Increasing the Operability of Machinery for Thirty Years
POSITIV 3/2020 69
REGION
measurement station LEICA TDRA6000. We also relied
on our precision calculations, without which the results
might have been distorted,” describes Ing. Róbert
Púchy, responsible for measuring the generators in
Sweden.
“The thorough measuring detected a minor deformity
of the stator, however, the air gap between the stator
and rotor, and the rotor itself do not show significant
abnormalities,” adds Mr Púchy. After the service
performed by the Czech companies, both generators
of the Ängabäck power plant in Sweden can continue
working safely for many years to come.
Timely Detection of Defects Prevents Machinery
Breakdown
Many producers do not know exactly what the technical
condition of their machinery and production lines is.
Repairing broken-down machinery is often a costly
process. Repairs grow more expensive when loss
resulting from a temporary stop in production builds
up. dif operates systems which also monitor vibrations
and temperatures.
Monitoring vibrations reveals a minor defect in
a machinery part, typically damaged bearings and
worn-out gears, before it develops. Such damage is
usually revealed by increased vibrations. The level
of vibrations also shows whether the machinery is
balanced and stabilized properly. Monitoring bearing
running temperature indicates more serious problems:
when the temperature goes up, the machinery may be
hours or even minutes from a breakdown. Then prompt
action is necessary.
Production Lines in Škoda Plants Must Not Stop
The number of vehicles dispatched from the production
plants of Škoda Auto, a.s., is on the constant incline.
A great range of production processes is automated and
robotized. Production lines in such a busy operation
must never stop: the loss would be immense. In 2016,
the dif prepared a solution based on monitoring coating
shop conveyor bearings, and won the competition.
“Diagnostics of the low spin gear is a challenge. One
cycle of the wheel takes twenty-three seconds,” says Mr
Falc, head of the project. “I invited experts from B&R
to cooperate, as we had already done the project of
diagnostics of mining fans and extraction machinery
in OKD. This time our cooperation resulted in on-
line vibration diagnostics of the coating shop by the
Aprol ConMon programme, a short form of condition
monitoring.”
Investment Pay Back
366 vibration sensors (accelerometers) were installed
at the conveyors of the production lines in the first
stage of the project. A dedicated computer collects the
data. “Measurement is based on the fact that the initial
stage of a damage demonstrates through an increasing
energy of high frequency vibrations,” explains Mr Falc.
“This method is sensitive to insufficient greasing and the
seizure resistance of components. Most importantly,
we evaluate all diagnostic data in real time, in half-
second cycles.”
Investment aimed at the installation of the diagnostic
system in the coating shop has already paid for itself
because production capacities are growing. The
diagnostic system has contributed to that: 2,180 vehicles
had been produced before, while the daily production
since the beginning of 2019 has been 2,220 vehicles.
This is why this cooperation has been extended to cover
diagnostics projects with 220 technologic fans and lifts.
The current installations at Škoda sum up at a notable
1,668 sensors.