Vibration Analysis Of Centrifugal Fans

Vibration Analysis of Centrifugal Fans: Ultimate Guide from Ocean

Industrial systems and their corresponding processes need to take care of critical assets or machinery, which involves specialized monitoring of their operating conditions.

Centrifugal fan is a simple machine but can cause many operational and mechanical failures which need analysis of various factors such as working speed, gas flow, vibration and temperature levels, noise levels, load, etc.

Vibration analysis refers to a condition monitoring test used to determine the operating conditions of equipment, here, the centrifugal fans. In this blog, let’s walk through the vibration analysis of centrifugal fans and their processes in detail.

Read more about:

  1. Cloud-based Vibration Monitoring
  2. IoT Condition Monitoring Methods
  3. What Is Reliability Centered Maintenance? A Simple Guide

Vibration Analysis Fundamentals

Before discussing the vibration analysis, let’s consider the major causes of fan vibration:

1. Shaft Misalignment

During installation, the motor shaft and the fan shaft need to be aligned appropriately. The misalignment can cause additional axle and harmonic vibrations.

It also occurs with the lack of proper seating of bearings or bent shafts. Before starting the equipment, the use of laser alignment tools analyzes whether the alignment is appropriate or not.

The symptoms can persist if the system isn’t able to detect the bent shaft.

2. Resonance

If a new fan operates beyond the critical speed, you need to track the vibration levels. When vibration excessively passes through critical speeds, it results in the damage of bearings, seals, and related equipment.

Once the fan functions at an optimal resonance point with no corrections, this can cause parts failure. The residents change based on the operating speed and use various tools and technologies for detection.

3. Loose connection

When the mechanical connection between the caps or bearing pedestals goes untightened, it produces excessive vibrations.

Misalignment is another common failure in centrifugal fans that occur due to inadequate alignment and tolerances, weakness in the supporting base, distortion in the motor base, coupling damage, pulley and belt damage, excessive runouts, etc.

4. Bearing problems

Bearing issues occur usually due to the following concerns like lubrication problems, deterioration of parts, wrong component assembly, excessive misalignment and collateral damage, life span wear, etc.

Vibration Analysis Of Centrifugal Fans


Steps involved in the vibration analysis of centrifugal fan

Vibration analysis is a kind of predictive technology that can analyze unbalance in the machinery with the help of an accelerometer.

It utilizes a voltage signal similar to the extent of vibration, the machine emits and its frequency. We can also figure out the time per second the vibration occurs.

The information goes for further analysis and the trade analyst conducts the diagnosis of the machine.

Initially, you need to mount and prep the centrifugal fan vibration analysis before you analyze it.

The fan is laid on a flexible base or supported installation.

The natural frequency should read beyond the running speed. With the accelerator record the vibrations per direction in axial vertical and horizontal directions.

It records two kinds of vibrations, namely filter-in and filter-out. The filter-in vibration reading detects the vibration only at a single frequency whereas the filter-out vibration analyzes vibration for a range of frequencies.

The vibrational analysis also sorts out the velocity and amplitude testing. Velocity measurement analyzes the extent of vibration, while amplitude considers the possibilities of fatigue damage.

Maintenance and repair of centrifugal fans


Role of timely fan maintenance in eliminating catastrophic failures

The timely maintenance of centrifugal fans helps with the following:

  • Inspection of foundation bolts to understand the condition of bearings
  • Analyze the dynamic condition of the fan group
  • Know the origin of the problem through analysis of the operation and maintenance log
  • Understanding the situation to implement optimal remedial process
  • Evaluating the collateral damage for various components.

Common practices in centrifugal fan maintenance

1. Balancing

Implementing the balancing technique works best when you put it right to the complete assembly of fans. It needs full speed and trim balancing, which helps you ensure fan performance, maintenance, and safety.

2. Alignment

Mechanical equipment cannot prevent errors while installing, which is the same case for centrifugal fans. While installing couplings, there occur deviations in the motor and main fan shafts. Alignment helps in mitigating these deviations to maintain the harmonic rhythm of the equipment.

3. Bolt tightening

The tightening of bolts avoids the consequences of structural issues. Once the fans undergo structural problems, bolt tightening with specified torque can help with the proper equipment alignment.

Also, lubrication of the centrifugal fans needs to fulfill certain requirements. Since oil analysis helps with analyzing the service life of the fans. While adding the lubricating oil, it should go well with the bearing type, load size, operating speed, and the operation ecosystem chosen.

Repair techniques for the damaged centrifugal fans

  • Welding

As a part of the repair process, you need to consider eliminating the worn materials and excavating wear-resistant deposits or existing welds.

The removal of wear plates is significant in preparing the roughened surfaces reasonably well to make the welding desirable.

  • Grinding 

The fan system plays an integral role in the success of dust, air, gas, or material handling applications. Once they degrade or affect damage, they can cause plan operations to halt.

The grinding process reduces repeatability and avoids the mental burden of operators thereby effectively helping the machine maintenance.

  • Replacement of worn-out parts

The fans are used in various applications and they can be subjected to an abrasive atmosphere. The wearing surfaces of fans need replacement after using them for quite a long time.

Wearing services should consider the following factors: they should be quantified, found, and should have an estimate of the remaining lifespan of the wearing surface.

The repairs and their nature needs to be framed according to the above factors and a plan has to be implemented to replace the damaged parts.


Digital Ultrasonic Testing Device for Preventive Maintenance

In the era of Industry 4.0, the importance of optimizing processes, enhancing operational safety, and improving energy efficiency continues to grow. To tackle the challenges of Maintenance 4.0, SONOTEC introduces the cutting-edge SONAPHONE—a digital ultrasonic testing device that integrates advanced sensors and user-friendly software for preventive maintenance. This innovative solution facilitates intuitive operation and opens up new avenues for implementing processes in various applications.

Vibration Analysis of Centrifugal Fans with Oceanme

There are acceptable vibration levels for the fans running at various speeds—- the vibrations have a particular sound and they produce unique linear patterns. This pattern disrupts once the fan gets damaged.

At Ocean, our experts detect the root causes like misalignment, imbalance, bearing concerns, etc., and provide services to fix them. In case of taking urgent action against these concerns, we take recommendations or else provide the scheduled maintenance services to the clients.

Ocean takes all measures of providing services safely to conduct vibration analysis and condition monitoring of centrifugal fans and other rotating equipment to make sure they work without disruption.

To get further details on vibration analysis services and condition monitoring services from Ocean, contact us today.

Share on facebook
Share on twitter
Share on linkedin