Past costumes mechanical seal shaft seal stuffing of the boxes is designed for soft packing seal. It unsuitable for containing mechanical seal, not only the size is too small, the gap is too narrow, and the simple cylindrical shape is not right.
Abroad has developed to increase size of mechanical seal shaft seal standard. In addition United States _ dulamitai leks company and United Kingdom study on fluid dynamics research group in reasonable mechanical shaft seal sealing, its shape is not only conducive to fluid flow and heat in addition to, and should be conducive to removing solid particles, caused to seal a good surrounding environment.
Volatile emission control
Only the Elimination of visible fluid leak, rather than see volatile emission control, thus causing environmental pollution and for devices and physical danger. Overseas such as the United States friction society seal and lubrication engineers Technical Committee has developed SP-30 (1994), SP-32 (1990) and SP-33 (1991) with mechanical seal rotating machinery, compressors and screw the control volatile emission regulatory guidance. SP-30 is divided into three phases. Which expressly provides that blocking flow and buffer definitions and clarifying the concept of error, confusion. Blocking fluid is introduced between the double seal completely blocked the process fluid leak fluid into the surrounding environment. Blocking fluid pressure is always higher than sealed the process fluid pressure. Buffer fluid is between the double seal fluid as lubricant or buffering agents, the buffer fluid pressure is always lower than the sealed the process fluid pressure.