A disc type lamina coupling (also known as a steel lamina or diaphragm coupling) is a torsionally rigid, flexible coupling that transmits torque through thin, stainless steel metal discs. These couplings are designed to accommodate various types of shaft misalignment while maintaining zero backlash, making them ideal for high-precision motion control.
Key Features and Design
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Construction: Typically consists of two metal hubs (often aluminium or steel) and a flexible "disc pack" made of several thin sheet metal shims.
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Zero Backlash: The rigid connection ensures no play in motion, critical for servo and stepper motor applications.
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Maintenance-Free: Since there are no moving parts, these couplings do not require lubrication and are resistant to wear.
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Torsional Rigidity: High stiffness allows for precise positioning even at high speeds, sometimes up to 42,000 RPM in specialized designs.
Single vs. Double Disc Designs
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Single Disc: Comprised of two hubs and one disc pack. It can handle angular and axial misalignment but cannot accommodate parallel misalignment.
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Double Disc: Includes an additional centre spacer between two disc packs. This configuration allows each disc to bend independently, enabling it to compensate for all types of misalignment, including parallel offset.
Danum Couplings supplies a premium range of high-performance disc couplings for critical rotating equipment, engineered for precise torque transmission, low backlash, and high-speed operation. We provide industry-leading brands such as Rexnord Thomas, Bibby, KTR Radex and Flender Arpex with fast UK-wide supply.
DISC TYPE LAMINA COUPLINGS
Disc Type Coupling Brands
Rexnord Thomas
Rexnord Thomas Disc Couplings are torsionally rigid, all-metal flexible couplings designed for infinite life in motor, engine, and turbine-driven applications. They are lubrication-free and allow for visual inspection of the disc packs without disconnecting any equipment.
Popular Series & Applications
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XTSR52 & XTSR71: High-performance spacer couplings designed for easy installation and high torque density.
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XTSR52: A non-adapter style for general-purpose high-speed/torque use.
XTSR71: An adapter-style "drop-in" design that meets API 610 and API 671 standards for critical process pumps and compressors.
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AMR & CMR: Heavy-duty couplings for slow to medium-speed applications with high starting torque or shock loads.
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Series 52 & 71: Legacy spacer models known for reliability in power train systems.
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DBZ: A compact "legacy" coupling with inverted hubs for minimal shaft-to-shaft spacing.
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Miniature (C-Style): High-precision couplings for low-torque, small-scale applications.
Key Features
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Maintenance-Free: All-metal construction requires no lubrication.
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Misalignment Compensation: Handles angular, parallel (radial), and axial misalignment.
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Standards Compliant: Specific models meet API 610, API 671, and ATEX certification requirements for hazardous or critical environments.
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Tpack™ Technology: A unitized disc pack design that simplifies assembly and increases torque density.
KTR Radex
The KTR RADEX coupling is a backlash-free, all-steel laminae (disc) coupling designed for high-precision torque transmission. Known for being torsionally stiff and maintenance-free, it uses flexible steel laminae to compensate for shaft misalignments caused by factors like thermal expansion.
Key Features and Specifications
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Design: Features high-strength spring steel laminae sets typically in a waisted shape, optimized via FEM calculations for maximum torque and displacement.
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Torque Capacity: Available in ranges from 15 Nm up to 280,000 Nm.
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Temperature Range: Suitable for extreme conditions, typically operating up to +280 °C (and even higher in specialized designs).
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Maintenance: Completely maintenance-free and wear-free due to its all-metal construction with no moving parts that require lubrication.
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Configuration:
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Single-cardanic (NN): Accommodates angular and axial displacement only.
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Double-cardanic (NANA): Includes a spacer to also compensate for radial displacement.
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Variants of RADEX Couplings
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RADEX-N: The standard industrial series, widely used for pumps, fans, and compressors.
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RADEX-NC: A backlash-free servo coupling designed for high-speed, high-accuracy applications like servo technology.
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RADEX-N Composite: Features a spacer made of carbon fibre (CFRP) for large shaft distances without needing additional bearings, often used in cooling tower fans.
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Wind Turbine Series: Specialized high-torque versions capable of handling up to 300,000 Nm.
Flender Arpex
The Flender ARPEX is a torsionally rigid, all-steel multiple-disk coupling designed for high-performance applications where reliability and backlash-free torque transmission are critical.
Key Features
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All-Steel Design: Built from high-grade steel with stainless spring steel plates, making it wear-free and maintenance-free.
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Misalignment Compensation: Compensates for axial, radial, and angular shaft misalignments using flexible disk packs.
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Backlash-Free: Ensures high torsional rigidity, making it suitable for reversing operations and high-precision drives.
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Operational Range: Operates in extreme temperatures ranging from -60 °C up to +280 °C and supports nominal torques up to 10,000,000 Nm.
Common Product Series
Flender offers several specialized versions of the ARPEX coupling:-
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N-ARPEX (ARN): The latest evolution, offering higher torque capacity and speed. It consolidates previous series (ARS, ARC, ARP) into a more efficient range.
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ARPEX ARS-6: The universal standard series used for most general industrial applications.
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ARPEX ARC-8: Optimized for high-torque environments.
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ARPEX ARP-6: Specifically designed for pump drives and compliant with API 610/API 671 standards.
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ARPEX ARF-6: A compact version optimized for extremely restricted installation spaces.
Bibby Turboflex couplings
A Full range of Bibby couplings available on request.
Key Advantages
Torsional Rigidity
Engineered for absolute precision, the torsionally rigid construction ensures minimal rotational deviation. Its low-backlash design is specifically optimized for synchronous positioning in industrial drives.
All-Metal Build
Featuring a 100% metal assembly, these couplings eliminate the need for oil or grease. This robust design guarantees longevity and zero maintenance, significantly lowering lifetime operational expenses.
High-Speed Precision
Dynamic High Speed
Built for critical power transmission and high-velocity machinery, our disc couplings ensure operational stability. They provide the reliable performance required for the most demanding industrial drives.
Core Industry Sectors
Precision Compressors
Our disc couplings ensure centrifugal and axial compressors run smoothly by absorbing resonance and maintaining shaft alignment. This prevents costly component wear and ensures long-term stability.
Combined Turbinery
Designed for gas and steam turbines, these couplings manage extreme thermal growth and offset high axial loads. They provide a secure bridge that protects your delicate turbine blades and bearings.
Process Pumps
In critical pumping operations, disc couplings eliminate harmful vibration, extending the life of seals and motors. Their rigid yet flexible design handles misalignment without needing lubricant.
Naval drive systems rely on these couplings to dampen heavy vibrations and manage shaft movement at sea. Contact us for Rexnord Thomas, Bibby, or KTR Radex quote requests or a full data sheet.