Product Description




* Extremely resistant to wear, oil, CZPT and ageing
* Also resistant to hydrolysis (ideal for tropical climates)
* Protect the drive against dynamic overload
* Good physical properties
* Wide range of application
* Easy installation


Operating Conditions
Temperature : -35°C ~+ 100°C
Material : Rubber
Hardness : 90 -95 Shore A
Color : Black


  H Rubber Dimension (mm)  
size A B C D E F Thickness
A/B80  21 16 5 3 4 8 9
A/B95  25 21 8 7 4.5 11 12
A/B110  29 23 8 7 5 11 15
A/B125  32 27 8 7 5 12 18
A/B140  35 30 12 8 5 13 22
A/B160  36 30 12 10 6 17 24
B180  44 37 15 12 9 29 35
B200  48 42 19 17 11 34 43
B240 61 51 17 16 10 39 47
B250  44 37 15 12 9 29 35
B280  52 42 16 12 11 31 39
B315  48 43 18 18 11 34 41
B350 60 45 18 15 11 47 46
A180 36 30 12 10 6 17 24
A200 36 32 10 7 7 23 26
A225 41 34 13 9 8 24 31



About CZPT since 1984
HangZhou Melchizedek Import & Export Co., Ltd. is a leader manufactur in mechanism field and punching/stamp
ing field since 1984. Our main product, NMRV worm gear speed reducer and series helical gearbox, XDR,
XDF, XDK, XDShave reached the advanced technique index of the congeneric European and Janpanese produc
ts, We offer standard gears, sprockets, chains, pulleys, couplings, bushes and so on. We also can accept orders
of  non-standard products, such as gears, shafts, punching parts ect, according to customers' Drawings or sam-

Our company has established favorable cooperation relationships with sub-suppliers involving casting, raw mat-
erial, heat treatment, surface finishing and so on.

flexible coupling

How does a flexible coupling deal with backlash and torsional stiffness?

A flexible coupling deals with backlash and torsional stiffness in the following ways:

  • Backlash: Backlash refers to the play or clearance between mating teeth in mechanical systems. In certain couplings, such as gear couplings, some degree of backlash is unavoidable due to the space between the teeth. However, flexible couplings with elastomeric or beam-type elements typically have minimal to no backlash. The flexibility of these elements allows them to maintain continuous contact and transmit torque smoothly without any gaps or play between components.
  • Torsional Stiffness: Torsional stiffness is the ability of a coupling to resist rotational deformation or twisting under torque. It is essential to have adequate torsional stiffness in some applications to ensure accurate motion transmission and responsiveness. Flexible couplings exhibit a balance between torsional stiffness and flexibility. While they allow for a degree of angular and parallel misalignment, they still possess sufficient torsional stiffness to transmit most of the torque efficiently. This characteristic helps maintain the precision of motion control systems and prevents power losses due to deformation.

The design and materials used in flexible couplings contribute to their ability to address both backlash and torsional stiffness effectively. Here are some key features:

  • Elastomeric Elements: Couplings with elastomeric elements, such as rubber or polyurethane, provide excellent flexibility to absorb misalignments and dampen vibrations. They also exhibit minimal backlash as the elastomeric material maintains continuous contact between the coupling components.
  • Beam-Type Couplings: Beam-type couplings use thin metal beams to transmit torque. These couplings offer high torsional stiffness while still accommodating misalignments. The beams can flex slightly under torque, absorbing shocks and compensating for misalignment without compromising torsional rigidity.
  • Composite Couplings: Some flexible couplings use composite materials that combine the advantages of different materials to achieve specific performance characteristics. These composites can offer low backlash and precise torsional stiffness, making them suitable for demanding applications.
  • High-Quality Manufacturing: The precision manufacturing of flexible couplings ensures that components fit together with minimal clearances, reducing backlash. Additionally, high-quality materials contribute to better torsional stiffness and overall performance.

Overall, flexible couplings strike a balance between flexibility to accommodate misalignments and sufficient torsional stiffness to transmit torque efficiently. By effectively addressing backlash and torsional stiffness, these couplings contribute to the smooth and reliable operation of various mechanical systems.

flexible coupling

How does a flexible coupling handle torsional vibrations in rotating machinery?

A flexible coupling is designed to handle torsional vibrations in rotating machinery by providing a degree of flexibility and damping. Torsional vibrations are oscillations that occur in the drivetrain due to torque variations, sudden load changes, or other transient events. These vibrations can lead to resonance, excessive stress, and premature failure of components.

Flexible couplings mitigate torsional vibrations through the following mechanisms:

  • Torsional Compliance: Flexible couplings have an element, such as an elastomeric insert, that can deform or twist to absorb torsional shocks. When the drivetrain experiences torsional vibrations, the flexible element flexes, effectively isolating and dampening the vibrations before they propagate further.
  • Damping: Many flexible couplings have inherent damping properties, especially those with elastomeric components. Damping dissipates the energy of the torsional vibrations, reducing their amplitude and preventing resonance from occurring.
  • Tuned Design: Some flexible couplings are specifically designed with specific torsional characteristics to match the drivetrain's requirements. By tuning the coupling's stiffness and damping properties, engineers can ensure optimal torsional vibration control.
  • Torsional Stiffness: While flexible couplings provide flexibility to absorb vibrations, they also offer a degree of torsional stiffness to maintain the torque transmission efficiency between the shafts.

It is important to select the appropriate flexible coupling based on the specific torsional characteristics and requirements of the rotating machinery. Different applications may demand different types of couplings with varying levels of flexibility and damping. High-performance flexible couplings can effectively minimize torsional vibrations, protecting the drivetrain and connected equipment from excessive stress and potential damage.

Additionally, proper alignment of the flexible coupling during installation is crucial to ensure its optimal performance in mitigating torsional vibrations. Misalignment can introduce additional stresses and exacerbate torsional issues in the system. Regular inspection and maintenance of the flexible coupling will help identify any signs of wear or damage that may affect its ability to handle torsional vibrations effectively.

flexible coupling

How does a flexible coupling impact the overall reliability of connected equipment?

A flexible coupling significantly impacts the overall reliability of connected equipment in several ways:

  • Misalignment Compensation: Flexible couplings can accommodate both angular and parallel misalignment between connected shafts. By allowing for misalignment, the coupling reduces the stress and wear on bearings, seals, and other rotating components. This feature prevents premature failure of these components, contributing to improved reliability and extended equipment lifespan.
  • Vibration Damping: Flexible couplings possess inherent damping properties due to their elastomeric or flexible elements. These elements absorb and dissipate vibrations generated during the operation of machinery. By dampening vibrations, the coupling protects the connected equipment from excessive oscillations, reducing fatigue and preventing mechanical failures. This enhanced vibration control increases the reliability of the system.
  • Shock Load Absorption: In applications with sudden load variations or shock loads, such as in heavy machinery or high-speed equipment, a flexible coupling acts as a shock absorber. It can absorb and dissipate the impact energy, protecting the machinery from damage caused by sudden loads. The ability to absorb shock loads contributes to the overall reliability of the connected equipment.
  • Reduced Wear and Tear: The flexibility of the coupling minimizes stress and wear on rotating equipment. It allows for slight movements and misalignments, reducing friction and stress on bearings and other critical components. This reduction in wear and tear lowers the frequency of maintenance and replacement, increasing the overall reliability of the equipment.
  • Compensation for Thermal Expansion: Temperature changes in machinery can lead to thermal expansion or contraction of shafts. A flexible coupling can compensate for these thermal effects, ensuring that the machinery remains properly aligned even as temperature conditions fluctuate. This compensation prevents binding and misalignment, promoting reliable performance.
  • Protection Against Overloads: Flexible couplings help protect connected equipment from overloads and torsional vibrations. They act as a mechanical fuse, disconnecting the driveline when an overload occurs, thus preventing damage to expensive machinery. This safety feature enhances the overall reliability and reduces the risk of catastrophic failures.
  • Easy Maintenance and Alignment: Flexible couplings are designed for easy installation and alignment. This feature simplifies maintenance procedures, making it easier to inspect and replace couplings when necessary. Properly aligned couplings lead to improved equipment performance and longevity, enhancing overall reliability.

By compensating for misalignment, damping vibrations, absorbing shock loads, reducing wear and tear, and providing other protective features, a flexible coupling significantly improves the reliability of connected equipment. It extends the lifespan of critical components, minimizes downtime, and ensures smooth and efficient operation, making it a valuable component in various industrial applications.

China Professional Flexible Coupling Eupex Coupling Set/Rubber Element  China Professional Flexible Coupling Eupex Coupling Set/Rubber Element
editor by CX 2023-08-17