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Compressor and Pump Couplings

The Kop-Flex® KD® coupling product line was designed for pump, screw and reciprocating compressor applications.  These high-value disc couplings are manufactured to finishes typically found on higher-cost offerings, providing simplified maintenance and best in class performance. The superior KS coupling product line is balanced to tighter tolerances for higher operating speeds and meets API 671 specifications

For over 30 years our High-Performance products have been the standard for reliability and performance. Our KD® and KS product lines use similar disc pack geometry and benefit from our experience in gas turbine and centrifugal compressor applications.

Kop-Flex® also offers resilient coupling designs which can be torsionally soft to isolate damaging vibratory torques or provide damping to minimize severe oscillations due to peak torques. The Max-C® replaceable rubber elements are available in various durometers in order to  tune  drivetrains away from damaging resonant frequencies.



Talk to one of our expert sales professionals about how our solutions can efficiently power your business.



Product Cross Reference



kopflex


KD® PRODUCT LINE OVERVIEW

The KD® product line provides great value. The feature-packed KD20, KD21, and KD23 all come standard with the following:

Features

  • Fully Machined Construction
  • Scalloped Disc Profile
  • Stainless Steel Unitized Disc Pack
  • As Machined AGMA Class 9 Balance
  • Forged Steel Components

Benefits

  • Improves dynamic balance compared to cast components
  • Optimize stress distribution and reduces reaction loads
  • Higher strength and facilitates replacement of the flex element
  • Allows for higher operating speeds, Class 10 optional
  • Allows for smaller, lower weight couplings


kopflex


These factors combine to provide “best in class” torque capacity by size, allowing for the most power-dense coupling selection to be made.

KD® PRODUCT LINE OVERVIEW OPTIONAL FEATURES INCLUDE:

Torsionally Tuned Spacer
By machining a forging instead of using off the shelf cast components. The stiffness of the spacer can be adjusted to torsionally tune the coupling.


Shrink Disc Mounting
By incorporating a shrink disc mounted on the hub body the coupling can be installed or removed without heating the hubs.


Keyless Tapered Bushing
By using a tapered bushing, interference fit hubs can easily be removed through the use of hydraulic fittings and equipment.



KOP-FLEX® KD2®/KD20 COUPLINGS

The KD2® and KD20 are user-friendly spacer couplings designed to meet API 610 / ISO 13709. The medium-duty KD2® and the heavy-duty KD20 are for applications requiring moderate shaft separations. Installation and maintenance are simplified by the use of only three main parts: two hubs and a factory assembled center section.

  • Drop-out spacer style
  • Fully machined steel construction
  • AGMA Class 9 Balance standard
  • AGMA Class 10 or 11 Balance optional
  • Many sizes available to fit your application
  • Standard shaft separations for industrial applications
  • Many typical center section lengths stocked
  • For higher speed applications consider a KS coupling
kopflex


 

  1. Combined coupling ratings are based on simultaneous conditions shown. Contact Kop-Flex Engineering for maximum allowable values for your specific application.
  2. Standard keyed bores per ANSI/AGMA 9002. Contact Kop-Flex for other fit requirements.
  3. Max. bore for allay keyless hubs is given for reference only. Contact Kop-Flex Engineering with specific requirements.


Kop-flex Kd2 or Kd20 Couplings drawing


 

  1. Additional standard center assembly lengths are available as stock items. Custom lengths are also available, contact Kop-Flex for more information.
  2. Weight and Inertia are based on max. bore keyed standard hub, Hub Length "E” and Typical “C” Dimensions.
  3. Torsional stiffness is based on 1/3 shaft penetration method, max bore keyed standard hub. Hub Length “E" and Typical "C" Dimensions.


KOP-FLEX® KD21 COUPLINGS

The KD21 is an economical spacer coupling designed for pump applications. The unitized disc packs and close tolerance bolts provide good dynamic balance. The minimal number of components creates an economical disc coupling solution.

  • Economical spacer style
  • Fully machined steel construction
  • AGMA Class 9 Balance standard
  • AGMA Class 10 Balance optional
  • Many sizes available to fit your application
  • Standard shaft separations for industrial applications
  • Many typical spacer lengths stocked
  • For higher speed, applications consider a KS coupling
kopflex


 

  1. Combined coupling ratings are based on simultaneous conditions shown. Contact Kop-Flex Engineering for maximum allowable values for your specific application.
  2. Standard keyed bores per ANSI/AGMA 9002. Contact Kop-Flex for other lit requirements.
  3. Max bore for alloy keyless hubs is given for reference only. Contact Kip-Flex Engineering with specific requirements.


Kop-flex Kd21 Couplings


 

  1. Additional standard center assembly lengths are available as stock items. Custom lengths are also available, contact Kop-Flex for more information
  2. Weight and Inertia are based on max. bore keyed hub, Hub Length "E" and “Typical "C” Dimensions.
  3. Torsional stiffness is based on 1/3 shaft penetration method, max bore keyed hub. Hub Length "E" and Typical "C" Dimensions.


KOP-FLEX® KD23 COUPLINGS

The KD23 is a flywheel style coupling, designed for use on reciprocating equipment. The machined plate adapter is designed to connect to standard SAE flywheels.

  • Flywheel style
  • Fully machined steel construction
  • AGMA Class 9 Balance standard
  • Torque ratings optimized for compression industry
  • Many sizes available to fit your application
kopflex


 

  1. Combined coupling ratings are based on simultaneous conditions shown. Contact Kop-Flex Engineering for maximum allowable values for your specific application.
  2. Standard keyed bores per ANSI/ALMA 9002. Contact Kop-Flex for other fit requirements.
  3. Max. bore for alloy keyless hubs is given for reference only. Contact Kop-Flex Engineering with specific requirements.


KD23 Couplings Drawing


 

  1. Weight and Inertia are based on max bore keyed hub. Hub Length "E" and Typical “C” Dimensions.
  2. Torsional stiffness is based on 1/3 shaft penetration method, max bore keyed hub. Hub Length "E" and Typical “C” Dimensions
>


KOP-FLEX® MAX-C® CB COUPLINGS

The Max-C® CB is a resilient coupling used on reciprocating equipment to isolate damaging vibratory torques from connected equipment. Contact Kop-Flex® Engineering with specific application information so a custom-engineered and torsionally tuned Max-C® can be designed to your requirements.

  • Torsionally soft
  • Rubber block in cylindrical shape
  • Various durometers available
  • Custom engineered for applications
  • Maintenance free operation
  • Hybrid designs are available with disc, gear or diaphragm flex elements
  • For applications requiring a higher degree of torsional stiffness, consider a Max-C® WB. Contact Kop-Flex® Engineering for details
 
kopflex


CB Couplings table

 

    ① Space needed for block removal

    ② Number of blocks employed is shown in Tables No. 1 and 2

    ③ Vibratory torque values tabulated relate to vibration frequencies up to 500 vib/min. For higher frequencies, coupling vibratory torque capacity is derated on the following


Math Equation

Where

T = Vibratory torque capacity (lb. in.) at frequency F (vib/min.).

TF = Vibratory torque (lb. in.) from table.

F = Frequency (vib/min.) at which torque capacity is required.

 

CB Couplings drawing


 

    ④ A reduction in the maximum bore is required for limited end float couplings, please consult Kop-flex.

    ⑤ Weight and WR3 values are based on ductile iron hubs and sleeves, and steel forged rigid and end rings.

    ⑥ Max. speeds based on ductile iron. Greater speeds allayed for forged steel.



KOP-FLEX® ELASTOMERIC® COUPLINGS

A proven and unique concept for a non-lubricated “maintenance free” flexible coupling. The Elastomeric® provides long service life for the coupling, and equipment bearings and seals. The design concept provides low-cost power transmission with the added benefits of absorbing shock loads and damping damaging vibrations.

  • Cushions the shock of impact loading
  • Dampens torsional vibrations
  • Rubber in compression increases torque capacity over shear
  • Torsionally soft
  • Dynamically stable
  • Split insert facilitates installation
kopflex


 

  1. If actual maximum torque loads are known, do not use Service Factors but rather select coupling size under "Torque Rating" in Table I. These figures are those which the coupling is capable of transmitting under continuous operation and normal alignment so as to be consistent with reasonable industrial service life.
  2. For infrequently applied loads not to exceed once per hour.
  3. For higher speeds, refer to Kop-Flex.


ELASTOMERIC Couplings




KOP-FLEX® KS COUPLINGS

KS disc couplings are designed to meet API 671 specification requirements and provide a less expensive alternative when application speeds are in the intermediate range. They are typically used for turbine and motor drive applications, where the additional features of the High Performance product line are not required.

  • Economical API 671 solution
  • Drop out anti-flail center section
  • Dynamically balanced for higher speed applications
  • Rigid hubs allow for large bore capacity
  • Includes shims to facilitate axial alignment
kopflex


 

    ① To account for off-design fluctuating or continuous torques, an experience or application factor should be used. API 671 and Kop-Flex recommend a 1.5 minimum for general turbomachinery applications.

    ② Mass elastic data based on couplings with typical bores and 18 00" shaft separation up to #705, and min. C for #805 and #905; design and data can be changed to meet specific requirements. All major components are made of carbon steel.



Kop flex Ks Couplings drawing


 

    ① To account for off-design fluctuating or continuous torques, an experience or application factor should be used. API 671 and Kop-Flex recommend a 1.5 minimum for general turbomachinery application.

    ② Mass elastic data based on couplings with typical bores and 18.00" shaft separation up to #705, and min. C for #805 and #905; design and data can be changed to meet specific requirements. All major components are made of carbon steel.



KOP-FLEX® HIGH PERFORMANCE MP COUPLINGS

Kop-Flex® High Performance couplings satisfy the requirements for high speed applications. The marine style, MP High Performance Disc coupling is typically used on steam turbines, generators and compressors and meets API 671 specification requirements.

  • Higher torque capacity than KS product line
  • Full alloy steel construction
  • Removable center section
  • Improved anti-flail design
  • Rigid hubs allow for large bore capacity
  • Reduced windage disc pack cover
kopflex


 

General Notes: ① Based on 1.5 hub O.D./ bore ratio; larger bores we possible, consult Kop-Flex for specific applications.

    ④ API 4th Edition Rating (0.2 degrees misalignment with full axial misalignment capacity).

    ⑤ Maximum momentary torque capacity as defined by API 671 is used to evaluate applications such as generators with short circuits. RM and MS interlocking flanges can be modified, along with the rest of the coupling, to accommodate capacities 1.5 times this value.

    ⑥ Data based on coupling with 18' shaft separation and nominal tapered bores for keyless hydraulic shaft connections; data can be changed to meet specific requirements.

    ⑦ Kop-Flex torsional stiffness calculation.



KOP-FLEX® HIGH PERFORMANCE RZS COUPLINGS

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. To achieve the best weight and power density possible, the coupling diameter was reduced while the torque capacity was aligned with the application. The HPD2.0 design is the lightest coupling available on the market, improving equipment performance in the most critical applications.

  • Optimized disc geometry improves stress distribution
  • 20-30% weight reduction over previous generation
  • Lowest overhung moment available
  • Reduced OD improves balance and reduces windage
  • 22 sizes driven by common customer shafts


kopflex

 

    ① 4th edition Rating (0.2 degrees misalignment with full axial misalignment capacity).

    ② Maximum momentary torque capacity as defined by API 671 is used to evaluate applications such as generators with short circuits. Other large noncontinuous torques, called Transient torques in API 671, such as induction and synchronous motor start-ups, are evaluated using low cycle fatigue analysis. The magnitude and frequency of this transient (peaks) are required information. The transient capacity of Kop-Flex High-Performance disc couplings is 1.2 times the max. continuous coupling rating for 10.000 cycles.

    ③ Data based on coupling with 18” shaft separation and nominal tapered bores for keyless hydraulic shaft correction, data can be changed to meet specific requirements.

    Kop-Flex torsional stillness calculation method.

    Specifications and selection data are subject to change without notice

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