Harbor cranes

Types of harbor cranes

The harbor crane is a special type of lifting machine used to transfer containers from ships to land and vice versa. They are mainly used for importing/exporting goods at seaports. Containers can be easily transferred to/from the ship using harbor cranes. The following are the most common types of harbor cranes used worldwide:

• Floating Crane:

  A floating crane is a specialized type of harbor freight crane integrated into a massive barge. This versatile piece of equipment is engineered to facilitate the loading and unloading of ships while they are anchored in open waters.

• Trailer-Mounted Harbor Crane:

  The trailer-mounted harbor crane is a versatile piece of equipment that can be transported to different locations by attaching it to a trailer. These cranes are commonly utilized in various maritime applications such as vessel unloading, container handling, and general cargo management. One of the standout features of the trailer-mounted harbor crane is its ability to be easily transported by road or sea to different locations where it is needed.

• Harbor Mobile Crane:

  A mobile harbor crane is an omnidirectional handling system that has been specifically designed for the bulk and container industries. This versatile and efficient piece of equipment is capable of meeting any operational requirement with ease. Mobile harbor cranes are available in a variety of configurations to suit different handling needs and environments.

• Rubber-Tyred Gantry Crane (RTG):

  The RTG crane is a harbor crane that uses wheels for movement. It's a gantry crane that can handle containers stacked on trailers or at ports with multiple horizontal and vertical lines of containers. Because they are more mobile than rail gantry cranes, rubber-tyred gantry cranes are well-suited for moving containers from ships to inland transportation networks.

Specifications and Maintenance of Harbor Cranes

Usually, a harbor or port crane's specifications will include its maximum lift capacity. This figure is probably the most vital piece of information for a cargo vessel. It reflects the heaviest weight of a single container the crane can handle. It does not mean that the crane can only lift containers of that weight. A crane with a 60-ton capacity will easily lift a fully loaded container that weighs less than 60 tons. However, if port authorities need to lift a container that weighs more than 60 tons, they may be able to offload its contents to bring its weight within the crane's capacity.

The maximum height from which a crane can or will safely lower cargo is usually referred to as its outreach. This is especially important for ship-to-shore cranes, as there may be restrictions on the height of cargo that can be safely lifted from a particular type of ship.

Other parameters include the following:

• Max Wheel Load: The maximum load of the wheels at the crane's base while it is stable and operational.
• Max. Wheel Load: The maximum load that can safely be lifted by the crane without causing structural damage.
• Overall Dimension: This is the physical dimension of the crane.
• Power: Unlike most other parameters, this one will change according to the type of crane. A mobile crane uses diesel power, whereas an electrical harbor crane would use grid power or that provided by a hybrid or battery system.

Maintenance:

The correct operation and maintenance of harbor cranes ensure port logistics run smoothly. Regular servicing is equally important to avoid delays or accidents. In addition to regular scheduled maintenance, some tips include the following:

• Before commencing operations, all components of the crane should be checked for any signs of wear, damage, or loose parts. All moving parts should be lubricated as per the manufacturer's specifications.
• The safe load capacity should be clear, whether it's a physical sign or part of the SCADA system function. The crane operator must be familiar with the crane's role and capacity.
• The operator must always unload cargo first before moving bulk items to storage areas or containers.

Scenarios of harbor cranes

As the primary loading and unloading equipment for various goods and containers at ports, the application scenarios of harbor cranes are as follows:

• Container Cargos: At container terminals, harbor cranes are primarily used to load and unload massive containers from large ships. They can take multiple containers at once, and by moving horizontally along the quay, they can position themselves directly over any containerized cargo ship.
• Bulk Cargos: Harbor cranes that are equipped with specialized attachments or devices may be used to handle bulk cargos, such as grain, coal, ore, and other loose materials at the commodity terminals. The conversion accessories employed are frequently suction pads, telescopic chutes, or buckets.
• General Cargos: At the general cargo terminal, harbor cranes typically handle packaged, project, and miscellaneous goods; heavy and oversized products were using strapping devices, hooks, or other rigging appliances.
• Cruise Ships and Ferries: Passengers and their belongings are transported from the terminal to the ship by way of harbor cranes equipped with passenger gangways and other specialized equipment.
• Oil and Gas Terminals: Offshore oil rigs and platforms as well as marine supply vessels are supplied with equipment and materials using harbor cranes at oil and gas terminals. To accommodate the specific requirements of offshore operations, these cranes may be fitted with specialized containers, such as clam shells, or beep containers.
• Construction and Infrastructure: At port construction sites, harbor cranes are used to erect port-related infrastructure, such as berths, jetties, and offshore structures. They are also responsible for assembling equipment and materials.
• Shipyard Operations: In shipyards, harbor cranes are used for ship building, repair, and maintenance operations. They may be used to assemble heavy sections of ships, install equipment, or carry out repairs and modifications.

How to Choose Harbor Cranes

Cargo management is crucial for the smooth operation of any harbor. To this end, harbor cranes are indispensable pieces of equipment. However, when purchasing these machines, it is imperative to consider the following factors to ensure that the right crane is chosen for the harbor's needs:

• Capacity and Supply Cargo Range: After understanding the type of cargo that must be managed, the maximum amount of weight must be lifted by the crane. Both factors must align. For example, if only containers and bulk ships are to be handled, a STS crane with enough capacity to handle them will be needed. However, if it is only for lighter goods, then an OHC or a mobile harbor crane may suffice.
• Harbor Infrastructure: The type of harbor must be considered and how the crane will fit into its infrastructure. For example, if the water at the harbor is not deep enough, an OHC is better. Similarly, if there is no room to move around, an OHC will work better. The crane's docking location and access must also be considered so that it can load/unload cargo smoothly.
• Operation and Control Systems: The crane also needs to be compatible with the harbor's operational systems. If the harbor uses remote monitoring of cargo management, a crane with similar remote control features will be needed. Additionally, if crew skill sets are a concern, the crane's ease of operation should be considered.
• Budget: Finally, the budget will determine whether it is a new crane or a refurbished one. If a new crane is to be purchased, its maintenance and resale value must also be taken into account when calculating the total cost.

By considering these factors and matching them to harbor requirements and budgets, the most suitable type of crane can be selected, and it will work efficiently in tandem with the rest of the cargo systems to facilitate trade and transportation.

FAQ

Q1: What are the recent trends in harbor crane design and construction?

A1: The latest trends in the design and construction of harbor cranes include increasing automation, sustainability and energy efficiency, smart port technology, and enhancements to operator safety and comfort.

Q2: What is the lifespan of a typical harbor crane?

A2: A well-maintained harbor crane can have a lifespan of 25-30 years or more.

Q3: What are the major components of a harbor crane?

A3: The main components of a harbor crane include the base, support structure, hoisting system, control system, and power supply system.

Q4: What is the difference between a pneumatic and hydraulic crane?

A4: Harbor cranes are often classified into two basic categories: fixed and mobile. A mobile harbor crane is a machine that can be moved around the port area to lift, transfer, and move containers. A mobile harbor crane operates by using the energy of wind and gas, and it is free to move around the port area. The mobile harbor crane uses a gas-powered engine that runs on natural gas to propel itself in the harbor. Gas turbines create high-pressure air, which is used to drive the turbine and propel the crane. Mobile cranes are large pieces of equipment that can be moved from one location to another. They are usually mounted on a chassis or a wheeled platform that allows them to be driven around the port area. A fixed harbor crane is a machine that is permanently installed in the port to lift, transfer, and move containers. The fixed harbor crane is usually mounted on a large concrete platform that is anchored to the ground. This type of crane is used to move large cargo ships that are anchored at sea and transfer containers from the ship to the shore or vice versa.