Franna cranes handle weight primarily through their integral chassis and counterweight design, combined with strict operational limits based on the principle of stability and structural integrity.
Since Franna cranes are designed to lift and transport a load without using traditional outriggers (stabilizing legs), their method of handling weight focuses on maintaining overall balance and a lower centre of gravity while the vehicle is in motion or static.
🏗️ Key Mechanisms for Weight Handling
Here are the critical components and principles that allow the Franna body to manage significant loads:
- Integrated Chassis and Boom: The boom is directly built into the vehicle chassis. The chassis itself is a high-strength structural frame designed to withstand the immense forces (both compression and tension) generated by the lifted load and the articulated steering.
- Counterweight: A substantial fixed counterweight (often built into the front body/chassis) is essential. This heavy mass offsets the load lifted by the boom, preventing the crane from tipping forward (loss of stability) or the rear axles from lifting off the ground.
- Pick-and-Carry Stability: When lifting and moving a load (pick-and-carry operation), the crane’s weight is distributed across its axles and tyres. The operator must adhere to specific load charts that dramatically reduce the safe lifting capacity when the crane is articulating (steering) or moving, as this shifts the centre of gravity and increases the risk of side-tipping.
- Articulated Steering: Franna cranes steer by pivoting in the middle (articulation) rather than having steerable front axles. This allows for excellent manoeuvrability but must be carefully controlled, especially when carrying a load, as excessive articulation or speed can generate side loads and cause instability or structural failure.
- Hydraulic System and Boom Strength: The telescopic boom itself is constructed from high-strength steel to handle the bending moment (leverage force) of the load. The hydraulic system manages the extension, retraction, and angle of the boom, transferring the load forces back into the main chassis.
We have a 20 tonne Franna ready to assist you if needed. Built strong, and ready to take the load on your next lift.