Maintenance Of Centrifugal Fans
                     Maintenance Of Centrifugal Fans
Neel Rao
Writes on industrial fan manufacturers & Reitzindia
 industrial fan manufacturers.
Like any other piece of industrial machinery that undergoes rigorous use and plays 
an important role, centrifugal fans need to be inspected regularly. Particularly, the 
fan surfaces and the impeller tend to collect deposits which reduce the efficiency of 
the fan and often result in vibration and imbalance.
However, it is to be kept in mind that only the minimally necessary amount of 
cleaning should be carried out and it should be done very carefully. Any harshness in 
the cleaning process may damage the airflow surfaces and surface finish. The type of 
cleaning would depend on the current situation of the fan and how rigorously it is 
used.
Warning: The electrical supply must be completely shut off and the lockout 
procedures followed before initiating the process. To prevent the wheel from 
rotating by any means, the rotating assembly should be blocked too.
Inspection
When a new centrifugal fan is installed, it should be inspected every few hours. The 
frequency of inspection can be gradually reduced in the order of daily, weekly, bi-
weekly, and then monthly.
Visual Inspection Of The Fan
It is essential to take a detailed look for any signs of damage to the fan blades or 
structural deterioration. In industries where the fans are run continuously, these 
inspections are usually made annually. However, if even an annual inspection isn’t 
possible, it is necessary to carry out maintenance inspections during any short 
shutdown.
Inspection Of The Fan Motors
One of the most visible signs of motor failure is unexpectedly low. However, low 
amperage might also indicate the fan assembly requires maintenance. Other than 
these, you might also want to check if the motor is running in the right direction and 
ensure that the condenser fan isn’t cycling too rapidly.
Cleaning The Fan Blades
The fan would become less efficient if the blades of the impeller get dirt-coated. 
Usually, effective filtration systems can keep out most of the dirt. However, it is still 
wise to carry out at least one inspection every year. As the blades of the impeller in 
the forward curved fans are scoop-shaped, they particularly tend to collect dirt. Even 
if it is a small fan, cleaning the blades might require about an hour as the impeller 
need to be taken off.
Lubricating The Bearings
The sleeve bearings must be lubricated twice or thrice a year as they are metal-to-
metal running surfaces. The bearings should be labeled with the recommended 
lubricant type and the lubrication intervals. You might want to keep in mind that the 
bearings cannot be re-greased. In case if a bearing generates excessive heat, noise, 
and vibration, it is likely to fail soon. This usually happens when the bearings get 
several years old and when it does, the bearing cassette needs to be replaced.
Adjusting The Belts
The belts in the centrifugal fans need to be protected from dripping oil, chemicals, 
and oil mist. If the belts aren’t protected and are constantly exposed to oil and 
chemicals or aren’t adjusted properly, they tend to wear out and need replacements 
more often than usual. If the belts are too tight, they would pressurize the fan shaft 
bearings and the motor excessively. This may cause either the belt or the bearing to 
fail. Loose belts wear out easily and cause the fan to lose torque by slipping off.
About REITZINDIA
Reitz India has set a benchmark to deliver high quality fans for heavy duty industries 
which can work at precise operating conditions like high temperatures and pressures. 
Reitz offer idealistic Centrifugal Fan and Centrifugal blower design that can be used in 
all large scale process industries like cement, iron & steel, power plants, fertilizers/ 
chemicals and more.
Thank you for spending your precious time in reading this article!