Flange Star Spider Coupling: Structure, Specifications and Parameters

Flange Star Spider Coupling: Structure, Specifications and Parameters

Introduction to Flange Star Spider Coupling

The flange star spider coupling is an elastic coupling widely used in mechanical transmission systems. It achieves flexible connection between two shafts (such as motor, reducer, pump equipment shafts) through flange connection, combining torque transmission, relative displacement compensation, and shock absorption functions. While this flexible coupling serves different purposes than a cardan shaft or cardan universal joint, it offers unique advantages in applications requiring vibration damping and minor misalignment compensation.

Structural Composition

The flange star spider coupling mainly consists of three components working together:

1. Flanged Half-Couplings (2 pieces)

  • Material: Typically gray cast iron (HT200), cast steel (ZG270-500) or 45# steel (for high-precision applications), providing high strength and rigidity

  • Structure: Both half-couplings feature flange plates (for connection to equipment shaft ends) with uniformly distributed “grooves” on the inner side (matching the elastic spider). The center contains shaft holes (machined according to equipment shaft diameter, with keyways or shrink disc connections)

2. Star Spider Elastic Element (1 piece)

  • Material: Mostly polyurethane (PU) or nitrile rubber, with silicone rubber for high-end models (resistant to high/low temperatures)

  • Structure: Star-shaped (with 3-6 evenly distributed “arms”) where the arms embed into the half-couplings’ grooves, transmitting torque and compensating displacement through elastic deformation

Main Performance Characteristics

1. Wide Torque Transmission Range

With nominal torque typically ranging from 10-5000N·m (depending on specifications), this flexible shaft coupling adapts to small-to-medium and medium-to-large transmission systems (such as fans, pumps, conveyor belts, etc.).

2. Excellent Displacement Compensation Capability

Thanks to the elastic deformation of the star spider element, it compensates for relative shaft displacement:

  • Radial displacement: 0.1-0.5mm (increasing with specification size)

  • Axial displacement: 0.5-2mm

  • Angular displacement: ≤1°30′ (avoiding additional stress on shaft systems due to installation errors or equipment vibration)

3. Vibration Damping and Cushioning Performance

The elastic element absorbs vibration energy (damping rate approximately 20%-30%), reducing the impact of shock loads (such as during start-up and braking) on equipment, thereby extending the service life of motors, bearings, and other components.

4. High-Speed Adaptability

Maximum allowable speed typically ranges from 3000-8000r/min (depending on material balance precision), meeting the speed requirements of most industrial motors (ordinary motor speeds below 3000r/min).

5. Easy Installation and Maintenance

Flange connection requires no axial movement space, making it suitable for various installation positions. The elastic spider is a wearable part that can be replaced without disassembling the half-couplings, resulting in low maintenance costs.

6. Environmental Adaptability

  • Operating temperature range: Polyurethane material -30℃~80℃, rubber material -20℃~70℃ (silicone rubber up to -60℃~200℃)

  • Oil resistance, aging resistance (polyurethane superior to ordinary rubber), suitable for general industrial environments (avoid long-term contact with strong acids and alkalis)

7. High Transmission Efficiency

Under normal operating conditions, transmission efficiency ≥98% with minimal energy loss, making it suitable for continuous operation systems.

Comparison with Other Flexible Shaft Coupling Types

While spider couplings excel in vibration damping and minor misalignment applications, other flexible shaft coupling types serve different purposes:

  • Cardan shaft and cardan universal joint: Ideal for large angular misalignments and high-torque applications

  • Tire shaft coupling: Superior for extreme shock absorption and large parallel misalignments

Each of these flexible shaft coupling options has distinct advantages depending on specific operational requirements.

Applications

Flange star spider couplings are widely used in:

  • Fan and blower systems

  • Pump and compressor drives

  • Conveyor systems

  • General industrial machinery requiring vibration damping

Why Choose ApexCoupling?

At ApexCoupling, we specialize in manufacturing high-quality power transmission components, including various flexible shaft coupling types. Our flange star spider couplings offer:

  • Precision manufacturing for reliable performance

  • Multiple material options for different environmental conditions

  • Comprehensive technical support for proper selection

  • Competitive pricing and timely delivery

In addition to spider couplings, we provide a complete range of power transmission products including cardan shaft systems, cardan universal joint components, and other flexible coupling solutions.


Looking for the right flexible coupling solution?
Contact ApexCoupling today for expert guidance on selecting the optimal coupling for your application. Our technical team will help you choose between spider couplings, cardan shaft systems, and other flexible shaft coupling types to ensure optimal performance and reliability.