| Coupling Size | Torque Nm | Max. Speed (RPM) | Bore Dia MIN | Bore Dia MAX | QTY N | A | B | C | D | E | F |
|---|---|---|---|---|---|---|---|---|---|---|---|
| FBC 8B | 8729 | 1590 | 65 | 142 | 12 | 360 | 276 | 135 | 6 | 212 | 200 |
The Flexible Bolt Coupling FBC 8B is the pinnacle of the 8-series frame, engineered to provide maximum torque transmission through an eighteen-pin configuration (N=18). While it shares the same pin count as the 8A, it features reinforced flanges and a larger 370 mm outer diameter, pushing its capacity to a massive 8,299 Nm. This model is designed for the most demanding heavy-duty industrial drives where extreme power and absolute reliability are required.
Nominal Torque Capacity: 8,299 Nm
Maximum Speed: 1,550 RPM
Bore Diameter Range: 70 mm – 150 mm
Quantity of Pins (N): 18
Outer Diameter (A): 370 mm
Overall Length (B): 311 mm
The FBC 8B utilizes eighteen high-tensile steel pins arranged on a wide bolt circle. The increased outer diameter (370 mm) provides superior mechanical leverage, allowing the coupling to transmit 8,299 Nm while maintaining the flexibility of the pin-and-bush design.
Torque is transferred through the compression of the 18 elastomeric bushes. This high number of contact points ensures that the load is distributed incredibly evenly, which is critical for preventing "spot wear" on the bushes during high-torque startups. The design naturally accommodates axial, parallel, and angular misalignments, and the 6 mm axial gap (Dimension D) provides extra clearance for the significant thermal expansion often seen in large-scale machinery.
Highest Torque in Class: Offers over 8.2 kNm of torque, making it a robust alternative to larger, more expensive gear or grid couplings.
Massive Bore Capacity: Accommodates shafts up to 150 mm, fitting the largest industrial motor frames and heavy-duty primary drive shafts.
Maximum Vibration Isolation: The eighteen-bush layout creates a highly resilient barrier that effectively damps out the heavy torsional oscillations of high-horsepower systems.
Fail-Safe Redundancy: With eighteen pins, the coupling provides peace of mind; if one bush wears prematurely, the remaining seventeen continue to carry the load safely until the next service interval.
Zero Lubrication: Completely maintenance-free regarding oils or greases, making it ideal for the harsh, abrasive conditions found in mining and heavy manufacturing.
Primary Crushers & SAG Mills: Handling the extreme shock loads and massive torque requirements of ore processing.
Heavy-Duty Dredge Pumps: Connecting high-output engines to large-scale suction and discharge pumps.
Steel Mill Main Drives: Used in rolling, slitting, and forming lines where high reliability is non-negotiable.
Large-Scale Water Turbines: Powering massive hydroelectric or flood-control pumping systems.
Main Overland Conveyor Pulley Drives: Providing the necessary grip and torque for heavy-tonnage, long-distance material transport.
Speed Constraints: The maximum speed is 1,550 RPM. This is strictly for 4-pole, 6-pole, or 8-pole motors; do not use with high-speed turbine or 2-pole motor drives.
Deep Hub Engagement (Dimension C): The 152.5 mm hub length is the deepest in the series. It requires a significant shaft extension to ensure the key can safely distribute the 8,299 Nm load.
Weight and Rigging: At 370 mm wide and over 300 mm long, the FBC 8B is a very heavy component. Specialized lifting tackle and precision laser alignment are mandatory for a safe installation.
Axial Float: Carefully set the 6 mm gap (Dimension D). In large machines, axial shaft "hunting" is common, and this gap prevents the flanges from impacting one another.
The Flexible Bolt Coupling FBC 8B is a heavy-duty industrial titan. With an 18-pin design and a staggering 8,299 Nm torque capacity, it is built to handle the most rigorous power transmission tasks on the planet. Supporting bores up to 150 mm, it offers a simple, reliable, and lubrication-free solution for protecting massive industrial investments from vibration and misalignment.
