Special maintenance program for the atomizer wheel
The GEA Niro Certified Service Programme is a program that supplements the wheel inspections performed by on-site plant operators. The programme requires that the entire atomizer wheel is returned to a GEA Niro office for inspection, repair and spin test.
The service procedure begins with a careful inspection for possible degrading effects. Unless the wheel is considered to be unsafe or damaged beyond repair, the service also includes repair or replacement of damaged parts. The service procedure is concluded by balancing of the wheel parts as well as the assembled wheel.
Extra care
The atomizer wheel is a key component in a spray drying plant and, as such, GEA Niro strongly advise customers to use the GEA Niro Certified Service Programme as part of a preventive maintenance programme. As the atomizer wheel is rotated at high speed, it is consequently exposed to very high centrifugal forces and high levels of tensile stress. Experience over many years shows that spray drying plants equipped with rotary atomizers do not constitute any health and safety risk when carefully operated and maintained in accordance with operating and maintenance instructions and safe industrial practices.
However, in cases where insufficient attention has been paid to the maintenance of atomizer wheels and/or where non-original parts have been incorporated in GEA Niro atomizer wheels, dangerous incidents have occurred involving wheel fragmentation during spray dryer operation.
Atomizer Wheel disintegration can be caused by any one or a combination of the following:
- High temperature
- Stress corrosion cracking
- Wear or abrasion
- Material fatigue
- Other wheel damage.
Careful monitoring of the condition of atomizer wheels and regular maintenance is essential to prevent such dangerous incidents.
The GEA Niro atomizer wheel is designed to withstand the high level of tensile stress by precise mechanical design, emphasising avoidance of stress corrosion and securing an adequate cross-section of high strength material in all parts of the wheel. Careful material selection, which can withstand the influence of temperature, corrosion and wear during atomizer operation, is also carefully considered throughout the design process.
However, as the wheel is operating in an industrial environment, it is subject to degrading effects such as wear and corrosion, and therefore should be carefully monitored and maintained by its operator.
Operating and Maintenance Instructions
The safe operation of all GEA Niro equipment, including the atomizer wheel, depends on the operation and maintenance of the equipment in strict compliance with the operating and maintenance instructions provided in the manuals and any other training programme for the customer.
It is imperative that operators are aware of the following:
- Never run the atomizer wheel at speeds higher than those specified or recommended by GEA Niro.
- Never run the atomizer wheel when it might be only partially assembled, i.e. without upper plate or with loose bolts.
- Never attempt an atomizer wheel repair.
- Only use approved cleaning liquids for atomizer wheel cleaning, i.e. water, dilute organic acids and CIP liquids recommended for stainless steel surfaces. When in doubt, consult GEA Niro. Under no circumstances use liquids that contain chlorine.
- Only use original GEA Niro replacement parts.
Service Intervals
GEA Niro recommends that every atomizer wheel is submitted to GEA Niro at certain times in its operational life.
The recommended points in time are:
For stainless steel wheels containing wear resistant parts:
- 1st service: After 2 years of operational duty
- 2nd service: After 4 years of operational duty
- 3rd service: After 5 years of operational duty.
For stainless steel wheels containing no wear resistant parts:
- 1st service: After 5 years of operational duty
- 2nd service: After 8 years of operational duty
- 3rd service: After 10 years of operational duty.
Thereafter, service is recommended each year.
These are only guidelines and are not considered an extension of warranty. Any sign or suspicion of damage should be taken seriously.
In case of doubt about the condition of the wheel, the entire wheel should be returned to GEA Niro for a certified service inspection, repair, and spin test.