Shaft-hub connection

DIN 6892 Parallel Key Calculator

Verify a parallel-key connection under one-direction torque using approximate Method C.

DIN6892

Geometry and load

Parallel-key geometry

Shaft diameter d

Key width b

Key height h

Shaft keyway depth t₁

Key length lPF

Key formNumber of keys i

Load

Nominal torque Mtnom

Application factor KA–

Material strengths

Shaft yield strength

Hub strength

Key yield strength

Brittle hub (use Rm as strength)

DIN 6892:2025 · Methode C · one-direction torque only

Method C verification

Enter geometry and run Method C.

Approximate Method C

What this calculator does

Torque, application factor, key geometry, and material strengths provide bearing pressure, capacity, and required length.

Parallel keys are useful when assembly, removal, or repair matters. The simplified model suits predominantly one-direction, quasi-static torque.

Typical tasks

Coupling and gear hubs
Replaceable pulleys
Preliminary key-length sizing

Design notes and follow-up standards

Check before release

Load character

Reversing or impact torque requires a more detailed assessment than Method C.

Shaft and hub

Bearing pressure is only part of the verification; keyways weaken both components.

Product geometry

Select width, height, keyway form, and tolerances from DIN 6885.

Useful follow-up standards

DIN 6892 Method A/B

More detailed load distribution and component stresses for demanding cases.

DIN 743

Strength assessment of the keyed shaft under combined and alternating load.

DIN 6885

Standard key and keyway geometry for design and production.