Makino V55, Руководство по обслуживанию

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4V2A1563 (E) 6 - 5
6.3.1 Spindle Power and Torque
Figure 6-2
shows the 14,000 and 20,000 rpm spindle power and torque
characteristics in relation to speed (rpm). The solid lines show the motor's
continuous rating and the dashed lines show the motor's 15 minute duty
rating.
EXAMPLE:
The 14,000 rpm graph (continuous rating) shows spindle power climbing
and maximum torque, from the minimum rpm up to the base speed of each
motor winding. The base speed of the low speed winding is 1500 rpm and
the high speed winding is 5000 rpm. From 5000 to 10,000 rpm, the high
speed winding is active and power remains constant, but torque drops off.
From 10,000 to 14,000 rpm both power and torque drop off. This indicates
the need to program cutting conditions to use the spindle's power, rather
than its torque. High-speed machining whether in steel or graphite, should
require low load conditions and therefore benefit from high power rather
than high torque characteristics.
Spindle Side Load
High-speed spindle bearings are susceptible to high radial thrust (force) and side load
(moment). Exceeding the allowable force and moment limits of the spindle will; reduce
tool life and part finish and cause premature bearing failure.
See
section 6.4
for more detail on tooling balance, concentricity, overhang and force
and moment calculations.
F
IGURE
6-2
SPINDLE POWER AND TORQUE CHARACTERISTICS