Which is the best mechanical seal or packing seal?1

Which is the best mechanical seal or packing seal?

Packing seal is a traditional touch seal, which is widely used. The structure is simple, the replacement is convenient, the cost is low, and the application range is wide (it can be used for sealing in rotating, reciprocating, and helical motion), and axial movement is allowed for the rotating shaft. The disadvantage is that the sealing performance is slightly poor, the shaft does not allow the mechanical seal to have a large radial runout, the power consumption is large, the shaft is worn, and the service life is short. The packing seal is somewhat attached to the packing through the shaft surface, and the labyrinth-effect mechanical seal should reach the seal. Therefore, the sliding seal should be smoothed by a satisfactory liquid to ensure that the seal has a certain life, the so-called bearing effect. The packing also requires materials: 1. Certain elastic plasticity 2. Chemical stability 3. Impermeability 4. Good self-lubricity, small friction coefficient and wear resistance 5. Temperature resistance 6. Convenient assembly and disassembly, etc. Mechanical seals Good performance, stable performance, less leakage, low conflict power consumption, long service cycle, little wear on the shaft, can meet the requirements of various working conditions, widely used in petrochemical and other parts, but its complex mechanism, high production accuracy, quotation More expensive and inconvenient to repair. Mechanical seal, also known as end face seal, has at least one pair of end faces perpendicular to the axis of rotation. Under the effect of fluid pressure and compensation for mechanical external elastic force (or magnetic force), and the cooperation of auxiliary seals, this section of face adheres to and merges with the other end face. Relative to East China, so as to avoid leakage. Because the two sealing end faces are closely attached, a small gap is formed between the sealing end faces. When the pressurized medium passes through this gap, a very thin liquid film is formed, which causes resistance, prevents the leakage of the medium, and makes the end face smooth. This achieves a long-term sealing effect.