Shaft Alignment And Load - Danfoss EM-PMI375 User Manual

User Guide
EM-PMI375
Design principles
28 | © Danfoss | November 2021
Main dimensions of the electric machine
Ls Lf
Symbol Explanation
L Length of the electric machine frame (including the connection box(es).
F
L Length of the shaft (from the end of the shaft to the electric machine D-end mounting shoulder).
S
D Diameter of the flange mounting bore circle.
M
D Diameter of the mounting shoulder.
S
For all dimensions of the electric machine, see the product drawings.

Shaft alignment and load

Improper alignment (misalignment) may result in bearing overloads, premature bearing
failures, vibrations and shaft failures. Flexible coupling does not compensate for excessive
misalignment.
The type of the electric machine shaft is W50x2x24x8f. Recommended female connection counterpart is
of type N50x2x24x9H. The flange type is SAE3.
Alignment between the shaft and mating structure must be accurate.
The misalignment can be parallel or angular misalignment, or combination of those. With parallel
misalignment, the center lines of both shafts are parallel but they are offset. With angular misalignment,
the shafts are at an angle to each other. Figures below illustrate the parallel and angular misalignment.
Parallel alignment of the shaft and mating structure
30°
15°
BC265856307805en-000202