How Do Cranes Work

They’re a ubiquitous sight anywhere major construction is taking place; chances are, you’ve watched cranes at work your whole life. But how, exactly, do they do what they do? What sorts of jobs are they best used for? What are the different types of cranes, anyway? How do crane operators learn their trade? Read on to discover the answers to these questions as we discuss just how cranes work.

Types of Cranes

Of course, not all cranes work exactly the same way because there are actually many different types of cranes, each with a slightly different mechanism for operation. Which crane is used in a job depends on the needs of the job itself, as well as the area where the job is being performed.

One of the most commonly seen varieties of cranes is the lattice boom crawler. The term “crawler” refers to the fact that the crane can move on a set of tracks, while the lattice boom itself refers to the crane’s lifting arm. These machines are highly mobile while maintaining the incredible lifting ability of the most powerful fixed cranes.

Fixed cranes do not move in the same way that crawlers do. You’ll often see them permanently attached to an area where a lot of heavy goods are moved, such as a boat dock. On many construction sites, you’ll frequently see tower cranes, which are built to move heavy items to the great heights that are required for constructing tall buildings.

Telescopic boom cranes are another example of a more maneuverable type of construction equipment. As their name suggests, their arms can extend until they are much longer, which helps to achieve maximum portability for this type of crane. These are often moved around on wheels instead of tracks, which usually means they cannot handle the same amount of weight as larger cranes. Even so, they’re capable of getting to jobsites that other cranes cannot.

Physics of Construction Equipment

A crane is, of course, a somewhat complex piece of technology. Even so, it does what it does by employing the physics principle of simple machines. Simple machines, which include levers, pulleys, and inclined planes, actually work by multiplying the force that is applied to an object. Specifically, a pulley creates what’s known as a mechanical advantage, doubling the force applied each time a cable moves through one of its wheels. This is how cranes are able to lift many, many tons of weight.

Of course, this leaves the question of just how cranes manage not to tip over when they are lifting loads that weigh incredible amounts. To avoid being toppled every time they attempt a job, cranes make use of counterbalances, meaning they must weigh a great deal themselves. The force between the object being lifted and the crane itself must be balanced at the proper fulcrum point. This will give the crane maximum stability as it does its job.

Technology at Work

Modern cranes make use of a great deal of advanced modern technology. However, they most often achieve their great strength the same way they have done for years: with hydraulics. Hydraulic technology makes use of pressurized fluids to get the job done. This works because of a principle of physics known as Pascal’s law: if pressure is applied to a fluid, that pressure is then able to act against objects nearby, once again multiplying the force that is applied. A hydraulic system makes use of a pump that pressurizes the liquid being used.

In the past, hydraulic systems used water as their pressurized fluid. While it certainly works just fine to get the job done, a mechanical system that’s full of water is also prone to rust and corrosion. For this reason, cranes and other construction equipment nowadays use specially designed, petroleum-based fluids to create their hydraulic pressure.

Modern cranes make use of a great deal of cutting-edge technology to make their work more efficient than ever. For example, many cranes today are outfitted with a computer known as a crane operator assist device. Much like the computer in a modern car can provide continuous technical readouts about the car’s functioning, up to and including how much air is in the tires, the computer in a crane can offer an incredible amount of data. They can tell the operator exactly how much a load weighs, the angle of the boom itself, and much more. They are also outfitted with safety features that can warn an operator if an accident is imminent.

Who Drives the Cranes?

Even with a great deal of advanced technology used in modern cranes, it’s still absolutely critical that the operators are highly trained to work with the equipment. Indeed, it may be more important than ever that a crane is operated by someone who really knows what they’re doing. That’s why most employers in the construction business hold their crane operators to very high standards as far as training and experience.

For these reasons, most crane operators learn their trade at a specialized school, such as West Coast Training. There is a lot for them to learn inside of a classroom, including how the controls of various machines work, the physics behind cranes, and how to remain safe on a busy jobsite. Equally important, however, is for prospective crane operators to gain real-world experience, practicing with their cranes.

Experience in the field is especially important because the job is never done in a vacuum. Cranes work in tandem with other technology, as well as with human workers who are helping to complete the job. A big part of a crane operator’s field experience will involve coordinating their work with other construction workers. Sometimes, they may even need to move a load into an area that the operator cannot see. In this case, a partner will communicate with them exactly what maneuvers to make. It’s amazing to witness skilled crane operators performing their job in this way!