For every large construction projects, tower cranes are always used. Tower cranes are obviously designed to lift up the construction stuffs specially those heavy ones. Tower cranes can be used to transport objects from rise hundreds of feet in the air and can reach out just as far. Powerful tower cranes can rise up to 150 feet and can lift up to 19 tons. It can lift a wide variety of building materials like steel, concrete, and even big generators.
Tower cranes would not be able to do that kind of work without its important components. The most important part of the crane is its steel components because the tower crane uses this part of the machine to lift very heavy objects, it requires great strength.
Crane manufacturers use a variety of substances known as HSLA or High-Strength Low-Alloy steels. One of the basic parts of the Tower crane is the base which is bolted to a large concrete pad that supports the crane and connects to the mast or tower which gives the tower crane its height. The gear and motor that allows the Tower crane to rotate is the slewing unit which is attached to the top of the mast. The portion of the Crane that carries the load is the jib or working arm. The operators cab is the most important because it is like the brain of the Tower crane. With all these components working together, a tower crane would be fully functional and be used to lift heavy objects.
Though all of us have seen Tower Cranes before, few of us know their real capabilities and how much they can actually lift. The maximum load of that a usual Tower Crane can lift is 18 metric tons or equivalent of 39,690 pounds of weight. But if the load is positioned at the end of the jib or the working arm, the Tower Crane cannot lift that much weight because the closer the load is positioned to the mast or the tower, the more weight the Tower Crane can lift safely.
The Tower Crane has a specifications when it comes to maximum unsupported height which is 265 feet or equivalent to 80 meters, maximum reach which is 230 feet or 70 meters, maximum lifting power which is 19.8 tons and counterweights of 20 tons. The Tower Crane also uses two limit switches to make sure that the operator does not overload the Crane. These are the maximum load switch and the load moment switch. The maximum load switch monitors the pull on the cable and make sure that the load does not exceed 18 tonnes, while the load moment switch makes sure that the operator does not exceed the tonne-meter rating of the tower crane as the load moves out on the jib. That is why it is very critical to operate this massive machine. The Tower Crane operator has to be very skilled at what they does because there is a lot to risk when you are swinging 18 metric tons of load hundreds of feet above the ground.
Safety is the most important factor to be considered during a construction. The Tower crane seems quite unsafe to the naked eye because they have no support wires of any kind. But the Tower Cranes stability depends on certain elements. The first element is a large concrete pad that the construction company pours several weeks before the crane arrives. The concrete pad typically measures 30 feet by 30 feet by 4 feet and weighs 400,000 pounds or 182,000 kilogram. The Tower Cranes are essentially bolted to the ground to ensure their stability. Large anchor bolts are embedded deep into the pad support in the base of the Crane. But before that, Tower Cranes are delivered at the construction site on 10-20 tractor trailer rigs.
Mobile Crane is used to assemble the jib and the machinery section. The Mobile Crane then adds the counterweights. To rise to its maximum height, the Tower Crane grows itself one mast at a time. Special devices within the Tower Crane prevent the user from attempting to lift a weight heavier than allowed. Because the United States Government sets specific regulation through safety that limit the weight that a specific Crane is allowed to lift. A completed Crane is first tested without a weight to ensure that all of its components operate properly. It is then tested with a weight to ensure that the crane is able to lift heavy objects without loosing stability. Safety is ultimately depends on that proper use of the Crane.
