What Is The Gantry Crane?

A gantry crane is composed of mechanisms for lifting, tilting, luffing, and traveling. The rotating part houses the first three components, which participate in every cycle. The rotating portion is equipped with an adjustable single boom and/or combined boom. The working position of a crane is adjusted using the traveling mechanism installed in the bottom of a portal. The addition of telescopic conveyors and telescopic tubes to portal cranes with grabbers increases productivity in handling bulk materials. As well as electrical protection, these cranes are also equipped with lifting capacity or moment limiters. Crane rail clamps are another safety device.

Classifications Of Gantry Cranes

1. Gantry cranes with grabs/hooks for loading or unloading are commonly used in port and open-air warehouses. The lifting capability is not higher than 25 tons. Because they work at a high rate, productivity is a major factor.

2. Portal cranes: Typically used on slipways and floating docks. They can be used to perform tasks such as hull construction and equipment installation. The maximum lift capacity is 300 tons. This decreases, however, as the working radius increases. Lifting speeds can be varied, which allows for faster lifting with lighter loads. Some working devices are fitted with micro-movement mechanisms to comply with installation requirements. While larger portal cranes can lift higher and work with larger radii and heights, their productivity is lower.

3. Portal cranes in construction and installation. Mainly used by hydropower stations and for tasks such as lifting prefabricated components, equipment, or dams. Their lifting capability and working speed fall in between the first two crane types. They are well-suited for disassembly, transportation, and assembly. They have a large hook depth and adapt easily to temporary operations and work on trestles.

How To Choose the Right Gantry Cranes?

Single-girder and double-girder cranes

For a lifting capacity of less than 50 tons or a span under 35 meters without special usage needs, a single girder gantry is recommended. A double-girder is recommended if a wider leg width or higher speed of work is required.

Span and Overhang Length

The span (or length) of a gantry is a critical factor that impacts the crane's overall weight. The span should be kept as low as possible when selecting the crane. This is provided that the requirements for equipment use and span standards are met.

Calculation of Gantry Crane Dimensions

During operation, there should be an appropriate space dimension between the external dimensions of a gantry crane and the goods and vehicle channels in the warehouse to facilitate loading/unloading operations. In general, when vehicles are unloading and loading within the span of the gantry crane, they should keep their distance from the legs at more than 0.75 meters. When the lifting equipment isn't in use, it should keep a distance of at least 0.5 metres. When goods are passed through the legs, there should be at least 0.5 meters between them.

How can gantry crans be protected from rust?

In the case of cranes that are idle for long periods, rust control is essential. So how do you rust-proof them when they've been idle for some time?

1. Before shutting down the equipment for maintenance, you must inspect the entire equipment's surface. To ensure the best results, it is recommended that you paint all areas with surface paint.

2. If you find that there is damage to the paint on any part of the metal, this area should be cleaned well and coated with antirust spray or other antirust coatings. The coating protects the metal from rusting due to weather conditions.

3. During the rust-prevention process, don't overlook the moving parts that are so important. Use a -10 grade or -20 diesel to brush the moving parts of the crane. This method not only removes contaminants that can cause equipment corrosion, but also forms a protective oil film on metal surfaces.

4. After cleaning and lubricating the machine with diesel, it is recommended to also apply a layer lubricating oil. If you want to maintain machinery performance, it is best to use a calcium or lithium-based lubricant. These greases will also be relatively easy for you to remove once the equipment is re-used.