Two-phase solid-liquid pump mechanical seal the correct selection of the use of (b)

Different from the general mechanical seal, the gap between the sleeve and the seal ring should be large. When there is material leakage, it can be discharged in time to avoid the accumulation and obstruction of particles. The design of the seal chamber must have adequate space to allow the material in the seal chamber to flow without settling and cooling and lubricating the seal. In order to reduce the media pressure on the seal end face pressure than the impact of the use of balanced mechanical seal structure. End pressure is one of the most important factors affecting the sealing performance and service life. In order to prevent the particle medium from entering the sealing end surface, the amount of leakage increases and the wear of the end surface aggravates, resulting in the failure of the sealing. The pressure on the end surface should be made larger than that of the normal one. But the end pressure is too large, will result in friction surface heating and wear increased, power consumption increases. Design, the end pressure is about 0.3MPa. When using single-end mechanical seal, in order to avoid the hazards of particle impurities, according to different situations need to take flushing, filtration, separation, isolation, insulation and heating and other measures. Rinsing fluid reliability and quality is the key to the success or failure of the seal. If the cleaning solution is injected externally, the working environment of the seal can be improved, but the cleaning solution must be wasted, and the precondition is that the fluid to be transported is allowed to dilute slightly with the processing solution. When using a double-ended mechanical seal, the seal liquid is required to establish pressure within the seal chamber for plugging, lubrication, and cooling cycles. Double-sided seal high reliability, but the higher manufacturing costs and installation costs. The choice of materials for most double-ended seal sets has been standardized. In actual use, the friction pair on the media end uses carbide pairs or silicon carbide pairs; the carbon graphite and nickel-chromium steel pairs on the atmosphere end are used. Shanxi Aluminum Plant currently used B173-125-type mechanical seal on the selection of the above aspects to consider. Its working parameters are as follows. Medium: with a small amount of aluminum hydroxide solid particles Pressure: 0.5MPa Speed: 480r / min Temperature: 120 ~ 150 ℃ B173-125 type mechanical seal is a single end, inflow machine seal. Use outside rinse solution. Friction deputy material selection of tungsten carbide on tungsten carbide. The performance parameters are as follows. Grades: YG6 Linear expansion coefficient: 4.5 ~ 5.0 × 10-6 / ℃ Temperature range: -10 ~ 450 ℃ Hardness: 89.5HRA Specific gravity: 14.6 ~ 15g / cm3 Bending strength: 1421MPa Tungsten carbide is characterized by high hardness And strength, good wear resistance, high temperature resistance. The mechanical seal is a cartridge seal, complete assembly, into the sealed chamber, installation and no special requirements. Operation, first flush valve open, then open the medium valve, and then start running. As the mechanical seal in the selection, considering the above conditions, therefore, the use of the process is very simple, just to ensure the continuity of external washing cooling, and the use of good results.