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Small acetal coupling disc, inch size OD21/33, for high parallel misalignment

Ruland Manufacturing

Ruland Manufacturing OD21/33-AT Oldham Coupling Disc

SKU CH-6VW4-0B2DW

Acetal Oldham coupling disc handles 0.008 in parallel and 0.5° angular misalignment at 70 in-lb torque

  • Handles high parallel misalignment up to 10 percent of coupling OD
  • Angular misalignment capacity of 0.5 degrees for flexible shaft alignment
  • Maximum torque rating of 70 in-lb with 350 in-lb break torque
  • Acetal disc material provides 111.1 in-lb/Deg torsional stiffness
  • Operates at speeds up to 4,500 RPM with 0.006 in axial motion

Oldham Coupling Disc OD21/33

The Ruland OD21/33-AT disc is the replaceable centre element for an Oldham coupling. It transmits torque while compensating for parallel and angular misalignment between shafts in motion-control systems. The acetal construction provides low backlash and electrical isolation. Suitable for new builds or as a service part for existing Ruland hubs.

Engineers needing high parallel offset

This disc handles parallel misalignment up to .131 in and angular misalignment of .5 degrees, making it suited for applications where shaft alignment cannot be held tight. Axial motion of .006 in is also accommodated. It is not for designs that require zero backlash under reversing loads or for environments that attack acetal chemically. Buyers needing higher torque capacity or metallic discs should look elsewhere.

70 in-lb maximum torque rating

The disc is rated for 70 in-lb continuous torque with a break torque of 350 in-lb. Torsional stiffness is 111.1 in-lb per degree. Maximum speed is 4,500 RPM. These limits define whether the disc matches the application’s power and speed requirements. Check hub diameter of 1 21/64 in for compatibility with existing hubs.

Highlights

  • Handles high parallel misalignment up to 10 percent of coupling OD
  • Angular misalignment capacity of 0.5 degrees for flexible shaft alignment
  • Maximum torque rating of 70 in-lb with 350 in-lb break torque
  • Acetal disc material provides 111.1 in-lb/Deg torsional stiffness
  • Operates at speeds up to 4,500 RPM with 0.006 in axial motion

Specifications

No published specifications for this item yet.

Questions about this item

Will the acetal disc need scheduled replacement or lubrication?

The acetal disc runs dry and requires no lubrication; replace it only if visual inspection shows cracking, excessive wear or if torque transmission becomes erratic.

At continuous operation what limit appears first — the 4,500 RPM speed ceiling or the 70 in-lb torque rating?

The 70 in-lb maximum torque is the first limit; exceeding it risks disc deformation before the 4,500 RPM speed ceiling is reached.

How much heat and noise does the coupling generate when running all day at 4,500 RPM?

Acetal construction keeps noise low and heat minimal; the disc stays near ambient temperature with only a faint meshing sound at full speed.

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