Cranes are different from other pieces of construction equipment because at their most basic function, they do not require other machinery or power to function. The bulldozer, excavator or tractor required some form of power – whether it be steam or gas, or oil. Many modern construction equipment dates back to some time in the 1900s. A crane is a machine that is used to lift and move heavy loads, machines, materials, and goods for a variety of purposes. They are used in all different sectors of industry, from construction to manufacturing to shipbuilding and material loading. Cranes are common along skylines as they are necessary to build the skyscrapers we so often see in our cities today. And cranes can be debided into different types such as Overhead Crane, Gantry Crane& and Port Crane.
While there are many different types of cranes, there are a few basic components or Crane Accessories like Hoist and Trolley worth mentioning. The main parts that can be found on a crane are as follows.
The Boom The boom is the most recognizable part of a crane. The boom is a long arm that can either be telescopic or fixed. They take on a variety of roles depending on the type of crane and how it is built. They are able to work without jibs and are sometimes the main component on a crane. The primary purpose of the boom is to lift, move and position material. They bear the majority of the load and are responsible for determining the reach of the crane.
The Jib The jib crane is the lattice-type structure attached to the end of the boom. Using a lattice-type build helps to reduce the weight it adds to the front of the boom. It is fixed in length and cannot be extended or retracted like a boom can. Some versions of mobile cranes have a jib fixed to the end of the boom to help move and lift materials. The jib or jib arm has one main purpose: to help keep the material clear of the main support so that it doesn't hit it while being moved. That being said, jibs are not always required and are often looked at as extra pieces that can be used when needed.
The Rotex Gear
The Rotex gear is the mechanism below the cab of the crane. It allows the cab and boom to rotate left and right. A simple movement, but incredibly important for the function of the machine.
The name "counterweight" pretty much describes the purpose of them: to counter the weight on the front of the crane while lifting material to prevent tipping. They help add stability to the machine and generally increase stability. Many cranes have adjustable counterweights so that they fit the specific requirements of a load or job. On tower cranes, for example, the counterweight can be seen at the other end of the jib.
Outriggers Outriggers may be one of the most important factors for crane safety. The function of an outrigger is to supply additional support. The purpose of an outrigger is to distribute the load of the crane over a large enough area so that the crane itself doesn’t tip over or become unstable. All outriggers should either meet or exceed the weight requirements of a crane or job. Outriggers do not compensate for unstable land. OSHA requires cranes to be assembled on firm ground that is drained and graded sufficiently. Supporting outriggers are meant to be used in conjunction with proper ground standards and do not make up for unstable ground.
In order for cranes to actually lift and move material, they require some kind of line or rope to do the actual lifting. In the case of cranes, this material is a reinforced steel cable. Steel ropes were first used for mining hoists in the 1830s. The wires used today are highly reinforced, resistant to corrosion, absorb any movement or force, and have extremely high breaking points.
The Hook Finally, the crane must have some way for materials to be attached to it. The most typical way this is done is through a hook. The lifting hook on cranes is usually equipped with a safety latch to prevent the material from slipping off the hook in transit. Crane lifting hooks are often made of steel or wrought iron. Hooks for heavy-duty cranes and loads are usually heat-treated and forged in order to make the hook as strong as possible.
- Created: 13-01-22
- Last Login: 13-01-22