Contact Us
TEL: +8615381220188
Fax: +86-573-84133388
E-mail: doris@mechanicalseal.com.cn
Address: No. 1168 Jinyang Road, Luoxing Street, Jiashan County, Jiaxing, Zhejiang, China
Home > Knowledge > Content
Mechanical seal flushing program and features
May 28, 2018

Mechanical seal flushing program and features


The purpose of flushing is to prevent accumulation of impurities, prevent the formation of air bags, maintain and improve lubrication, etc. When the temperature of the flushing liquid is low, it also has a cooling effect. The main methods of flushing are as follows:

First, flush

1 . Positive flush

(1) Features: The sealed medium of the working host is used, and the outlet end of the pump is introduced into the sealed cavity through the pipeline.

(2) Application: For cleaning fluids, p1 is slightly larger than p. When the temperature is high or there is impurities, coolers, filters, etc. can be set on the piping.

2 . Backwash

(1)Features: The sealed medium of the main engine is used. The pump's outlet end is introduced into the sealed chamber. After flushing, it flows back to the pump inlet through the pipe.

(2) Application: For cleaning the fluid, and p 3 . Full flush

(1) Features: The sealed medium of the main unit is used. The pump's outlet end is introduced into the sealed chamber through the pipeline. After flushing, it flows back to the pump inlet through the pipeline.

(2) Application: The cooling effect is better than the first two, used for cleaning the fluid, and p1 is close to the p-in and p-out.


Second, outside the rinse

Features: Introduce cleaning fluid that is compatible with the external system and the sealed medium to the sealed chamber for flushing.

Application: The external flushing fluid pressure should be 0.05--0.1MPa larger than the sealed medium. It is suitable for applications where the medium is high temperature or solid particles.


The flow rate of the rinsing liquid should ensure that the heat is removed, and the need for rinsing needs to be met without causing erosion of the seal. For this purpose, the pressure in the sealing chamber and the flushing flow rate need to be controlled. Generally, the flow rate of the cleaning flushing fluid should be less than 5 m/s; the slurry liquid containing particles should be less than 3 m/s, in order to achieve the above flow rate value, the flushing liquid and the sealing chamber The difference in pressure should be <0.5 MPa, generally 0.05--0.1 MPa, and 0.1--0.2 MPa for double-end mechanical seals.


The position of the rinsing liquid entering and exiting the orifice of the sealing chamber should be set near the sealing end face, and should be near the moving ring side, in order to prevent the graphite ring from being eroded or due to uneven cooling caused by temperature difference deformation, as well as impurity accumulation and coking, etc. Tangential introduction or multi-point flushing can be used.


If necessary, the rinse solution can be hot water or steam.



Contact us:


Susie Ding

Email: susie@jxburgmann.com

Skype: susiecc0523





Previous: What is the knowledge and application of mechanical seal selection?

Next: What are the external factors of the mechanical seal sealing effect?