Series 65  DESIGN AND FUNCTION 
 
963283EA  Edition 2019-05-03  15/
 
3.2  Function 
The valve plate acts, due to its pendulum motion, as a throttling element and varies the conductance 
of the valve opening. The integrated controller calculates the required plate position to achieve the set 
point pressure. Actuation is performed by a stepper motor. An encoder monitors the position. This 
principle ensures fast and accurate process pressure control. 
 
For opening or control the “sealing ring” is lifted pneumatically by “compressed air”, afterwards the 
“pendulum plate” moves to open or do pressure control. For leak tight closing, the “sealing ring” 
moves downwards and press the pendulum plate to valve body for “isolation”. Closing is performed by 
“springs”. 
 
 
 
 
“open / 
pressure 
control” 
“isolation”  
close 
sealing ring 
pendulum plate 
“compressed air” 
sealing ring 
pendulum plate 
springs