One of the main requirement of rotary drums proper operating is an assurance of
adequate forces' distribution in their support systems.
Unfortunately, this aim is not always possible to achieve. One of the obstacle is
shape errors of roller raceway such as conicity, saddleback distortion or characteristic
edges, which take place even with correct rollers' position parameters. They make
that the assurance of rotary drum's mechanical stability is impossible, being a
boundary of its free axial motion.
In the past, and at present, the error roller's replacement with the new one with
cylindrical shape is the antidote to this state.
But this is the economic groundless activity (dis- and assembly expenses, transport
and machining expenses), and besides, it forces the plant to stop.
The need of the new solution of this important problem appeared.
Going to satisfy this demand, our firm took on the activity leading to study and
create device to large dimensions and weights rotary parts' resurfacing during their
The attempts of rotary parts regeneration during their operation were performed
for many years, but the imperfection of past control and power transmission systems
and the gap in metrology assortment's field, manifesting as the lack of precision
positioning systems and the lack of the big diameter measuring devices in the operation
conditions, destined this method to fail.
But taking advantages of the processing way into consideration, the temptation to
improve was significant. So, in the first quarter of 1995, after one year of experiments,
we managed to outline final machine tool concept.
Simultaneously we made the project of precision device to large diameter's measurement
during rotation, with 0.1 mm accuracy.
This device, operating on circumference measurement principle, arised in 1996 and
has been tested during many of rotary drum inspections.
Soon, we could offer, with a big satisfaction, to our clients usage of full numerical
moveable machine tool.
For the first time, the machine was used during complex rollers of lime kiln no 1 regeneration in KUJAWY S.A. (LAFARGE) in October 1996.
Work on this plant (3 piers) has lasted for 16 days (24 hours per day). No disruption
appeared and new cylindrical rollers' raceways restored the proper operation's conditions
of support system's rotary elements.
Since that moment, roller regeneration has been the constant position of our company's
- no necessity of expensive and laborious dis- and mantling. Avoiding of these actions
lets us in simply way save time and people's effort. Besides, this makes, that no
heavy equipment such as cranes, jacks etc. are needed,
- elimination of expensive transportation to and from regeneration place. Parts, to
which the method is destined, are generally large and heavyweight. Regeneration
of them requires massive stationary machine tools, but they are only in few machine-shops,
- possibility of process continuity assurance. More than once, especially in seasonal
lines, there are priorities, which force to uninterrupted plant's operating. It
is difficult to reconcile these non drum stoppage's requirements with replacement
of its parts. In the case mentioned above this method seems to be irreplaceable, making possible
combination of regeneration with full plant operating,
- basing on real rotary axis during regeneration. Such machining datum assures the
more proper part's work during its normal usage. Wrong established rotary axis on
stationary device is often the cause of work's disruptions after part mantling on
- rotary drums rollers' regeneration during their normal operation,
- regeneration of other large dimensions rotary parts.
Technology of resurfacing by turning has been replaced by the technology of grinding.