Function
When the valve is closed (non-actuated position), there are always two seals between the separated pipelines. If one seal is defective, the resulting leakage will be directed through the leakage outlet into the periphery, without mixing with the product in the second pipeline.
Application Examples
VARIVENT® double-seal valves type C and double-seat valves type K are predominantly used in areas where hygienic is not critical, e.g. CIP systems and gas blocks (brewery)
The Valve Types
Valve type K represents a typical double-seat valve with two independent valve discs in which these two seals are located.
Valve type C, on the other hand, is a double-seal valve in which these two seals are together with the leakage chamber in between them in a valve disc.
In both versions, two seals prevent any mixture between a product line and a line carrying a cleaning media.
Sizes
Valve Selection Scheme: Mixproof Shut-off Valves
Cleaning the Leakage Chamber
Double-seal valve type C
In the standard version, two flushing valves are connected to the leakage chamber between the two valve disc seals.
One flushing valve is always used for the leakage outlet, while the second flushing valve is in contact with cleaning media through an olive screw fitting, in order to clean the leakage chamber.
In this case, it is necessary to have a supply valve connected in the periphery to supply the flushing valve with cleaning media at the required time.
Cleaning takes place while the main valve is closed, which means the seal surfaces of the valve disc seals that are in contact are not reached.
Cleaning the Leakage Chamber
Technical Data