A reliable crane is the backbone of heavy industry. Construction, energy, and manufacturing are all among the industries that depend on cranes to handle and assemble products.
Like any piece of industrial equipment, however, a crane needs to be designed with its intended application in mind. A crane that isn’t suited to a particular task or function can prolong production timelines, increase overhead costs, and pose a significant hazard to your workers, quickly negating any returns on the initial investment.
To ensure that they find the appropriate crane for their applications, most crane manufacturers provide their customers with detailed charts that outline and illustrate a crane’s capabilities. Understanding these charts will help you distinguish the strengths and shortcomings of a given set of cranes and help you select the best model for your company.
The Major Variables
A crane is a complex piece of equipment, affected by a wide range of conditions. Some of the circumstances that you should consider before investing in it include:
A crane needs to be sized with reference to your facility’s footprint and the spatial requirements of your typical applications. Having some knowledge of your usual materials and the space needed to assemble your products can help you determine the ideal height, radius, boom length, and hook height for your crane.
Not every crane can handle the same materials. Be sure to calculate the expected weight of a typical load within your facility before investing in a crane.
A crane needs to resist any occupational hazards within the workplace. If a given material is particularly flammable, for example, any crane that handles it should be spark resistant and explosion proof.
Understanding the Load Chart
To ensure that users purchase the best crane for their application, manufacturers of cranes provide customers with a load chart that outlines a crane’s capabilities and limitations. Understanding a load chart’s contents will help you identify the ideal crane for your project as quickly as possible.
A load chart consists of several items related to a crane’s performance. We’ve briefly summarized their importance here, but each individual load chart should provide the equations necessary to calculate these factors yourself:
Weight and Dimensions
A load chart lists a crane’s dimensions when it is and isn’t in use. It also provides the crane’s total resting weight and the load that should be placed on each axle of the trailer used to transport it.
The lift capacity is the necessary boom length while the crane’s outriggers are extended when a known counterweight is present.
Example: If you need to move an object that weighs 72,800 pounds over 26 feet with 8.8 tons of counterweight, the length of the boom should be 52.8 feet.
The lift range is the boom length needed to raise an object to a certain height after picking it up at a certain distance.
Example: If you lift an object that’s 33 feet away from a crane up 72 feet, the length of the boom should be 77.6 feet.
The lift angle is the maximum load that can be raised by a crane when it’s positioned at a certain angle.
Example: If a jib crane is positioned at a 15-degree angle, it can carry an object that’s 31 feet away from it if it weighs less than 9,000 pounds.
The Necessity of Crane Charts
Crane charts are an essential component of the procurement process, providing you with all of the information you need to make a sound decision. The ability to read them can streamline your company’s search and eliminate any misunderstandings between client and manufacturer, ensuring that your company receives the best crane for its applications.
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