Understanding The 3 C’s Of Overhead Cranes: Class, Capacity, And Caution

Running and operating a facility often requires the use of big machinery and tools to get tasks done. If you're dealing with heavy materials, a lot of lifting, moving, and manufacturing can be completed with an overhead bridge crane. These cranes come in multiple sizes and offer support for all types of products including vehicles, water crafts, and industrial machines. The planning stage of an overhead crane purchase is one of the most important aspects of your implementation. Before you make a final decision, it's important to focus on three factors: class, capacity, and caution. Use this guide to help you select the proper needs for your overhead crane.


Not all cranes are created equal. Every manufactured crane is assorted into different classes. Worldwide, these classes are organized through the FEM, which stands for Federal European De La Manutention. In the United States, one of the main classification resources is the CMAA, or known as the Crane Manufacturers Association of America. The workload of the crane is broken down into a number of different classes. By knowing how often you'll use the crane, you can properly select your class needs.

For example, one of the middle classes available for overhead cranes is known as Class C. This class means that your crane will be performing moderate service on a daily basis. This breaks down to around 7 lifts per hour. These lifts are also about 50% of the full capacity that the crane can hold. This is a great starting point for your purchase options. If you think that you will be needing more than at least 10 lifts per hour, then you should move up to a Class D or Class E classified crane. If the crane work is limited, then consider a Class B crane. If your operations are continuous and involve heavy production, then you will likely need a Class F crane. This type of crane is also known as a "Continuous Severe Service Crane."

The main differences between these crane classes is the power and performance of the motors. You do not want to spend thousands of dollars on a Class E crane when a Class C crane can complete the job at hand. It will become a waste of time and resources. Research your best estimates for crane use and if needed, move one class above just to be sure that the motor will operate sufficiently.


Directly correlated with the class is the capacity of the crane. A crane's listed capacity is often the maximum weight that it can handle at a given time. To ensure that there are no break downs or performance malfunctions, you always want to have some leeway on the capacity that you choose. For example, if the products or supplies that you are moving weigh around 4 tons on average, then you would rather purchase an overhead crane with a capacity of 8 tons rather than one with 5 tons. A 5 ton capacity pushes it close to limit and could add to the wear of the motor and machinery. Look for a capacity that is double or more than the weight that you need to move.

It's also important to consider the weight of any crane accessories that are being used. These accessories add to the total weight of the capacity and may limit how much you can actually move. Complete calculations for accessories like below hooks, chains, safety harnesses, and any materials used to carry things like liquids. Add those weights to the weight of the actual product to find an ideal capacity.


In any industrial setting, safety is extremely important. When shopping for an overhead crane, there a number of safety factors to consider before making the purchase. Take a little extra caution before the large device is installed in your facility. One of the main safety features to consider for your crane is cab control. Instead of being left out in the open, a crane operator can safely maneuver a crane through a special room installation known a cab control. The room features all of the controls, safety shut-off switches, and full window views of the crane for proper operation. If the crane operates at high speeds, then a cab control is often recommended to help prevent unnecessary injuries.

Another safety precaution to consider is lighting in your business. When a crane is installed, it can block out lighting fixtures hanging from the roof or force them to be removed completely. Consider new lighting placements or shop for cranes that feature lighting fixtures on them. Extra lighting is a great safety feature and can help reduce injuries caused by poor visibility.

By breaking down your crane options into different components, it's a lot easier to choose the ideal crane for your needs.

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