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close this bookFeather Key Joints - Course: Techniques of Fitting and Assembling Component Parts to Produce Simple Units. Trainees' Handbook of Lessons
View the document(introduction...)
View the documentIntroduction
View the documentHints on Labour Safety
View the document1. Purpose of Feather Key Joints
View the document2. Kinds of Feather Keys and Profile Shafts
View the document3. Kinds of Feather Key Joints
View the document4. Stress on the Feather Key Joints
View the document5. Tools, Devices and Auxiliary Means
View the document6. Technological Processes for Manufacturing Feather Key Joints and Profile Shaft Joints
View the document7. Detachment of Feather Key Joints

4. Stress on the Feather Key Joints

Feather key joints are positive connections - the feather key sticks in a keyway that matches its form, without any preload.

As long as the machine parts are at rest, no forces are acting on the feather key, only when the rotary movement is started the rotary power is transmitted via the flanks of the feather key from one machine part to the other. The unit pressure at the flanks of the feather key acts on approximately half the height of the feather key. Opposite forces that are applied cause shear stresses at the level of the shaft circumference, which - with too high or discontinuously changing stress - may lead to the feather key shearing off.

Figure 9 Stress applied to the feather key joint

1 shearing stress, 2 applied forces, 3 rotary power

Changing rotary directions have to be avoided, because this may cause a wearing out of the keyway, so that the feather key does no more stick.

If highly stressed joints for alternating rotary directions are to be manufactured through, profile shafts must be used.

What kinds of feather key joints are distinguished?

What kind of stress is a feather key in a joint exposed to during the transmission of power?