5. Page 5
Rotary kiln assembly
1 Rotary kiln shell 7 Guard for rack and pinion drive
2 Kiln inlet with inlet seal with lubrication device
3 Tires with fastening 8 Kiln drive
system 9 Kiln outlet with outlet seal
4 Supporting roller stations 10 Kiln hood
5 Kiln longitudinal guide 11 Clinkering zone cooling (optional)
6 Rack and pinion drive
6. Page 6
The POLRO 2 - support kiln
• splined tires (cold gap 0.4%)
• self-aligning rollers
• direct drive via supporting rollers
• pneumatically applied inlet and outlet seals
• air cooled kiln inlet tray
7. Page 7
Process - technological dimensions
Kiln with preheater
Kiln with calciner
10 12 14 15 17
L/D ratio
3 - Stations
Number of stations and L / D ratio
2 - Stations
10 12 14 17
L/D ratio
3 - Stations
Design of rotary kilns
8. Page 8
3 - support kiln versa 2 - support kiln
3-support kiln 2-support kiln
Statically undefined
• possibility of
- extreme overload
- plastic deformation
• requirement for
- etxra safety margin
- regular adjustment
Statically defined
• constant support loading
• elastic deformation only
• no sensitivity to misalignment
long enough for process?
22. Page 22
Description of the kiln shell calculation basics
The shell is a rotating drum made from rolled steel plates. These shell sections
have the same inside diameter but different plate thickness. All sections are
welded together.
The shell thickness is a result of some calculations, the so-called Kiln Static.
Basic for the kiln static are some mechanical rules and some limiting factors
for the shell material, the so-called Design Criteria.
The design criteria for a kiln shell is the Bending Stress.
Different kiln areas have different Loads.
23. Page 23
Functions of the kiln shell
• Conveys material
• Guides gas from cooler to kiln
• Creates a constant moving material bed
allows heat exchange between gas
and material
• Holds the brick lining
25. Page 25
Description and function of the kiln tire
The tire is a steel ring on the outside of kiln shell. It works as an
stiffener for the kiln shell. The kiln tires have to carry the kiln weight.
Functions: • Transfer load from shell to the rollers
• Keeps the shell in a round shape
• May transfer torque from roller to tire
Design criteria: • Tire bending stress
• Ovality in %
37. Page 37
Description and function of a kiln roller
A kiln roller is a steel wheel which is supported on each side.
Each tire is supported by two rollers.
Functions: • Transfer load from tires to base plate
• Supports tires and keeps them in position
• Can transfer torque from rollers to tire
• Allows rotation
Design criteria: • Hertz Pressure
• Bearing Pressure
38. Page 38
Roller station
1 Base frame
2 Bearing housing
assembly
3 Roller and shaft
assembly
5 Guide block
12 Oil level indicator
47. Page 47
Kiln hood
1 Lower part of hood
2 Upper part of hood
3 Suspension door
4 Trolley arrangement
5 Burner seal
6 Inspection port
7 Access door
8 Sub plate
9 Collar segment
10 Seal to cooler
11 Opening for measuring
socket
49. Page 49
Check points of kiln inlet seal:
• Slot between support ring and slide ring
• Thickness of the wear ring
• Visual check of sealing surfaces
• Check for material leakage
• Pre-tensioning of sealing robe
Maintenance kiln inlet
50. Page 50
Air pressure net:
• Air pressure for pneumatic-cylinder
• Check of water separator
• Check of lubricator of pressurized air
• Check for leakages
Maintenance kiln inlet
Air pressure system
51. Page 51
Check of outlet seal:
(similar to inlet seal), with additional points:
• Graphite lubrication of slide rings
• Function of pendling hatch
• Clearance of dust chute
• Functioning operation of expansion joints
Maintenance kiln outlet
52. Page 52
Check of splined tire fastening:
• Check of wedge pre-tension
• Visual check of tire area
• Check of welds
Maintenance splined tires
53. Page 53
Check of floating tire fastening:
• Control of relative movement
• Play measurements during stop times
• Control of axial retainers
• Lubrication of slide surfaces
• Check of welds
Maintenance floating tires
54. Page 54
Damages at base plates by defficient lubrication
Maintenance floating tires
57. Page 57
Maintenance / lubrication points
15 Kiln tire
16 Inlet seal
17 Oil atomizer for inlet seal
18 Oil atomizer for outlet seal
19 Cooling air fan
20 Fan for clinkering zone
cooling system
58. Page 58
Maintenance / lubrication points
21 Supporting roller
bearing station I
22 Supporting roller
bearing station II
23 Supporting roller
bearing staton III
24 Supporting roller
bearing station IV
25 Graphite lubrication
equipment
