Transporting and transferring heavyweight material has a crucial relevance to the construction industry. Many innovative developments have been made to answer this problem of moving larger building materials, one of which is the crane truck. This is a lifting device that is mounted on a truck chassis. Anyone who is associated with the construction industry will more than likely have a lot to say about the significance of these tall pieces of machinery in shifting heavy objects from one location to another during the building process. Construction sites and factories are using this enormous machine because of its capacity to lift and transport heavy objects.
With the rapid development of today’s construction industry, the crane truck has so many advantages in terms of lifting, shifting and lowering large and heavy objects, especially in the fabrication of tall buildings. Various types of these machines are put into service such as tower, truck-mounted, mobile, and telescopic ones. All of these use the same principle of counterbalance to make sure that the equipment will maintain its stability while hoisting heavy objects in a horizontal direction.
Theory of Conservation of Energy
To understand the function of construction cranes, their mechanisms and the technical aspect involved in the operation of the lifting equipment, one must understand the theory of the conservation of energy and the principle of counterbalance. The theory of the conservation of energy stipulates that the energy needed in lifting an object should not go beyond the energy needed to carry that same object. This can be seen by examining the normal position of any type of this machinery.
Principle of Counterbalance
On the other hand, the principle of counterbalance explains that a suitable weight should be utilized to counter the working jib, which is commonly located directly across from the crane tower. The counter jib and working jib are placed opposite of each other. Though the conceptual whole is made up of complicated and related parts, and all of its component elements are essential in the operation of a correctly-functioning machine, this principle is only applicable to tower versions of this equipment.
All types of this machine use mechanical arms or levers in lifting large amounts of heavy material. Along with the swinging arm (boom support) are ropes, chains and pulleys, all of which are necessary to raise comparatively great physical weight. The structure has a truck chassis and a boom support assembly, which is mounted and can pivot on a parallel vertical platform.
The present mechanism is to utilize a pantograph linkage mechanism wherein the swinging arm is pivotally mounted to a platform base. According to the design, the operator can handle the machine effectively because of the hydraulic apparatus responsible for the motion of the swinging arm.
Levers, Pulleys and Hydraulic Cylinders
To know and comprehend the meaning of the mechanical principle and underlying use of construction cranes is to remember three simple devices that produce mechanical advantage: levers, pulleys and hydraulic cylinders. Based on the principle of the lever, the ratio of the lifted object is equal to the ratio of the length of the longer arm and the shorter arm. To simplify this, the beam balance is created around the fulcrum, wherein the weight of the longer arm is equal to the weight of the shorter arm. The distance from the fulcrum to where the energy is applied is proportional to the distance from the fulcrum to where the resistance has occurred.
On the other hand, the pulley system provides a mechanism that doubles the force applied to the weight being lifted. The force is multiplied by the number of lengths of cable passing between two pulley blocks thus creating a force that helps in lifting heavy objects. The hydraulic cylinder also helps in the generation, control and transmission of power to move certain heavy objects.
For several decades, a great deal of advancement has been made that goes through certain standards for exceptional performance. The National Crane truck for example, which is manufactured by Manitowoc, is known for having a high standard of durability and dependability for truck-mounted hydraulic machines. They have newly added features which are suited for almost every construction site need and are able to perform the job accordingly and efficiently.
In today’s construction businesses, crane trucks have been used in different ranges of the lifting process. Seemingly, all of these various types including National Crane trucks are functioning under the principle of mechanical advantage. We cannot deny the fact that the crane truck has contributed to the furtherance of the construction businesses.