Harig AUTOMATIC PLC, Руководство пользователя

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ccasionally, due to a phenomenon called
fretting corrosion
(usually caused by out-of-balance
ing outer race will freeze in the spindle sleeve and the wave springs will no
s,
ulling wheel forward with fingers while watching indicator. When released, the needle should
o hard.
oading up or glazing of the wheel, particularly if grinding without coolant can cause chatter.
fter grade.
the taper in the wheel adaptor sleeve is not the same as that on the spindle nose, or if a piece of
per, a chatter can appear on the work. Check the adaptor
he super precision bearings used in the Harig® spindle are sized to give many years of service.
indle or motor bearings does occur, chatter will appear on the work
mic
the 3-phase current supplied to the machine is not reasonably uniform, a poor finish will result.
phase converter used to run a three-phase motor on a single-phase supply will also affect
use of the unbalanced current a converter delivers.
rer
d is rated to run
only a few millionths of an inch high, weigh the economics of the more frequent wheel dressing
against the slight loss of appearance.
E. Loss of preload.
O
wheels), the rear bear
longer hold the spindle shaft tightly back against the front bearings. To check for loss of
preload, place an indicator against the spindle nose. Push against wheel guard with thumb
p
instantly return to original position. If needle will return to original position only by rotating
wheel by hand, return spindle to factory for repair. Be sure to state that there was a loss of
preload on this test.
F. Grade of wheel to
L
Replace wheel with one of a so
G. Taper of adaptor sleeve in error.
If
dirt or grit has been assembled on the ta
sleeve by putting a thin film of Prussian blue inside the sleeve and press it on the spindle. The
spindle taper should show contact all around the circumference on two separate rings.
H. Ball bearing failure.
T
If a failure of either the sp
being ground, and a noise will be heard when the spindle is running. (Wheel, wheel nut and
washer should be removed to make certain an unbalanced wheel is not causing the noise.)
Replacement of all bearings on the spindle assembly, or a new motor, is required. It is
recommended that the spindle assembly be returned to the factory for repair so that the dyna
balance of the unit can be checked.
I. Unbalanced electric supply.
If
J. Use of phase converter.
A
finish and motor sound beca
The type of converter that switches out of the circuit after starting the motor will cause a poo
finish than a single-phase motor. The type of converter that stays connected, an
only the spindle motor, will give a better finish than a single-phase motor.
2. LONGITUDINAL LINES- SCRATCHY FINISH
A. Wheel is too soft for material being ground.
Grains in too soft a wheel pull out before they
ave really dulled. The dressed surface will be lost quickly and the few remaining pointed
wheel is not cutting freely, longitudinal lines in the finish, sometimes a discolored or burnt
l or pass the diamond across the wheel at a
faster speed when dressing. Do not dress the wheel without a down feed before each pass.
h
grains give a scratched appearance. Replace with a harder wheel.
B. Wheel dressed too finely, or wheel too hard.
If
finish will result. Replace with a softer grade whee