wT 1209/11
Page 5
Hazardous Operating Errors and Possible Sources of Danger
Piston valves provide a particularly good seal. During Temperature changes, process fluid captured
between two piston valves can cause considerable changes in pressure which may exceed the
pressure category of the valve. In such cases, appropriate volume compensation (expansion tank) is
necessary.
Always ensure that the correct tightening torque specified in the Technical Data Sheet on Page 11 is
applied to the bonnet hexagon nuts.
Do not loosen or undo these nuts while the valves are under pressure.
The valves must no be subjected to pressure shock in excess of one and a half times their rated
pressure.
When the spindle thread becomes so worn out that its stability seems endangered, release the pressure
and carry out the necessary maintenance.
Whatever the application, always consult the operating limits diagram (pressure-temperature) and also
consider the suitability of the materials for various process fluids.
Maintenance and Repair Instructions for
KLINGER – PISTON - VALVES (KVN Models)
Klinger piston valves are easy to repair using simple assembly and dismantling tools. The valve does
not have to be removed
, but the line system must be
depressurised
and
emptied.
We recommend the following procedure for dismantling:
•
Depressurise and empty the system
•
Open the valve fully
•
Unscrew the stud bolt (25), then unmeant Belleville washers (33)
•
Turn the hand wheel (3) clockwise (closing direction),at the same time bonnet (2) rises out of body
•
Turn bonnet slightly until the flange adjoin against the stud bolt faces (25) and turn hand wheel anti-
clockwise (opening direction) until the piston (4) is completely free of the top valve ring (14),
(see Fig.1)