Description
WH3 WH Type Oldham Coupling – 18–22mm Bore Shock-Absorbing Sliding-Block Flexible Drive Coupling
The WH3 WH Type Oldham coupling is a sliding-block flexible drive coupling designed for applications transmitting 63 N·m at up to 7000 rpm where a certain degree of shaft relative offset compensation, shock absorption, and vibration damping capability are all simultaneously required. With a 70 mm outer diameter and bore range of 18–22 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. Mid-range in the WH series, the WH3 serves 18–22 mm shaft connections in the moderate-torque industrial drive class. Applications include textile machinery feed drives, small pump connections, and light conveyor drives where shock absorption reduces motor bearing fatigue under variable load conditions.
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 WH3, with bore length dimensions of 42–52 mm (Y-type) and 30–38 mm (J-type). The full WH series documentation and selection guidance is available on our product catalog page.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | WH3 |
| Type | WH Type Oldham (Sliding-Block) Coupling |
| Bore Range (d) | 18–22 mm |
| Outer Diameter (D) | 70 mm |
| Inner Hub Diameter (D₁) | 40 mm |
| Slider Block Width (B) | 60 mm |
| Tongue Depth (C) | 22 mm |
| Y-Type Bore Length (L) | 42–52 mm |
| J-Type Bore Length (L) | 30–38 mm |
| Nominal Torque (Tn) | 63 N·m |
| Maximum Speed [n] | 7000 rpm |
| Working Temperature | -20°C to +70°C |
| Mass | 1.8 kg |
Dimension Reference
Hub and Slider Block Assembly
The WH3’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 WH3 are sized to provide adequate compressive contact area for reliable 63 N·m torque transmission while maintaining the sliding clearance needed for radial compensation movement during rotation. The tongue depth dimension C = 22 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
- Compressor drive connections — reciprocating compressor peak torque absorption and motor protection
- Large conveyor drive shaft connections — belt conveyor head drum drive couplings with sustained high torque
- Processing industry pump drives — large centrifugal pump motor connections with thermal offset accommodation
- Wood and paper industry process drives — chipper, roll, and agitator drive connections with shock loading
For application enquiries and volume supply, please visit our contact page.
Customer Reviews and Case Studies
★★★★★
France — Textile Machinery
The WH3 Oldham coupling connects feed roller drives on our embroidery machines. The coupling’s shock absorption dampens the drive torque impulses from our stepper-driven feed system, reducing fabric tension variation.
— Design Engineer, Lyon
★★★★★
India — Food Processing Equipment
Used on small conveyor drive shaft connections in our food packaging equipment. The WH3 handles the operating torque reliably and accommodates the frame assembly misalignment of our modular packaging systems.
— Equipment Engineer, Pune
★★★★☆
Brazil — Agricultural Machinery
Fitted on seedling planting machine drive connections. The WH3’s vibration damping and misalignment compensation suit the variable load and rough operating conditions of our field-use planting equipment.
— Mechanical Engineer, Curitiba
Frequently Asked Questions
Does the WH Type coupling require lubrication?
Standard polymer slider blocks are self-lubricating — no external lubricant is required on the tongue-groove contact surfaces under normal operating conditions. For metal slider versions at elevated load, a small amount of molybdenum disulfide or equivalent dry film lubricant applied to the tongue-groove contact surfaces at installation can extend service life.
What is the angular misalignment tolerance for WH Type couplings?
The WH Type coupling accommodates a certain degree of angular misalignment between the connected shaft centrelines. The exact angular compensation value varies by model and should be confirmed with the product dimension documentation. For precision shaft connections, both angular and radial alignment should be within the specified limits to maximise slider block service life.
Is the WH Type coupling suitable for variable-speed drive applications?
Yes. The WH Type coupling is compatible with variable-speed drive (VFD/inverter) motor applications. The shock absorption properties of the slider block are particularly beneficial in VFD applications where rapid acceleration and deceleration cycles generate high drive torque transients. The coupling attenuates these transients before they reach the driven equipment.
Can WH Type couplings be supplied with non-standard bore sizes?
Yes, within the bore range specified for each model. If a non-standard bore diameter within the model’s bore range is required, specify the exact bore diameter and tolerance when placing your order. Bore sizes outside the model’s standard range require a custom design — contact Ever Power to discuss.
How does the WH Type coupling compare to a flexible jaw coupling?
Both the WH Type Oldham and jaw couplings provide shock absorption and misalignment compensation. The WH Type’s Oldham mechanism transmits torque at a constant velocity ratio regardless of offset angle — jaw couplings with spider elements introduce slight velocity variation under misalignment. The WH Type’s replaceable slider block also allows maintenance without hub removal, whereas jaw spider replacement typically requires some hub axial movement.
Enquire About the WH3 WH Type Oldham Coupling
Ever Power manufactures the WH3 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.
