Usually fixed on the opposite end of the boom ( of the load line) sometimes the auxiliary hoist- also called a whip line, may be rigged with a counterweight to help counterbalance the crane- this is more common with Railroad yard Gantry Cranes- one goes up , the other down. The portative Counterweight somewhat resembles an anchor but has a flat bottom instead of flukes - some have a double hook on both sides- discouraging use as a lifting hook. The Hammerhead Crane is a splendid example of the Cantilever principle- as is also used in such famous bridge structures as the Pulaski Skyway and the Firth of Forth bridge in Scotland.
Gardner Crane's birth name is Edward Gardner Crane.
Robert Scott Crane's birth name is Robert Scott Crane.
Wattled Crane was created in 1789.
Demoiselle Crane was created in 1758.
Nicky Crane died in 1993.
Lifting weight of the Tower crane depend up on the specifications given.one should lift the given load approximately 18 tonns. Counterweight value is the main value.one can lift the value equal to counter weight value.
efficency of crane shovel families
carbon steel and some of it has to be heat treated there is only a select few of tower crane manufactures that has the stamps to build them
*many tonnes
Mega Movers - 2006 Tower Crane 1-10 was released on: USA: 13 June 2006
We could look at eccentric loading on a crane as the weight or load that is off the vertical axis of the crane. There are lots of different cranes, but let's dive in, bounce around a bit and speak in general terms. We'll start by taking a look at what a crane does and consider our options. A crane is designed to lift loads up, which is a simple but necessary start. Cranes generally have a boom extending out from the central axis of the crane. Now focus on this. The mass of the boom will be acted on by gravity and "pulled on" while it's sticking out. And the straighter it sticks out, the more the effect on the crane. That is, the more the mass of the boom will be acting to try to pull the crane over. And that's with no load. Let's do something crude but that might help. Pick up a broom near the end of the handle. Hold your arm straight out and hold the broom straight up in the air. You can feel the mass of the broom. Now lower the broom to where it is sticking straight out from your arm. There is a greater torque on your shoulder now because you're holding the broom straight out. Let's jump a bit now to look at a special type of crane. The tower crane, which is used in the construction of tall buildings, has a movable counterweight. That allows the operator to "balance" the effect of the load and the effect of the counterweight. They'll offset each other to pretty much eliminate any eccentric loading. Obviously the tower crane can't handle much of that without being ripped off the structure to which it is attached. Simple and effective. Think this through a moment before moving on. Got it? Good. On the "back" of a "regular" crane is a counterweight to offset the mass of the boom. Without the counterweight, the boom may tip the whole machine in the direction the boom is pointing. Recall that when we stick the boom out straighter, it tends to "torque" the crane off its vertical axis more. Why wouldn't it? The counterweight is doing its job. But there is no perfect match here between the mass in the counterweight and the boom. That's because as the boom is lowered or raised, the "effective mass" of the boom changes, even with no load on it. Now let's do a "pick" with the machine. A pick is a lifting operation. When we set up a crane, we generally have what are called outriggers to spot. These are "legs" that extend out from the crane and have a "foot" on them that is hydraulically shoved down on cribbing. These outriggers make the lifting platform more stable, and you can see why. The effective "footprint" of the machine is much greater with the outriggers set. We're ready to do a pick. When we hook up a load and lift it, the operator will be trying to keep the boom as "straight up in the air" as possible. This will minimize that "off-center loading" or eccentric loading. He's got the knowledge, skill and experience to use the machine in a way that will prevent eccentric loading from permitting a safe pick.
Construction canes are primarily used for lifting and moving heavy objects. Some of the types of construction cranes are the Sidelift crane, the Jib crane, the Gantry crane and the Tower crane.
The counterweight balances the load in the lift-shaft.
They usually have bucket and paper tower beside the seat. I know, it 's gross.
Hard hat help the worker not to get hurt by crane or any piece of iron
Yo mamma so fat. :D
A tower crane is tall and narrow. Because of this, a small amount of tilt could cause the whole structure to topple. The base of the crane is loaded with concrete, which gives it a lower centre of mass to prevent it from toppling.