Page 25 - June

METALWORKING EQUIPMENT AND TOOLS

chief mechanic's departments at our machine-building enterprises, that is, specifically those
who directly have to control the technical state of any mechanism (unit) consisting of registered
with OGM. In addition, if the reason was not this, then any more or less competent mechanic
at the enterprise would easily make an accurate diagnosis of an excessively lumbering and
vibrating industrial vacuum cleaner.
In factories where industrial vacuum cleaners are manufactured (assembled), drive
motors are not produced. They are supplied from another manufacturer, who (according to
technology) is simply obliged to test their finished products. Therefore, a rotor-shaft-shaft of
a new electric motor, poorly installed in the stator
а housing, would immediately show its inconsistency
with the technical parameters, which exclude any
imbalance relative to the stator. Thus, an enterprise
that manufactures (collects) the finished product
(industrial vacuum cleaners) receives from its
subcontractor electric motors, already checked
and accepted by the manufacturer's quality control
department. It remains only to install and fix the
impeller with "blades" on the shaft-rotor of the
electric motor. Again, according to the technology,
the fan impeller after manufacturing is subjected to
static balancing and the imbalance is eliminated by
milling, that is, by the method of removing metal
in its individual sectors. Further, the ventilation
unit (industrial vacuum cleaner) is completely
b
б assembled and in finished form is subjected to a
factory test.
The test result is usually positive. New,
correctly installed bearings on the shaft-rotor of
the electric motor also have that not wasted margin
of safety, which allows the impeller, mounted on
the shaft, to maintain a stable geometry at high
speeds of its rotation. Then the finished product is
sent to the consumer.
What is the fate of these industrial vacuum
cleaners in industrial conditions we already know.
They regularly catch abrasive dust in production
facilities from working sharpeners. They work for a
year, two ... five years, until external negative signs
begin to manifest themselves: excessive noise and
Fig. 2. Shaft bending due to imbalance of the wheels: a) vibration. Only then will the OGM specialists begin
statistical b) dynamic
to find out the reasons for the noisy operation of an

Stanochniy park 25