Analysis on the Common Failures of Centrifugal Air Compressor in Cigarette Factory

1. Overview of Centrifugal Air Compressor for Cigarette Factory

1.1 Centrifugal Air Compressor for Cigarette Factory

Centrifugal air compressor compress air at atmospheric pressure until the air pressure reaches a certain pressure value, at which point the compressed air provides power. It mainly consists of two main parts, namely, rotor and stator, in which the rotor contains the rotor shaft and components such as impeller, balancing disk, shaft sleeve, thrust disk, connecting joints and so on, which are fixed on the shaft. The stator, on the other hand, mainly consists of the cylinder, various types of spacers positioned on the cylinder block, bearings and other components.

1.2 Principle of Operation of Centrifugal Air Compressor in Cigarette Factory

The driving force for centrifugal air compressor work comes from the electric motor or industrial turbine. When the centrifugal air compressor is driven by the driving force, it will drive the impeller to rotate rapidly and pass through the impeller to realize the work done with the working gas in the impeller channel. Under centrifugal force, the working gas will enter the diffuser at high speed. When the working gas enters the diffuser channel, it increases the cross-section of the diffuser channel and successfully converts the kinetic energy of the working gas into pressure energy as a way to increase the pressure. Secondly, under centrifugal force, a gas-thinning region is created in the middle of the impeller, which pushes the working gas continuously from the inlet of the compressor into the impeller channel, assisting other continuous movements in the compressor. If the pressure ratio obtained from a single-stage impeller does not meet the requirements, it is possible to meet the high pressure ratio requirements by gradually increasing the pressure in series with the help of multi-stage impellers.

1.3 Process of Cigarette Production by Centrifugal Air Compressor

There is a production flow of cigarettes by centrifugal air compressor as shown in Figure 1.

2. Analysis on the Common Failures of Centrifugal Air Compressor in Cigarette Factory

2.1 Wheezing faults

Surge is a relatively common and most harmful failure of centrifugal compressors in cigarette factories during operation. When the centrifugal air compressor has wheezing, the motor, voltmeter, inlet and outlet pipelines outside the air end will be affected, and all the operating instruments on the control panel will swing drastically. In addition, wheezing will also damage the sealing system and bearing system of centrifugal air compressor.

2.2 Bearing Faults

The causes of centrifugal air compressor bearing failures mainly include the following four points: first, the lubrication parts inside the air compressor have problems, which increase the bearing resistance and cause failures. The second is that the bearing pitch of the air compressor does not meet its working requirements, resulting in increased friction of the bearings and the occurrence of failures. The third is that when installing the centrifugal air compressor, failures are caused by the unbalanced installation or the imbalance of its internal bearer. The fourth is that the centrifugal air compressor is installed asymmetrically, which causes failures.

2.3 Rotor Balance Faults

In the daily maintenance of centrifugal air compressor, when we are checking the rotor, we are prone to ignore the rotor balance problem, which leads to failures of centrifugal air compressor in the process of operation due to rotor imbalance, and the rotor balance failure will also cause components to loosen.

2.4 Sealing System Faults

Currently, the sealing system fault is also a type of fault that is relatively common in the operation of centrifugal air compressors, and this fault is mainly due to the asymmetry of the air compressor installation, unstable oil pressure, and dirt in the oil.

3. Common Solutions to Centrifugal Air Compressor Faults in Cigarette Factory

3.1 The Solution Measures for Wheezing Faults

Surge is mainly caused by problems with the frequency and internal connections of the parts, so it is important to follow the drawings strictly when installing centrifugal air compressors. In addition, before connecting we should also carry out the corresponding frequency calculation, mainly to determine the center of the parts, thus ensuring that the air compressor and its transmission line can be consistent, so as to avoid strong vibration problems due to low frequency and large amplitude, which may cause damage to the machine, and even personnel injury. In addition to this, it is particularly important to prevent excessive water content in the earth’s crust, especially in rainy weather, because if the earth’s crust contains too much water, it can cause the machine to become unstable and vibrate.

3.2 Resolution of Bearing Faults

When it is determined that the bearing of the compressor has failed, the relevant personnel should take appropriate methods to address the specific causes of the bearing failure. For example, for bearing faults caused by improper lubrication, it is necessary to replace the lubricant in time, and regularly check the quality of the air compressor lubricant to ensure that the lubricant does not contain water and dirt and other substances, so as to ensure that the bearing lubrication effect is good. For bearing faults caused by compressor clearance problems, maintenance personnel need to adjust the pitch of the bearings or replace the bearings. If the air compressor rotor assembly and couplings fail, you need to check whether there is dirt on the rotor assembly, or whether the rotor is broken, etc., if you find that there is dirt, you should remove it immediately and adjust the balance of the rotor, and if the rotor is broken, it must be replaced in time.

3.3 Countermeasures for Resolving Rotor Balance Faults

During the operation of a centrifugal compressor, if there is a problem with the rotor balance, it will affect the normal operation of the unit and cause great damage to the equipment. Once a fault occurs in cigarette production, it will affect production safety and product quality, so once it is determined that there is a fault in the rotor balance, it is necessary to take appropriate measures to deal with it immediately. Before using a centrifugal air compressor, the staff should adjust the balance and check whether the centrifugal air compressor’s rotor, rotor shaft and other parts are connected to each other safely and reasonably. Before formally proceeding with cigarette production, we also need to carry out simulation tests to obtain relevant data on centrifugal air compressor production to ensure its safety in operation.

3.4 Countermeasures for Sealing System Faults

When a fault occurs in the sealing system, the staff need to take appropriate treatment countermeasures according to the cause of the fault. For example: when the air pressure, oil differential system work fails, we can adjust the pressure to the prescribed range, and check the work of the differential pressure system and components, combine with the overall situation of the centrifugal air compressor operation to adjust. For sealing system faults caused by wear and destruction in the sealing section, the maintenance personnel need to remove and replace the broken sealing components timely.

4. Conclusion

Centrifugal air compressors are able to process natural air into compressed air by cooling and drying it under the action of electric energy, and currently air compressors have been widely used in chemical production. As a necessary mechanical equipment in cigarette production, once the air compressor has a fault in operation, it will affect the normal production of the whole cigarette production. Therefore, in order to reduce the number of compressor faults, the relevant personnel should attach great importance to its maintenance, once found that the centrifugal compressor fails, we should quickly find the part where the fault is located and the reasons for the failure, and take the corresponding solution to ensure that the normal operation of centrifugal air compressors.