• Jan 24, 2025
• News

Bridge Crane Components-Yuantai Crane

A bridge crane typically consists of several key components: a bridge ( single or double girder), end trucks, girders, a trolley, a hoist, and a control system.

Bridge cranes, commonly referred to as overhead cranes. They consist of numerous overhead crane components that work in unison to perform lifting, moving, and positioning tasks safely and efficiently. Understanding the individual overhead crane components and their functions can help ensure the best crane performance, proper maintenance, and extended crane service life.

Key Bridge Crane Components

The following is an introduction to the main components of an overhead crane and their respective roles and functions during crane operation:

1. Bridge Girder

The bridge girder forms the main structural element of the crane. It spans the width of the work area and carries the load. Depending on the application, cranes can have a single or double girder design:

• Single Girder: Typically used for lighter loads or smaller spans.
• Double Girder: Designed for heavy loads or wider spans, offering additional lifting height.

The girder's material and strength play a critical role in the crane's overall load-bearing capacity.

2. End Trucks

End trucks are located at either end of the bridge girder. These components house wheels that allow the crane to traverse along the runway system. End trucks come with motorized or manual drive mechanisms, ensuring smooth and controlled movement.

3. Runway System

The runway system consists of parallel beams fixed to the building structure, providing a track for the bridge crane to move along. The alignment and durability of the runway are crucial for safe crane operation.

4. Hoist

The hoist is the central lifting mechanism of the crane and is one of the most critical overhead crane components. It comprises the following:

• Drum or Chain: Wraps or unwinds to raise or lower the load.
• Wire Rope or Chain: The medium used to lift the load, chosen based on weight and application.
• Motor: Provides the mechanical force to lift or lower the load.
  Electric hoists are commonly used for bridge cranes, and their capacity can range from a few tons to several hundred tons.

5. Trolley

The trolley sits on the bridge girder and carries the hoist. It moves along the length of the girder, allowing the load to be positioned accurately within the crane's working area. Trolleys can be top-running or under-running, depending on the crane's configuration.

6. Control Systems

Modern overhead crane parts include advanced control systems that ensure precise and safe operation. These can be operated through:

• Pendant Controls: A handheld device connected to the crane, allowing manual control of movements.
• Radio Remote Controls: Wireless systems that offer enhanced mobility for the operator.
• Crane Cab: Crane cab is also one of the commonly used controls in overhead cranes. There are seats, consoles, air conditioning and other components in crane cab. Generally, the crane cab is mainly used on double girder overhead cranes, but if you have a need of it, we can also install it on single girder overhead cranes.

7. Electrical Components

The electrical system powers the crane and ensures smooth operation. Essential components include:

• Motors: Drive the trolley, hoist, and bridge girder.
• Contactors and Relays: Control the flow of electricity to different components.
• Electrical Panels: Consolidate and protect electrical connections.

8. Braking System

Cranes feature various brakes to ensure safety and control during operation. Key types include:

• Hoist Brakes: Stop the hoist from moving during lifting or lowering.
• Bridge and Trolley Brakes: Ensure the crane remains stationary when required.
  Braking systems are critical for maintaining load stability and preventing accidents.

9. Safety Features

Safety is a vital consideration in the design of overhead crane components. Standard safety features include:

• Limit Switches: Prevent the hoist or trolley from exceeding predefined travel limits.
• Overload Protection: Stops the crane from operating when the load exceeds its capacity.
• Anti-Collision Systems: Prevent cranes from colliding when multiple units are operating on the same runway.

Additional Features

1. Crane Electronic Scales

Modern cranes are equipped with load indicators that display the weight being lifted, helping operators avoid overloading.

2. Auxiliary Hoists

Some bridge cranes include auxiliary hoists for dual-load operations or fine load positioning.

The Importance of Proper Maintenance

Regular inspection and maintenance of bridge crane components are essential for safe and efficient operation. OSHA crane inspection guidelines recommend daily and annual inspections to ensure all parts are functioning correctly.

Annual Overhead Crane Inspection Form

A comprehensive inspection should include the following checks:

• Bridge girder integrity.
• Trolley and hoist mechanisms.
• Electrical systems and connections.
• Safety devices, including brakes and limit switches.

By addressing issues proactively, businesses can reduce downtime and extend the crane's service life.