Description
WH5 WH Type Oldham Coupling – 25–32mm Bore Shock-Absorbing Sliding-Block Flexible Drive Coupling
The WH5 WH Type Oldham coupling is a sliding-block flexible drive coupling designed for applications transmitting 280 N·m at up to 4700 rpm where a certain degree of shaft relative offset compensation, shock absorption, and vibration damping capability are all simultaneously required. With a 100 mm outer diameter and bore range of 25–32 mm, it suits the full range of industrial shaft connections in this torque class — from compact instrument drives at the WH1 end of the series to large pump and processing equipment drives at the WH10 level. The coupling’s working temperature range of -20°C to +70°C covers standard industrial and outdoor service environments. Entering the medium-duty range of the WH series, the WH5 at 280 N·m covers the 25–32 mm bore class common in 1–4 kW motor output shafts. The coupling’s shock absorption characteristics are particularly valuable in pump and fan drive connections where startup torque peaks would otherwise reduce motor bearing life.
The WH Type coupling is a three-component sliding-block Oldham design: two identical metal hubs, each mounted on one shaft, and a central polymer slider block that simultaneously engages the tongue-groove features on each hub face. Torque is transmitted through the sliding contact between the polymer block tongues and the metal hub grooves. Relative radial displacement between the two shafts is absorbed by translational sliding of the block within the hub grooves during rotation. The polymer block material provides inherent shock absorption by deflecting elastically under peak torque loads, attenuating transient torque spikes before they are transmitted to the connected shaft and its bearings. This shock absorption characteristic distinguishes the WH Type from rigid Oldham couplings and makes it particularly valuable in drive applications with variable or intermittent loading.
Y-type (standard length) and J-type (short hub) bore configurations are both available for the WH5, with bore length dimensions of 62–82 mm (Y-type) and 44–60 mm (J-type). The full WH series documentation and selection guidance is available on our product catalog page.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | WH5 |
| Type | WH Type Oldham (Sliding-Block) Coupling |
| Bore Range (d) | 25–32 mm |
| Outer Diameter (D) | 100 mm |
| Inner Hub Diameter (D₁) | 70 mm |
| Slider Block Width (B) | 75 mm |
| Tongue Depth (C) | 27 mm |
| Y-Type Bore Length (L) | 62–82 mm |
| J-Type Bore Length (L) | 44–60 mm |
| Nominal Torque (Tn) | 280 N·m |
| Maximum Speed [n] | 4700 rpm |
| Working Temperature | -20°C to +70°C |
| Mass | 5.8 kg |
Dimension Reference
Hub and Slider Block Assembly
The WH5’s intermediate slider block is the functional core of the coupling. Machined from engineering polymer to precise tongue and groove dimensions, the block simultaneously engages the drive faces on both hub ends. The tongue width and groove dimensions on the WH5 are sized to provide adequate compressive contact area for reliable 280 N·m torque transmission while maintaining the sliding clearance needed for radial compensation movement during rotation. The tongue depth dimension C = 27 mm determines the shear plane geometry of the engagement and is a key parameter in the coupling’s shock absorption capacity.
Shock Absorption
The polymer slider block deflects elastically under peak torque loads, attenuating drive transients and protecting both motor and driven equipment bearings from shock loading. This is the primary functional differentiator of the WH Type over rigid Oldham couplings.
Shaft Offset Compensation
Radial shaft offset between the two connected shaft centrelines is absorbed by the sliding mechanism, preventing transmission of radial forces to motor or driven equipment bearings — reducing bearing overload and extending equipment service life.
Vibration Damping
The polymer block’s internal damping dissipates vibrational energy transmitted through the drive shaft, reducing vibration levels in both the motor and driven equipment — beneficial in applications where vibration affects product quality or equipment fatigue life.
Y and J Bore Options
Both standard-length Y-type and short-hub J-type bore configurations are available, accommodating applications with different axial space constraints between bearing supports.
Manufacturing
Typical Applications
- Small instrument and automation drive connections — servo and stepper motor output shaft connections with misalignment compensation and vibration isolation
- Printing and packaging machine drives — torque transient absorption during acceleration/deceleration cycles
- Medical and laboratory instrument drives — vibration damping for sensitive measurement equipment
- Conveyor feed drive connections — small format conveyor head drum connections with frame assembly offset
For application enquiries and volume supply, please visit our contact page.
Customer Reviews and Case Studies
★★★★★
Sweden — Pump OEM
The WH5 Oldham coupling connects motor to pump shaft on our self-priming pump product range. The coupling’s misalignment compensation eliminates precision baseplate alignment requirements, and the shock absorption smooths pump priming torque transients.
— Product Engineer, Gothenburg
★★★★★
Turkey — Agricultural Irrigation Equipment
Used on irrigation pump drive connections. The WH5 transmits the 280 N·m rated torque reliably in outdoor operating conditions from -20°C to +70°C — the full temperature range of our agricultural product.
— Mechanical Engineer, Konya
★★★★☆
South Africa — Mining Equipment
Fitted on small auxiliary pump drive connections at our platinum mine. The WH5 handles the variable torque loading of the auxiliary water pump and its vibration damping reduces drive noise in the confined underground installation.
— Maintenance Engineer, Rustenburg
Frequently Asked Questions
Is the WH Type coupling available in corrosion-resistant materials?
The standard WH Type coupling hubs are manufactured from cast iron or carbon steel. For corrosion-resistant requirements — stainless steel hubs, zinc-coated steel, or other materials — contact Ever Power to discuss custom material options. The slider block is already a non-metallic polymer and is inherently corrosion-resistant to most industrial environments.
What causes premature slider block wear in WH Type couplings?
Premature slider block wear is typically caused by: (1) operation above the rated torque; (2) shaft misalignment exceeding the rated compensation; (3) operation above the rated speed limit; (4) operating temperature outside the -20°C to +70°C range; (5) contamination of the tongue-groove surfaces with abrasive material. Maintaining alignment within specified limits and operating within rated parameters maximises block service life.
Does the WH Type coupling need to be dynamically balanced?
Standard WH Type couplings are not dynamically balanced as supplied. For applications approaching the maximum speed rating of the larger models (WH8–WH10), dynamic balance verification may be appropriate. At lower operating speeds typical of most WH Type applications, balance is not a concern. Contact Ever Power if dynamic balance certification is required.
What protective guard is recommended for WH Type couplings?
A close-fitting coupling guard is recommended for all WH Type installations to contain any slider block fragments in the event of block failure, and to protect personnel from contact with the rotating slider block that protrudes beyond the hub faces. The guard should allow ventilation airflow to prevent heat buildup at higher operating speeds.
Can the WH10 be used for large pump drives in water treatment plants?
Yes. The WH10’s 5,000 N·m torque rating and 80–100 mm bore range cover large centrifugal pump motor connections commonly found in water treatment and wastewater pumping installations. The coupling’s shock absorption is beneficial for pump start-up against system back-pressure, and the misalignment compensation reduces precision alignment requirements on wet well pump installations.
Enquire About the WH5 WH Type Oldham Coupling
Ever Power manufactures the WH5 and the complete WH Type coupling range — 10 models from WH1 to WH10 covering 16 N·m to 5,000 N·m — direct from our factory. Specify your bore diameter, bore type (Y or J), operating torque, and speed for a prompt technical and commercial response.
