A compressor relieves pressure via the piston rod packing after shutdown. The installation of a static pa (a Zero Emmision Sealing Solution) prevents the escape of process gas into the atmosphere during machine downtime, therefore avoiding any leakages, and resulting in a zero emission system.
After compressor shutdown, the static pack is activated via a controlled supply of process gas; therefore, an additional gas source is not needed.
The static pack consists of piston, follower, sealing lip, supporting rings, O-rings and pressure spring.
MODE OF OPERATION
Activation pressure moves the piston and presses the follower onto the sealing lip. Thereby the sealing lip is smoothly pressed against the rod and seals towards the cylinder. The sealing lip is guided by the supporting rings. Minor eccentricities of the piston rod can be compensated, since this is a "floating" design.
It is recommended to replace the static pack together with the internal parts of the piston rod packing even if the static pack is not worn out. Therefore, together with a set of internal parts a static pack will always be delivered as well.
It’s very important that the machine and the pis-ton rod are stopped before the static pack is activated. Additional, it must be guaranteed that the static pack is deactivated, i.e. pressure less before the machine is started. Otherwise, the sealing lip can be damaged.