Description
WH2 WH Type Oldham Coupling – 12–18mm Bore Shock-Absorbing Sliding-Block Flexible Drive Coupling
The WH2 WH Type Oldham coupling is a sliding-block flexible drive coupling designed for applications transmitting 31.5 N·m at up to 8200 rpm where a certain degree of shaft relative offset compensation, shock absorption, and vibration damping capability are all simultaneously required. With a 50 mm outer diameter and bore range of 12–18 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. The WH2 occupies the light-duty bracket of the WH series, covering the 12–18 mm shaft size range common in small servo motors, fractional-horsepower drives, and light industrial equipment. Its 8200 rpm maximum speed suits direct motor shaft connections in conveyor, packaging, and printing equipment operating at typical motor speeds.
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 WH2, with bore length dimensions of 32–42 mm (Y-type) and 27–30 mm (J-type). The full WH series documentation and selection guidance is available on our product catalog page.
Technical Specifications
| Parameter | Value |
|---|---|
| Model | WH2 |
| Type | WH Type Oldham (Sliding-Block) Coupling |
| Bore Range (d) | 12–18 mm |
| Outer Diameter (D) | 50 mm |
| Inner Hub Diameter (D₁) | 32 mm |
| Slider Block Width (B) | 56 mm |
| Tongue Depth (C) | 22 mm |
| Y-Type Bore Length (L) | 32–42 mm |
| J-Type Bore Length (L) | 27–30 mm |
| Nominal Torque (Tn) | 31.5 N·m |
| Maximum Speed [n] | 8200 rpm |
| Working Temperature | -20°C to +70°C |
| Mass | 1.5 kg |
Dimension Reference
Hub and Slider Block Assembly
The WH2’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 WH2 are sized to provide adequate compressive contact area for reliable 31.5 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
- Industrial fan and blower drive shaft connections — motor offset compensation and startup torque absorption
- Pump drive connections — centrifugal and self-priming pump motor couplings with baseplate offset accommodation
- Agricultural machinery drives — field equipment variable load and shock absorption requirements
- Marine auxiliary equipment drives — hull flexure compensation and vibration damping in marine installations
For application enquiries and volume supply, please visit our contact page.
Customer Reviews and Case Studies
★★★★★
United Kingdom — Printing Machine OEM
The WH2 Oldham coupling connects our servo motor to the ink roller drive shaft. The shock absorption smooths drive torque transients during print head acceleration, reducing ink spread variation on the printed sheet.
— Design Engineer, Leeds
★★★★★
Italy — Packaging Machine OEM
Used on small format packaging line feed drive connections. The WH2 transmits our operating torque reliably and accommodates the assembly offset of our modular packaging equipment frames.
— Applications Engineer, Bologna
★★★★☆
South Korea — Semiconductor Equipment
Specified for wafer handling robot drive connections. The WH2’s vibration isolation prevents drive motor vibration from reaching the robotic arm structure, which would degrade wafer positioning accuracy.
— Mechanical Engineer, Suwon
Frequently Asked Questions
How is the WH Type coupling assembled?
The WH Type coupling is assembled in three steps: (1) mount and secure each hub on its respective shaft using the keyway and setscrew or clamping arrangement; (2) bring the shafts into approximate alignment with the coupling gap between hub faces; (3) insert the intermediate slider block tongue-and-groove features into engagement with both hub faces simultaneously. No special tools are required.
What bore types are available for WH Type couplings?
Both Y-type (standard cylindrical) and J-type (short hub) bore configurations are available. Y-type is the standard configuration; J-type uses a shorter hub length suitable for applications with limited axial space. Both bore types are offered for each model. Specify Y or J type when placing your order.
Is the intermediate slider block replaceable without removing hubs from shafts?
Yes. In most WH Type installations, the slider block can be removed and replaced without removing either hub from its shaft. Slide the hubs apart axially (if axial clearance allows) or, where axial movement is limited, partially loosen one hub and move it axially to release the block. Replacement blocks are available as spare parts for all WH Type models.
Can the WH Type coupling be used in outdoor applications?
Yes, within its rated temperature range of -20°C to +70°C. The metal hubs are not affected by outdoor exposure. The polymer slider block should be protected from prolonged UV exposure and from immersion in oils, solvents, or strong chemicals unless the specific block material has been verified for compatibility with the operating environment.
What is the maximum shaft bore for WH10?
The WH10 accepts shaft bore diameters from 80 to 100 mm. This covers the output shaft sizes of large industrial motors and gearboxes in the 100–500 kW power range.
Enquire About the WH2 WH Type Oldham Coupling
Ever Power manufactures the WH2 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.
