content is exhausted, so it is a three-man operation: the driver, a signaller to let him know when to pour and when to stop whilst the third man folds the trunk and tips the hopper and swivels the chute. To minimise the amount of concrete spilt on site, there is a skip at the side to deal with the dregs after each delivery to the hopper.
I have tried to capture the elements of the process and to convey just how tall this crane is and what a splendid piece of kit it is with its smart cab, all its cables and counterbalances, and how the operator has a bird’s eye view of both ends of the hopper’s travel from mixer to where it is being poured over the mesh of steel reinforcing cages. It is a non-stop process, except for when the mixer has to drive out when its load is finally exhausted, and another has to take its place.
Work – I could stay and watch it all day! Well, photograph it!
If a tall structure is being built at the construction site, then a tower crane is absolutely necessary. This are generally fixed to the foundation, but at times this can also be attached to the side of the structure for ease of use. You will get the extra advantage of lifting weights to or from extremely high places when you have the crane to do the heavy lifting. Its working mechanism includes a central mast, and attached to it is the slewing unit of the machine that acts as the motor of the unit. The slewing unit of the machine helps the arm part of the crane in moving objects by moving throughout a 360 degree range, and lifting objects from one place and putting it down in another.
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