Español
Pусский
As a mechanical seal auxiliary system, the pumping ring circulation method has been widely used in mechanical seals.
1.Classification of pumping rings
Commonly used pumping rings have two structures: centrifugal and spiral (see the figure below).Centrifugal pumping rings have open groove type, inclined hole type and semicircular groove type (see the figure below). The inclined hole type is designed to increase the flow rate of sealing liquid and reduce fluid resistance, and has requirements for the direction of rotation of the shaft. The spiral type has internal and external spiral fit and only external thread rotation (see the figure below). The latter is more commonly used. The threaded pumping ring has thread rotation requirements, which need to be paid attention to.
Commonly used pumping rings have two structures: centrifugal and spiral (see the figure below).Centrifugal pumping rings have open groove type, inclined hole type and semicircular groove type (see the figure below). The inclined hole type is designed to increase the flow rate of sealing liquid and reduce fluid resistance, and has requirements for the direction of rotation of the shaft. The spiral type has internal and external spiral fit and only external thread rotation (see the figure below). The latter is more commonly used. The threaded pumping ring has thread rotation requirements, which need to be paid attention to.
2.Working mechanism of pumping ring
The centrifugal pumping ring is to process the liquid outlet groove (or hole) on one side of the metal ring, and use the centrifugal force generated when the pumping ring rotates at high speed to throw out the sealing liquid in the liquid outlet groove (or hole), so that the sealing liquid on the outside of the pumping ring forms a certain pressure, divert out the sealing liquid on the outside of the pumping ring, and at the same time, the sealing liquid on the inside of the pumping ring is continuously replenished into the liquid outlet groove (or hole), forming a continuous pumping effect.The whole working condition of this mechanical seals auxiliary system is similar to that of a centrifugal pump.
The centrifugal pumping ring is to process the liquid outlet groove (or hole) on one side of the metal ring, and use the centrifugal force generated when the pumping ring rotates at high speed to throw out the sealing liquid in the liquid outlet groove (or hole), so that the sealing liquid on the outside of the pumping ring forms a certain pressure, divert out the sealing liquid on the outside of the pumping ring, and at the same time, the sealing liquid on the inside of the pumping ring is continuously replenished into the liquid outlet groove (or hole), forming a continuous pumping effect.The whole working condition of this mechanical seals auxiliary system is similar to that of a centrifugal pump.
The centrifugal pumping ring of the mechanical seal auxiliary system requires that the fluid thrown out by the centrifugal force faces the outlet, and the structure of the outlet has a great influence on the circulation pressure. A common method is to process a groove on the corresponding outer cavity of the mechanical seal auxiliary system.The axial width of the groove includes the axial width of the centrifugal ring. At the same time, the annular groove is not circumferential.and is cut off near the rear side of the outlet hole, so that the fluid is forced to flow to the outlet hole. This design do not require high clearance of the parts.The pressure head outside the centrifugal pumping ring of the mechanical seal auxiliary system is mainly obtained by experiment. The spiral pumping ring is made of multi-threads on the outer surface of the rotating sleeve, which is used in conjunction with the inner surface of the stationary part outside the rotating sleeve (it will be better if the inner surface of the stationary part of the mechanical seal auxiliary system is processed with a thread opposite to that of the pumping ring, but usually due to the narrow space,the processing is difficult, and the inner surface of the stationary part is not threaded,but usually due to the narrow space, the processing is difficult, and the inner surface of the stationary part is not threaded), when the pumping ring of the mechanical seal auxiliary system rotates, the thread will drive the medium in the threaded groove to rotate, and due to the inertia, the medium in the threaded groove and the threaded groove produce relative motion, which promotes the sealing liquid moves to one side, causing a pressure difference on both sides of the pumping ring of the mechanical seal auxiliary system.
If you want to view other products，pls visit this website & component seals
