CEMB N330, Руководство пользователя

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Judgment criteria on machine tool spindles (ISO 17243) C - 3
Vibration velocity parameter
The vibration velocity parameter is measured as the broadband vibration magnitude in
mm/s RMS , typically within the frequency range of 10 Hz to 5 kHz.
The vibration velocity parameter can be used as an indication of long term spindle
condition (LTSC).
The typical frequency range of 10 Hz to 5 kHz ensures that low frequency vibrations
from building movements, etc. are removed from the signal but still any unbalance
vibration (1 × running speed) from a 600 r/min spindle would be within the selected
frequency band. On the high end, the 5 kHz upper frequency limit allows for multiple
speed harmonics (as would be produced by, for example, a loosely mounted spindle)
on a 30 000 r/min spindle to be reflected in the evaluation parameter.
• Vibration acceleration parameter
The short-term vibration acceleration parameter is intended to reflect problems that
might lead to a catastrophic failure of the spindle within a reasonable short time
period, in most cases, ranging from days to six months.
The vibration acceleration parameter is measured as broadband vibration magnitude
in
m/s
2
RMS ; typically within the frequency range of 2 kHz to 10 kHz.
The vibration acceleration parameter can be used as an indication of short-term
spindle condition (STSC).
Spi ndle cl assification

Classification according to rated power
Direct-driven spindles and belt-driven spindles are divided into

spindles with rated power ≤ 5 kW, and

spindles with rated power > 5 kW

Classification according to maximum spindle speed
Four speed ranges are defined, with respect to spindle maximum speed, expressed in
r/min:

Speed range 1, SR1 600 < SR1 ≤ 6 000

Speed range 2, SR2 6 000 < SR2 ≤ 12 000

Speed range 3, SR3 12 000 < SR3 ≤ 18 000

Speed range 4, SR4 18 000 < SR4 ≤ 30 000
Note:
Spindle speed only affects the vibration evaluation zone boundaries for STSC
(vibration acceleration) and does not affect the zone boundaries for the LTSC
(vibration velocity)

Classification according to bearing type
Spindles are divided according to the following bearing types:

ball bearings (point contact);

roller bearings (line contact).