Cranes are the backbone of heavy lifting in construction, engineering, and industrial operations worldwide. From the ancient origins of the principle to the sophisticated mobile cranes used on South African industrial sites today, cranes have evolved dramatically — but their fundamental purpose remains the same: to lift, lower, and move loads that are too heavy for manual handling. This guide explains what cranes are, the main types used in industrial rigging, and how to choose the right crane for your project.
What Is a Crane?
A crane is a machine used to lift, lower, and move heavy loads. Cranes work on the principle of mechanical advantage — using a combination of structural geometry, counterweights, and mechanical systems (wire rope, hydraulic cylinders, or chain drives) to multiply the force applied by the prime mover (typically a diesel engine or electric motor) and apply it as lifting force at the crane’s hook. Modern cranes can lift loads from a few hundred kilograms to several thousand tonnes, depending on their design and configuration.
What Are the Main Types of Cranes Used in Industrial Rigging?
Several distinct crane types are used in South African industrial and construction operations:
- Mobile cranes (all-terrain and rough-terrain) — road-mobile cranes with telescopic booms that can be rapidly deployed to any location. Used for the majority of industrial rigging operations in South Africa. Available in capacities from approximately 20 tonnes to over 1,000 tonnes.
- Tower cranes — fixed cranes mounted on a mast, used for high-rise construction projects. The slewing jib provides wide horizontal reach around the mast. Must be erected and dismantled using mobile cranes.
- Pick-and-carry cranes — compact mobile cranes designed to pick up a load and carry it while moving on the crane’s own wheels. Used in confined spaces and inside buildings where larger cranes cannot access.
- Overhead (bridge) cranes — cranes mounted on rails running along the length of a building, providing lifting capability at any point within the building footprint. Common in manufacturing and process facilities.
- Crawler cranes — cranes mounted on tracked undercarriages, providing stability on soft or uneven ground without outriggers. Used for very heavy lifts and on sites with poor ground conditions.
How Do You Choose the Right Crane for an Industrial Project?
Choosing the right crane for an industrial project requires matching the crane’s capacity at the required radius with the load to be lifted, ensuring the crane type is appropriate for site access and ground conditions, confirming that the crane can achieve the required hook height, and verifying that the crane can be positioned to provide the required reach without obstructions. A professional rigging company will select the appropriate crane type and configuration as part of the lift planning process — and will never attempt to use a crane that is at or near its rated limits without a robust safety margin.
Reef Rigging operates its own crane fleet for industrial projects across South Africa. Explore our cranage services or contact the team to discuss your lift requirements.
Frequently Asked Questions: Cranes in Industrial Rigging
Why does a crane’s rated capacity decrease at longer boom extensions?
A crane’s rated capacity is determined by the load moment — the product of the load weight and the horizontal distance from the crane’s slewing axis to the load (the radius). As the boom is extended or the radius increases, the load moment increases for the same load weight. This imposes greater structural stress on the boom, the slewing ring, the outriggers, and the crane’s ground supports. Crane load charts show the maximum permissible load at each combination of boom length and radius to keep these stresses within safe limits.
What is the difference between a crane’s gross capacity and its net lifting capacity?
A crane’s gross capacity is its total rated capacity at a given boom configuration and radius. The net lifting capacity — the maximum weight of load that can actually be lifted — is the gross capacity minus the weight of the lifting block, hook, wire rope, and all rigging hardware. On large cranes, the combined weight of these items can be several tonnes, which significantly reduces the net available capacity for the load itself. The rigging team must always deduct these weights from the gross capacity to determine whether the crane can safely lift the intended load.
How far in advance should I book a crane for an industrial project in South Africa?
For standard industrial crane requirements, booking two to four weeks in advance is typically sufficient. For large cranes (100 tonnes capacity and above), specialised cranes, or peak demand periods, four to eight weeks or more may be required. For very large or unusual projects — such as heavy-lift cranes of 500 tonnes or more — lead times of several months may apply. Contact your rigging contractor as early as possible to confirm crane availability and include it in the project programme.