Talking about Causes of Fan Vibration, Failure Factors and Treatment Methods

Analysis of the phenomenon of failure and the reasons there are rules to follow, in general there are the following:

 

 

■ □ Design reasons: The design is generally based on the use of the environment, temperature, air volume, wind pressure, medium, etc. to design, and some companies did not fully select these types of factors, resulting in the following factors: improper design, Poor dynamic performance, vibration during operation; irrational structure, stress concentration; design work speed close to or fall into the critical speed zone; thermal expansion volume calculation is not accurate, resulting in poor thermal centering and so on.

■ □ Manufacturing reasons: The quality requirements of the manufacturer also affect the operation, such as: poor parts processing and manufacturing, the accuracy is not enough; parts of poor material, strength is not enough, manufacturing defects; rotor dynamic balance does not meet the technical requirements.

■ □ Installation and Maintenance Reasons: The installation accuracy requirements play a vital role in the operation. If the installation accuracy does not meet the installation requirements, it will have a destructive effect on the operation. In the installation process, there are the following influencing factors, such as: improper mechanical installation, misalignment of components, large preload, poor shaft alignment, improper adjustment of machine geometry parameters (such as clearance, interference, and relative position); Improper positioning for a long time has changed the accuracy of dynamic balance; failure to follow the maintenance procedures has destroyed the original coordination properties and accuracy of the machine.

■ □ operation and operation reasons: in the use of the process, the quality of maintenance, maintenance, play a decisive role in the quality of the operation. Such as: process parameters (such as the temperature of the medium, pressure, flow, load, etc.) deviate from the design value, the machine operating conditions are not normal; the machine is running at ultra-speed, overload, changing the machine's operating characteristics; lubrication or cooling is bad; The rotor is partially damaged or fouled; the start-up or shut-down or the speed-up/down process is not operated properly, the thermal expansion is not uniform, or the residence time in the critical zone is too long.

■□ Cause of machine degradation: General equipment has a certain number of years when it is used, and the equipment performance will deteriorate if it reaches a certain number of years. For example, in the long-term operation, the rotor deflection increases or the dynamic balance deteriorates; the rotor is partially damaged, shed, or cracks occur; parts wear, pitting or corrosion, etc.; the mating surface is degraded, resulting in insufficient interference or Loosening, etc., destroys the nature and accuracy of the fit; the foundation of the machine is unevenly set and the machine casing is deformed.