NBR flexible element
The source page identifies an NBR (nitrile rubber) buffer element and describes oil and wear resistance. It also states no lubrication is required.
NM Type Rubber Couplings · NM50–NM214
Compact torque transmission with an NBR flexible element.
Select from 5 to 1,000 N·m nominal torque using readable catalogue data, a complete sectional drawing and an RFQ process built around your two shaft diameters.
10 sizesNM50 through NM214
5–1,000 N·mCatalogue nominal torque range
1,500–3,000 rpmCatalogue limited speed values
19–95 mmCatalogue maximum bore range
Answer firstCatalogue exact Catalogue exact Engineering boundary
What this coupling is—and what the catalogue proves.
Misalignment capacity
Published radial allowance runs from 0.03 to 0.10 mm and angular allowance from 2.0° to 3.0°, depending on size.
Not a universal replacement
Matching the NM model name alone is insufficient. Confirm both shaft bores, keyways, hub length, outside diameter, torque, speed and actual shaft separation.
Selection path
Move from application duty to an approved bore drawing.
- Calculate or state continuous and peak torque.
- Confirm operating speed and start-stop duty.
- Check both shaft diameters against catalogue dmax.
- Specify keyway standard, bore tolerance and fixing method.
- Confirm temperature, oil exposure, guard and installation access.
- Approve the final manufacturing drawing before production.
High-resolution catalogue table crop. Click for full size.
Applications
Designed for compact industrial drive connections.
Pumps & fans
For motor-to-pump and motor-to-fan connections where moderate shock isolation and compact geometry matter.
Conveyors & packaging
For continuous-duty drives after torque, speed, bore and start frequency have been checked.
Mixers & general machinery
For guarded shaft connections where the NBR element's environment is compatible with the process.
Common questions
Fast answers before your RFQ.
What is an NM coupling?
An NM coupling is a compact flexible shaft coupling that uses an NBR rubber element between two hubs to transmit torque while accommodating limited misalignment.
Which sizes are documented?
The supplied catalogue documents NM50, NM67, NM82, NM97, NM112, NM128, NM148, NM168, NM194 and NM214.
Can you machine different bores on each half?
The catalogue marking example shows an NM67 with a 24 mm driving bore and a 25 mm driven bore, written NM67-24/25. Final bore, keyway and tolerance must be confirmed on the approved order drawing.
Does the coupling need lubrication?
The supplied catalogue states that this NM design does not require lubrication and is maintenance-free in that respect. Inspection and alignment checks are still necessary.