Mechanical seal manufacturer Flushing scheme

The flushing of mechanical seal is an effective measure to control the temperature of mechanical seal and extend the service life of mechanical seal. The purpose of flushing is to take away heat, maintain and improve lubrication, prevent liquid film gasification, prevent impurity accumulation, prevent the formation of air bags, etc.

According to the type of flushing, it can be divided into internal flushing and external flushing. The internal flushing is carried out by using the transmission medium, while the external flushing is carried out by introducing external substances.  

Internal flushing and positive flushing

Working principle: the sealing medium is led into the sealing chamber by the outlet end of the pump through the pipeline.

Scope of application: it is used to clean the medium. p1 is slightly larger than p inlet. If the medium temperature is high or there are impurities, it is necessary to set coolers, filters and other equipment on the pipeline to deal with the medium.   

Backwash

Working principle: the sealed medium of the working host is introduced into the sealing chamber from the outlet end of the pump, and flows back to the pump inlet through the pipeline after flushing.

Scope of application: it is used to clean the medium, and p inlet<P1<P outlet. When the temperature is high or there are impurities, cooler, filter and other equipment can be set on the pipeline to treat the medium.    

Full flush

Working principle: the sealed medium of the working host is introduced into the sealing chamber through the pipeline from the outlet end of the pump, and then flows back to the pump inlet through the pipeline after flushing.

Scope of application: it is used for cleaning media, and p1 is close to the p-inlet and p-outlet, and the cooling effect is better than the first two

External flushing

Working principle: introduce the cleaning fluid of the external system to the seal chamber to flush the mechanical seal.

Scope of application: The pressure of external flushing solution shall be 0.05 - 0.1 MPa higher than that of the sealed medium, which is applicable to high-temperature medium or solid particles. The flow of flushing fluid shall not only ensure the cooling effect, but also properly control the flow,

Avoid unnecessary erosion of seals caused by excessive flow and shorten their service life. Therefore, it is necessary to control the pressure of the seal chamber and the flow rate of flushing. Generally, the flow rate of cleaning flushing fluid should be less than

The flow rate of liquid flushing fluid containing particles shall be less than 3m/s. In order to meet the above flow rate, the pressure difference between flushing fluid and sealing chamber shall be less than 0.5MPa, generally 0.05-0.1MPa,

For double face mechanical seal, 0.1-0.2MP can be used. The inlet and outlet of flushing fluid shall be set close to the rotating ring side and slightly close to the sealing face. Flushing fluid can be introduced tangentially or washed at multiple points,

To avoid the mechanical seal being eroded or deformed due to uneven cooling. In special cases, hot water or steam can be used as flushing fluid.