The overhead crane is also known as the bridge crane. We often see them above the workrooms. They always move goods smoothly and orderly. Many people may have a question: "How does an overhead crane work?" This question is very interesting. Understanding the answer to this question can be helpful when choosing the appropriate overhead crane for your workplace. Next, we will analyze the components and operation principle of the overhead crane.
The components of an overhead crane
1. The Bridge
The bridge is the main horizontal beam that spans the work area. It carries the trolley and is supported by the end trucks.
- Single Girder Bridge: Uses one bridge beam.
- Double Girder Bridge: Uses two bridge beams for superior strength and stability.
2. The Hoist
The hoist is the heart of the lifting operation. It is the component that physically raises and lowers the load. Hoists can be powered by electric chains or wire ropes, each with its own advantages for different load capacities and speeds.
3. The Trolley
The trolley is the assembly that houses the hoist and moves it back and forth along the length of the bridge girder(s). This motion is known as cross travel.
4. The End Trucks
Located at each end of the bridge, the end trucks support the entire crane structure. They contain the wheels that allow the entire crane to travel along the runway rails installed on the building's support structure. This movement is called long travel.
5. The Runway
The runway is the fixed track system, usually mounted to the building's columns or support structure, on which the crane travels. It provides a stable and precise path for the crane's longitudinal movement.
6. Controls
The crane is operated via a control system. This can be a pendant station (a hanging control unit that the operator uses from the floor), a radio remote control for greater freedom and safety, or an operator's cab mounted on the crane itself.
Classification and Application of Overhead Cranes
- Top Running Overhead Cranes: The most common type. The crane bridge runs on rails mounted on top of the runway beams. They offer the highest lift heights and are designed for heavy-duty applications.
- Underhung Overhead Cranes: The crane bridge wheels run on the bottom flange of the runway beam, which is often supported by the roof structure. This design is excellent for facilities with lower headroom or for multi-crane systems.
- Freestanding Bridge Crane: A self-standing overhead crane, this is a lightweight type of bridge crane that uses flexible connections and is not constrained by the roof beams. It is suitable for workshops where the roof does not support the installation of bridge cranes.
The working principle of the overhead crane
In fact, the working principle of the overhead crane is quite simple. As we can see, the end beams at both ends of the bridge frame drive the main beam to move back and forth along the track, thus achieving the process of lifting, moving, and lowering.
There are three ways of movement:
1. Up and down vertical movement: The steel wire rope hook lifts the goods and moves the materials up and down.
2. Left and right lateral movement: The steel wire rope hook lifts the goods and moves the materials along the main beam left and right.
3. Front and back longitudinal movement: The steel wire rope hook lifts the goods and remains stationary, while the main beam moves back and forth along the runway.
Such flexible movement directions have created the flexibility and space utilization of the overhead crane.
How to Choose the Right Overhead Crane for Your Needs
Understanding how a bridge crane works is the first step. The next is selecting the right one for your specific application. Consider these factors:
•Load Capacity: What is the maximum weight you need to lift?
•Span: What is the required distance between the runway beams?
• Lifting Deight: The maximum distance that the load needs to be lifted after being hoisted?
• Working Frequency: How often does the overhead crane operate?
• Working Environment: Is the daily work workshop a special environment?
The best solution is often a custom one. At KINO CRANES, we don't just sell cranes; we provide custom lifting solutions. We can engineer a crane that integrates perfectly with your workflow.
