Cranes, particularly overhead cranes, are one of the most common sights on any construction or demolition site. Materials can be lifted to great heights, and their rotating axes allow for great range within a construction site. Nevertheless, cranes are not a universal choice for construction projects. Below are some scenarios where perhaps a crane is not practical for your project, along with some equipment alternatives.
Situations Where a Cranes is Not Practical
While every construction job is unique, below are some common scenarios when cranes may not be the best equipment for your project.
- Plane Layout: Large projects require multiple pieces of equipment, including multiple cranes. In these cases, it’s imperative to consider the plane of each crane. The intersection of these planes can lead to inefficient use of time if one crane has to wait for the other move out of the way. This also increases safety risks, as there is the potential for cranes to run into each other.
- Size: Due to the size of cranes, their use might not be appropriate for your project. If all work is being done on or near ground level, crane use could lead to an inefficient use of time.
- Local Climate: When planning what equipment to use for your project, it’s necessary to consider the site’s climate and terrain. Heavy winds can affect the load the crane is lifting and the crane itself. Ground pressure must also be checked to make sure the ground can support the weight of the crane. Temperature can also affect the integrity of crane components, such as the crane block. In these instances, the working load limit can be affected, leading to an increase in overall time on the project.
- Electrical Hazards: Due to poor planning and safety guidelines, accidents can occur when cranes come into direct contact with a power source. This can result in electrocution of the worker guiding the load or anyone touching the crane. When deciding what equipment to use for your project, consider what power sources might put workers at risk with use of a crane. While safety guidelines and proper planning address these issues, consider if cranes are the most practical equipment to be used for your project.
Alternatives to Cranes
While several alternatives to cranes are available, below are two examples that show how crane limitations can be addressed:
- Modular Lift Towers: Comprised of a modular column and lacing framework tower system. These towers offer a variety of configurations, such as gantries, stand jacks and hoist systems. Due to their containerized construction, their height can be adjusted appropriately for the project. Setup time is the same as cranes, and mobilization costs are low relative to lifting capacity.
- Excavators: Vehicles equipped with digging buckets connected to the end of an extendable arm. Excavators can be used for a variety of purposes, such digging holes, demolishing buildings, and lifting heavy supplies. If the height of your project doesn’t justify a crane, consider an excavator.
Alternatives to Overhead Crane
While the overhead crane might not be practical for your particular project, this doesn’t mean all cranes should be ruled out. Other types of cranes are available that, like other equipment,
- Jib Crane: Crane comprised of a rotating horizontal boom attached to a fixed support (ground or building frame). Jib cranes can be used to serve equipment outside the range of an overhead crane. For production or assembly lines, multiple jibs can be positioned to have overlapping ranges and move materials along.
- Gantry Crane: Crane built onto a gantry. Gantry cranes can be used when overhead cranes would interfere with operations, storage space, service areas and other equipment.