For pump Mechanical seal manufacturer What are the effects on pressure vessels

The packing seal is often used in occasions where the sealing requirements are not strict because of its wide material source, convenient processing, low price, simple structure, convenient maintenance and other characteristics. However, the corrosion resistance, heat resistance, lubricity, impermeability and other aspects cannot fully meet the needs of chemical production, and mechanical seals are gradually replacing them. Mechanical seal, also known as end face seal, is a "rotating shaft dynamic seal, which is an ideal seal form to solve the problem of rotating seal" at present. Mechanical seal for pressure vessels has been rapidly developed and widely used due to its advantages of small leakage, long service life, low power consumption, and no frequent maintenance. However, mechanical seals also have the disadvantages of complex structure, high manufacturing accuracy, difficult selection of friction pairs and other components, and high cost; Mechanical seal saves a variety of structures, but no matter what structure the pressure vessel is, it includes the sealing surface composed of output ring and static ring, buffer compensation mechanism composed of main components of output elastic element and auxiliary sealing ring. It is a typical mechanical seal structure,

1. Moving ring from static ring

2. Ballam

3. Spring

4. Spring seat

5. Fixing screw

6. Sealed cabinet

7. And anti rotation platinum

The possible leakage paths of mechanical seals are between the static ring and the pressure vessel pressure cover, the joint surface between the dynamic ring and the static ring, the dynamic ring and the shaft, and between the pressure cover and the pump body; Except Class A dynamic seal, the rest B, C and D are static seals. Static sealing is easier to achieve sealing effect, while dynamic sealing is more difficult to achieve sealing. Under the condition of high-speed relative sliding, good sealing and high wear resistance are required.

Therefore, the dynamic seal is the key component of the end sealing device, and its working principle. Mechanical seal is a sealing device composed of static ring and dynamic ring, which are connected with each other and rotate relatively; Sols are commonly used in centrifugal pumps with a single end density of 14. Now take it as an example to illustrate the sealing principle. The movable ring uses a sealing ring to fix the clothes pump shaft and rotate with the shaft. The stationary ring is fixed on the pump casing through the seal ring and anti rotation pin of the stationary ring and remains stationary. When the pump is running, the dynamic ring changes with the change of uranium. The relative movement between the dynamic ring and the stationary ring occurs at the contact end of the dynamic ring and the stationary ring, forming a pair of relatively sliding friction pairs. There is a small gap between the friction pair and a layer of liquid film on the sealing surface. In the working state, the left side of the moving ring acts on saving medium pressure and spring force, and the right side acts on saving liquid film pressure. The resultant force on the moving ring points to the right, so that the moving ring is tightly squeezed against the static ring, thus generating a certain pressure (sealing specific pressure) on the sealing face of the pressure vessel.

Due to the small clearance between the moving and stationary rings, the resistance of the medium passing through the sealing surface is large, which prevents the leakage of the medium and ensures the sealing effect. The existence of the liquid film can also lubricate the friction pair to reduce wear. During the relative sliding process between the moving ring and the stationary ring, the sealing surface is worn, and the moving ring can move axially to compensate, so as to ensure that the sealing surface always keeps in good contact.