mechanical seals theory

The mechanical seal is used by one or several ends with relative sliding vertical axes for fluid pressure and tensile compensation mechanisms to maintain the action of consolidation, accompanied by a support seal to achieve a leakage resistance sealing device.
Structure used for static ring seals, rotary rings, elastic components, spring seat, fixing screws, rotary rings and fixed ring support rings seals, and other auxiliary parts, fixed in the defense
Dealers to prevent the rotation of the fixed ring.
Rotating rings and fixed rings can usually be compensated based on whether they have axial or non-axial capabilities
Compensation is also called compensation ring.
Mechanical seal leakage of fluid channels may have four channels: A, B, C and D.
C, D leakage channel is a fixed ring, and the seal between the gland, shell gland and the two is a static seal.
The B channel is between the rotating ring and the shaft seal, and when the surface is rubbed and worn, it can follow the compensation loop for micro-
In fact, the movement along the shaft is still a relatively static seal.
Therefore, these leaks are relatively easy to cause the channel to close.
The most commonly used static seal rubber O-ring or PTFE V-
Ring, but as a compensation, or a fixed rotating ring secondary seal, sometimes functional is achieved using a rubber elastic element, PTFE, or metal bellows structure.
The channel is a rotary ring and fixed ring seal in cooperation with the relative sliding of the dynamic seal, and the mechanical sealing device is the key to the main seal, the performance of the mechanical seal and the determination of the life.
Therefore, the processing requirements of the sealing surface are very high. in order to maintain the necessary lubrication film, the sealing surface must be strictly regulated-
The surface pressure of the cavity on the side of the unit area is too large to form a stable lubrication film, which will accelerate the end wear; 2.
The pressure is too small and the leakage increases.
Therefore, in order to obtain good sealing performance and sufficient service life, in the design and installation of mechanical seals, it is necessary to ensure that the pressure face value per unit area is within the most suitable range.
There are many mechanical seals for soft packing sealing, which have the following advantages: 1.
Sealing reliability for a long time
During operation, the sealing condition is very stable and the leakage is very small. According to rough statistics, the leakage of the soft packing seal is generally only 1/100. 2.
The service life in oil and water is long, generally up to 1 to 2 years of medium, usually more than 6 months in chemical Media. 3.
The friction power consumption and friction power of the small mechanical seal are only 10% to 50% of the soft packing seal.