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Kop-Flex® high-performance couplings have been supplied to the global oil and gas industry for over 30 years and have amassed over one billion hours of reliable operation in API 671 applications. Leveraging this experience, the next generation of disc coupling was developed to enable continued improvements in the turbo-machinery equipment. Gas turbines and compressors are being designed for increased efficiency by leveraging smaller form factors and higher speeds, creating rotor-dynamic challenges. To achieve the best weight and power density possible, a more compact coupling was designed and optimized for the torque requirements of the application. Building on our foundation of reliability, safety and exceptional performance, the Kop-Flex® High-Performance Disc Coupling 2.0 was created for your highly engineered equipment. 


Product Cross Reference




  • Optimized disc geometry improves stress distribution and reduces reaction loads.
  • 15-30% weight reduction compared to our previous generation coupling.
  • Lowest overhung moment available.
  • Reduced coupling diameter decreases windage effects.
  • 22 sizes available to align with common inch and metric shafts.
  • Weight reduction decreases imbalance forces on equipment.

The next generation Kop-Flex® disc coupling is an evolutionary design developed using cutting edge analysis tools and techniques, including:


  • Advanced finite element analysis.
  • In-house static and dynamic testing.
  • Fatigue life testing.

Development leveraged our in-house R&D facility, which includes state-of-the-art test stands and precision instrumentation specifically designed for the development of next-generation coupling products. Analysis and testing complexity ranged from individual components to complete couplings to determine the product ratings met requirements. These improved analysis techniques enable technical details and in-depth analysis of application-specific designs to be delivered quickly and confidently.






The High-Performance Disc Coupling 2.0 product line consists of two reduced moment styles: the RMS and RZS. The RMS is a full-featured disc coupling providing a reduced windage design and interlocking flanges for additional protection in the event of a disc pack failure. The RZS coupling provides a more cost effective solution, with non-interlocking flanges. Optional coupling features also include:


  • Powerlign® torque meter
  • Lateral and torsional tuning
  • Electrical insulation
  • Shear device
  • Corrosion-resistant material


Shaft diameter drives the selection of reduced moment couplings for most high-speed equipment. The product line was designed with 22 sizes to match the most common inch and metric shafts, providing an optimized coupling selection for each application. The Kop-Flex® High-Performance Disc Coupling 2.0 is designed to be the lightest coupling available on the market, enabling the highest performance in critical applications.


disc coupling 



Compressor train for top oil and gas producer’s offshore project: 




The Kop-Flex® High-Performance Disc Coupling 2.0 selection enabled the customer to use a more cost-effective alloy steel spacer while still achieving a 15% weight reduction and meeting all application requirements.



Average weight reduction of over 30% compared to the previous generation.



RMS Disc Coupling (inch)


RZS Disc Coupling (inch)


RMS Disc Coupling (metric)


RZS Disc Coupling (metric)



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