Atlas centrifugal air compressor lubricant | Samsung centrifugal air compressor sensor

Atlas centrifugal air compressor lubricant | Several implementation methods of Samsung centrifugal air compressor sensor anti-surge automatic control system: Fixed limit flow method The anti-surge control system of fixed limit flow is to keep the flow rate of the compressor always greater than A certain flow rate to avoid operating in the surge zone. The advantage of this method is that the control system is simple and uses fewer instruments. The disadvantage is that when the compressor speed is reduced and the anti-surge control system is put into operation at low load, the return flow will be large and the energy consumption will be large. The variable limit flow method is used in situations where the compressor load may be changed by speed regulation. Because the limit surge flow rate is a variable under different speed conditions and becomes smaller as the speed decreases, the most reasonable anti-surge control method should be Leaving an appropriate safety margin allows the anti-surge regulator to work along a safety control line on the right side of the surge limit flow curve. This is the variable limit flow method. Through daily work summary, there are several ways to prevent and solve the surge phenomenon of the compressor: Find the surge point according to the compressor performance curve. For general industrial applications, the lowest allowable operating point can be used. Install a temperature and flow monitoring instrument at the inlet of the compressor and install a pressure monitoring instrument at the outlet to give an alarm in time if surge occurs. If it is necessary to reduce the flow rate of the compressor during production, a bypass loop can be set up at the compressor outlet to allow the gas to be vented or returned to the intake pipe after decompression. When operating at a small flow rate, the compressor speed can be reduced so that the compressor does not enter a surge state when the flow rate decreases. The outlet of the unit should be equipped with an anti-surge line. The set value can be set to the lowest allowable operating point. Once the unit inlet flow pressure drops to the minimum allowable operating point, the anti-surge line can be automatically opened to allow the outlet gas to flow back to the inlet. The reason for the formation of surge is the periodic alternation of reverse flow and air supply. The centrifugal compressor is connected to the pipeline network to form a closed gas medium transportation system. The compressor and the pipeline network work in this system at the same time, providing the necessary conditions for the transportation and pressure increase of the gas medium. If the flow rate of the compressor is constant during the transportation of the gas medium, Reduce When the compressor inlet flow rate is reduced to a certain value, the gas first generates a separated vortex flow in the impeller flow channel, further reducing the gas separation vortex area in the impeller flow channel and further expanding and forming a serious rotational detachment phenomenon. The gas flow state is seriously deteriorated and the compressor is discharged. When the pressure drops significantly, the pipe network gas will flow back to the compressor until the compressor outlet pressure is greater than the pipe network compressor and starts to discharge gas again. This periodic oscillation phenomenon produced by the air flow in the system is commonly known as compressor surge. That is to say, when the compressor flow rate is small enough, severe rotational stall will occur in the entire diffuser flow channel. The compressor outlet pressure suddenly drops, causing the pressure of the pipe network to be higher than the compressor outlet pressure, forcing the air flow to flow back to the compressor until it reaches the pipe. When the network pressure drops below the compressor outlet pressure, the compressor begins to supply air to the pipeline network again and the compressor returns to normal. When the pressure in the pipe network returns to the original pressure, the flow rate is still less than the surge flow. The compressor will produce a serious rotational stall and the outlet pressure will drop. The air flow in the pipe network will flow back to the compressor. This cycle causes periodic large fluctuations in the compressor flow rate and outlet pressure, causing strong air flow fluctuations in the compressor. This phenomenon is called compressor surge. Generally, if the pipeline network capacity is large, the surge amplitude will be large and the frequency will be low. On the contrary, if the pipeline network capacity is small, the surge amplitude will be small and the frequency will be high. The harm of surge phenomenon in centrifugal compressors The surge phenomenon of centrifugal compressors is extremely harmful to the compressor, mainly in the following aspects: ① During surge, the strong pulsation and periodic oscillation of the air flow will cause the air supply parameters to change. Large fluctuations (pressure flow, etc.) destroy the stability of the process system. ② The blades will vibrate strongly and the impeller stress will be greatly increased and the noise will be aggravated. The centrifugal air compressor has taken over the dominant position, but it still has a certain living space. It can be seen that it still has some unique and superior characteristics that other types of air compressors cannot completely surpass. Its advantages are: when the reciprocating air compressor adopts a high-strength design, the rotation speed is low, it is sturdy and durable, and the failure rate of continuous use is also very low. Noise pollution is also an important factor in environmental pollution. People living near factories or highways are more or less troubled by the noise from mechanical equipment and cars. The use of noise pollution indicators as indicators for assessing factories and living environments has long been included in the national environmental maintenance standards index.