wT 2575/11
Page
6
THE EXTERNAL SEALING SYSTEM
The sealing of the shifting shaft (operating stem) is carried out by a belleville washer supported stuffing
box.
This type of sealing is almost maintenance free and has just little set-off behaviour. Only small
tightening forces are required for leak tightness.
The arrangement of the belleville washer ensures that a constant contact pressure acts against the
stuffing box to compensate alternating temperature- and pressure changes.
WELT OF SEALING RING
The grove in the body prevents floating of the sealing ring in radial direction (1) against the back side (2)
and the bore (3). The ball presses against the sealing ring (4). Therefore the sealing ring can not set
down or flow, because it is surrounded on each side.
