| Coupling Size | Torque Nm | Max. Speed (RPM) | Bore Dia MIN | Bore Dia MAX | QTY N | A | B | C | D | E | F |
|---|---|---|---|---|---|---|---|---|---|---|---|
| FBC 5 | 1662 | 2600 | 25 | 80 | 6 | 225 | 157 | 76 | 5 | 115 | 114 |
The Flexible Bolt Coupling FBC 5 represents a transition into the heavy-duty range of the FBC series. With a significantly increased outer diameter and a reinforced six-pin configuration, it is designed to handle high-torque industrial drives while maintaining a safe operating speed for most standard industrial motors.
Nominal Torque Capacity: 1,662 Nm
Maximum Speed: 2,600 RPM
Bore Diameter Range: 25 mm – 80 mm
Quantity of Pins (N): 6
Outer Diameter (A): 225 mm
Overall Length (B): 157 mm
The FBC 5 utilizes six high-load pins (N=6) to transmit power. At this size, the coupling provides a substantial mechanical advantage due to its 225 mm outer diameter, allowing it to safely transmit 1,662 Nm of torque.
The torque is transferred from the driving flange to the driven flange through the compression of heavy-duty elastomeric bushes. This design allows for a "soft start" effect and provides a critical buffer that protects the drive train from:
Torsional Shock: Absorbing energy from sudden load changes.
Misalignment: Accommodating up to 5 mm of axial gap (Dimension D) and significant angular/parallel deviations.
Resonance: Shifting the natural frequency of the drive string to prevent destructive vibrations.
Large Bore Versatility: Supports shaft diameters up to 80 mm, accommodating the large shafts found on high-horsepower motors and heavy gearboxes.
Superior Shock Absorption: The six-pin arrangement combined with larger bush volume provides exceptional damping for high-inertia loads.
High Torque-to-Size Ratio: Despite its power, the 225 mm diameter remains manageable for most industrial mounting frames.
Low Maintenance Cost: No lubrication is required. The "fit and forget" nature of the FBC 5 reduces downtime and eliminates the risk of oil leaks.
Extended Component Life: By isolating vibration, the coupling significantly extends the life of mechanical seals and bearings in the connected equipment.
Large Industrial Centrifugal Pumps: Standard for municipal water works and flood control stations.
Heavy Duty Agitators: Used in chemical and pharmaceutical mixing where high torque and steady rotation are required.
Stone Crushers & Aggregate Machinery: Acting as a mechanical fuse to protect motors from the shock of material processing.
Marine Auxiliary Drives: Powering generators and large winches on industrial vessels.
Paper and Pulp Mills: Ideal for drive sections in paper machines where reliability is paramount.
Speed Limitations: Note the maximum speed is 2,600 RPM. This is below the speed of 2-pole (3000/3600 RPM) motors; the FBC 5 is primarily intended for 4-pole or 6-pole motor applications.
Increased Hub Depth (Dimension C): The 76 mm hub length requires a substantial shaft extension. Ensure the shaft keyway is long enough to provide full engagement with the coupling hub.
Weight and Balance: Given its size (225 mm diameter), ensure the mounting structure can support the weight and that the shafts are properly supported to prevent overhung loads.
Gap Maintenance: Always verify the 5 mm gap (Dimension D) during installation to allow for thermal expansion of the shafts.
The Flexible Bolt Coupling FBC 5 is a robust, high-torque solution for heavy-duty industrial environments. By providing a 1,662 Nm torque capacity and supporting bores up to 80 mm, it offers the strength needed for demanding process machinery while maintaining the simplicity and maintenance-free benefits of the pin-and-bush design.
