The operating characteristics of the Mechanical Seals Manufacturer  for the easy-to-vaporize medium pump:

In the petrochemical industry, the safe operation of pumps for easily vaporized media (such as pumps for light hydrocarbon media) mainly depends on the reliability of the shaft seal. Because most light hydrocarbon media are flammable and explosive dangerous substances, such as methane, ethane, propane, butane, ethylene, propane, propylene, etc. These media not only have the characteristics of low boiling point and easy vaporization, but also have the characteristics of high vapor pressure, low viscosity, low ignition point, and high pollution. For mechanical seals that seal such media, it is difficult to maintain a stable fluid film between the end faces due to the easy vaporization of the fluid, and the gas-liquid mixed phase is in an unstable friction state, and phenomena such as "steam spray" and "squealing" occur, and even the sealing end faces are completely opened. And serious leakage, or in a state of severe dry friction, the early failure of the seal. Therefore, the sealing problem of light hydrocarbon pumps has always been a practical problem that plagues long-term safe production.

 At present, for the transport of light hydrocarbons and other easily vaporized medium pumps, the domestic mainly use single-end, double-end, series and other contact mechanical seal structure types.

For single-end contact Sealing Ring Manufacturer for light hydrocarbon pumps (as shown in Figure 9-9), there is not a complete liquid film between the sealing end surfaces. On the one hand, the temperature of the sealing surface increases due to a large amount of frictional heat generated at the friction end surface, which promotes the end surface

 On the other hand, since the saturated vapor pressure of light hydrocarbons is higher than the ambient atmospheric pressure (Fig. 9-10), a pressure drop occurs when the light hydrocarbon medium flows through the gap between the sealed end faces, Vaporization must occur at a certain position, that is, a phase change occurs. Therefore, according to the different phases of the end-face fluid film, it can be divided into liquid-phase sealing, gas-phase sealing or gas-liquid mixed-phase sealing.