|Rotary kiln axis hot alignment.|
The importance of hot alignment:
A kiln’s axis misalignment, both, vertically and horizontally, has a direct impact on the life of the refractory causing refractory failure (breaks and falls), and, because of this, the kiln’s shell can be exposed to excessive heat which can cause permanent deformation, and even breakage due to stress and fatigue.
This generates overload at piers and rollers (producing heat and stress on rollers bearings, deformations in the contact surfaces of tires and rollers).
Girth gear and pinion misalignment produces meshing interferences, irregular wear on gear drive and pinion gear and, consequently, higher energy consumption.
It also causes problems in kiln seals.
These problems are due to multiple causes, such as construction errors, foundation and movement of settlements, movement of rollers, wear on tires of rollers, wear or deformation of roller bearings. This is the reason why it is advisable to perform this measurement at least once every 3 years.
The laser alignment method includes a group of measurements planned to determine the kiln’s vertical and horizontal center positions at every pier. Depending on the results, we calculate the rollers movements to achieve the axis alignment.
The alignment can also be done with cold kilns and, in order to do so, the production has to be stopped and should be done during scheduled shutdowns. It is advisable to do it once a year.
Finally, we offer our services to supervise the rollers movements to align kiln’s axis.
This measurement is our main and most complete service, since it includes a set of measurements, which allows a full diagnosis of the kiln’s problems. However, these measurements can be made separately, according to the particular needs of each plant.
· Measurement of vertical and horizontal position of the center of the kiln at every support.
· Measurement of spatial position of roller shafts (skew, slope, and functioning angle).
· Tires and rollers profile measurement.
· Roller Shaft bending measurement.
· Measurement of kiln’s shell ovality (Shell test), and tires migration.
· Measurement of kiln’s shell external topography.
· Tire wobbling measurement.
· General inspection of kiln, rollers, tires, seals and drive gear.
· Girth gear run out and wobbling measurements.
· Temperature profile of girth gear and pinion’s teeth, to identify symptoms of misalignment.
All these measurements are taken into account to recommend the most suitable actions to be taken for improving the equipment’s performance.