Mechanical seal surveillance: usually in the sealing surface uniform speed to indicate the sealing surface peripheral. The mechanical seal of the speed above 25 m / s is generally considered to be high-speed seal, with regard to high speed sealing, in order to avoid the effect of cephality and mixing and heat, the stop mechanical seal should be selected. The speed is high, the PV value is too high, and the central ring can be selected, or the fluid dynamic mechanical seal or fluid static pressing mechanical seal is selected.
Temperature: Typically, the temperature temperature is indicated in the sealing case. The sealing medium temperature is usually suitable for mechanical sealing at 80 ° C or lower. Regarding the gasification medium, the upper temperature should be 13.9 ° C which is lower than the boiling point, otherwise it is not possible to ensure a stable liquid film. Typically the medium temperature is in the range of 80-150 ° C for thermal commodity (preheating), and the temperature above 150 ° C is a high temperature seal. The temperature below -20 ° C is a low temperature seal, while the temperature below -50 ° C is deeply cold seal. In high, low-temperature sealing should not be taken in the information and construction, and there is also a cooling and insulation method in a counted approach.
Axial diameter: a large axial seal typically refers to a seal having an axial diameter of more than 120 mm; a small axial seal generally refers to a seal of less than 25 mm in an axial diameter.
Medium properties: About media with weaker corrosive, can be used in an in-house mechanical seal. With regard to the quality of the corrosive medium due to the selection of the leaf structure in the elastic element, it can be used for extensive mechanical sealing and low pressure. With regard to easy crystallization, easy-to-solid and high viscosity products, a single large leaf structure should be used, which is better than a plurality of points, and it is not easy to block. For flammable, explosive and toxic products, it is necessary to consider double-end or multi-stage seals to ensure sealed.
