What are the components of a double girder overhead crane?

Double girder overhead crane is an essential equipment in heavy material handling scenarios such as steel manufacturing in the mechanical production industry. Compared to the Single girl overhead crane, it has a higher lifting capacity, mostly ranging from 20 to 500 tons, and also provides a longer span, thanks to its key structural synergy. Understanding these crane accessories can help you effectively select cranes and operate them proficiently.

• Main beam: It is a pair of parallel steel structures similar to bridges that extend along the length of the crane. Its structure is a welded box girder, and the main beam is the main load-bearing structure of the bridge crane. They provide the stiffness and strength required for load-bearing and long span. Kinotranes uses advanced steel materials and perfect design to maximize the load-bearing capacity of the bridge crane and improve its performance.
• End beam: installed at both ends of the main beam, it consists of wheels that travel along the crane track beam, with a drive motor that has frequency control for smooth start and stop, as well as a gearbox and braking system responsible for moving the entire crane main beam along the workshop track.

Main beam

End beam

• Trolley Frame: This structure rides along rails mounted on top of the bridge girders. It carries the lifting mechanism.
• Lifting Mechanism: This is the heart of the crane's vertical movement.
• Hoist Trolley: A compact unit integrating a drum for winding the lifting medium (wire rope or chain), a powerful hoist motor, gearbox, brakes, and often a geared limit switch for precise height control. Kinocranes' European-style hoist trolleys are known for low headroom designs, maximizing hook height.
• Open Winch Trolley: Used for very heavy capacities (common above 32 tons, up to 500+ tons), this design features a separate winch mechanism mounted on the trolley frame, offering immense power and configurability.
• Lifting Medium: Heavy-duty wire rope is standard for most double girder cranes, wound onto the hoist drum. Hooks, sheaves/pulleys, and robust rope guides are essential parts of this system.

• Runway Beams: These are the fixed, heavy-duty steel beams, often I-beams or box sections, securely anchored to the building structure or supporting columns. They form the track upon which the crane's end carriage wheels travel. Precision installation is critical for smooth crane movement.
• Runway Rails: High-strength steel rails are fixed to the top of the runway beams, providing the precise running surface for the crane wheels.

• Cab Control or Pendant/Radio Control: Operators control the crane either from an enclosed cab mounted on the bridge or via a pendant station (hanging control box) or radio remote control from the floor. Kinocranes often design cabs for excellent visibility and ergonomics.
• Suspension cable system: This system provides power for the main beam of the crane and the running trolley. It is a cable that typically runs within a suspended tram/track system or along a closed conductor bar installed parallel to the runway.
• Control panel: It is an electrical component that manages power distribution and motor control based on operator operations, including contactors, relays, and drivers.

• Braking system: equipped with multiple safety braking devices, lifting the main brake, auxiliary brake, and brake on the drive of the motor.
• Limit switch: prevents overtravel operation, the upper/lower limit switch of the hook can stop the hook at a safe height, the limit switch at the end of the trolley prevents collision, and the limit switch at the end of the main beam prevents the entire crane from colliding.
• Load limiting device: Monitor the actual load to prevent overloading during transportation.
• Anemometer: suitable for outdoor use, automatically measuring wind speed to trigger an alarm or automatic shutdown.
• Buffer: Absorb the impact force of the main beam and trolley in a timely manner at the end of the journey.
• Walkway: Provide a safe passage for manual inspection and maintenance along the bridge beams.
• Hook: It is not integrated with the crane, but specialized accessories such as electromagnetic suction cups, grab buckets, C-hooks, or container hoists are usually present together with specific application functions of the crane.

The safety and service life of double girder overhead crane are directly related to the design, materials, and manufacturing quality of each accessory. Kinocranes manufacturer uses advanced steel, equipped with multiple braking and limit systems, and installs a frequency converter on the drive to achieve excellent control and energy saving, enabling the bridge crane to operate smoothly. Choosing cranes manufactured with high-performance components can ensure maximum normal operating time and personnel safety, reduce maintenance, extend service life, and lower operating costs. Therefore, it is very important to carefully check the specifications of these core components when choosing a double beam overhead crane.

Contact now