During normal operation of roots blower, if the vibration value exceeds the specified technical requirements, specific analysis shall be carried out according to the vibration characteristics to determine the cause of vibration.
The causes of the vibration caused by the imbalance of roots blower impeller are: loose, changed, deformed parts on the impeller, or uneven corrosion and wear; Solid particles in the working medium are deposited on the rotor; The weight of new parts replaced during maintenance is uneven; Impeller material is not absolutely symmetrical during manufacturing; There are errors in machining accuracy and assembly deviation.
Vibration caused by electrical defects: the stator three-phase magnetic field is asymmetric, and the magnetic center is dislocated due to three-phase voltage imbalance, single-phase operation and other reasons; The stator core or stator coil is loose, which increases the electromagnetic vibration and noise of the stator; Electromagnetic vibration caused by uneven air gap of motor; Rotor conductor fault, loose parts, etc.
The vibration of roots blower can be roughly divided into the following types. During operation, roots blower resonates with the motor, and the vibration frequency is the same as the speed, which is mainly the result of unbalanced rotor mass. As the rotor mass is unbalanced, it will be impacted by the centrifugal force generated by the unbalance every revolution. Vibration is the result of such centrifugal impact, or the bending of the shaft.
Design reason: Roots blower is generally designed according to the operating environment, temperature, air volume, air pressure, medium, etc. of the fan, while some enterprises do not select the type completely according to these factors, resulting in the following factors: improper fan design, poor dynamic characteristics, and vibration during operation; Unreasonable structure and stress concentration; The design working speed is close to or falls into the critical speed zone; Inaccurate calculation of thermal expansion leads to poor thermal alignment.
2. Manufacturing reason: the fan manufacturer's quality requirements for the fan also affect the operation of the fan, such as poor processing and manufacturing of parts and insufficient precision; Poor material, insufficient strength and manufacturing defects of parts; The rotor dynamic balance does not meet the technical requirements.
Reason for installation and maintenance: the installation accuracy of roots blower plays a vital role in the operation of the blower. If the installation accuracy does not meet the installation requirements, it will damage the operation of roots blower. In the process of fan installation, there are the following influencing factors, such as improper mechanical installation, misplaced parts, and large preload; Poor shaft alignment; The fit clearance, interference amount and relative position of the machine are adjusted improperly; The rotor is improperly placed for a long time, which changes the dynamic balance accuracy; The original matching property and precision of the machine were damaged due to the failure to carry out maintenance according to regulations.
Operation reason: during the use of roots blower, the quality of fan maintenance plays a decisive role in the operation quality of roots blower. For example, the process parameters deviate from the design values, and the machine operation condition is abnormal; The operation of the machine at over speed and over load has changed the working characteristics of the machine; Poor lubrication or cooling; Partial damage or scaling of rotor; Inappropriate operation during startup and shutdown or speed increase and decrease, uneven thermal expansion or too long stay in critical area.
Reasons for machine deterioration: general equipment has a certain number of years in use, and equipment performance will deteriorate after reaching a certain number of years. The same is true for Roots blower. For long-term operation, rotor deflection increases or dynamic balance deteriorates; The rotor is partially damaged, fallen off or cracked; Wear, pitting or corrosion of parts; The force on the mating surface deteriorates, resulting in insufficient interference or looseness, which destroys the mating property and precision; The machine foundation settlement is uneven, and the machine shell is deformed.
I believe that after reading the above content, you should also understand why Roots blower produces vibration. I hope it will help you.
Text term label: Roots blower
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