11
ENGLISH
INDUSTRIAL PNEUMATIC BUTTERFLY VALVE
10. TROUBLESHOOTING
FAULT
POSSIBLE CAUSE
FAULT CLEARANCE
The disc does not fully open
or close.
The sockets were not correctly
bevelled.
Disassemble the valve and bevel the
sockets as indicated in table T5.2.
Foreign materials in the compart-
ment (adhesive, etc.).
Disassemble the valve and check for
obstructions in the disc and gasket
contact area.
Excessive opening or closing
torque.
The valve has been inactive for a
long time.
Operate with an auxiliary release key
(not the plastic handle).
Disassemble the valve and lubricate
the sealing gasket.
High temperatures or chemicals can
cause damage to the gasket.
Check the chemical compatibility
of the liquid with the disc and the
working temperature. Replace the
gasket.
Excessive flange torque.
Tighten flanges as indicated in table
T5.1.
Misalignment between sockets and
valve.
Disassemble the valve and reas-
semble with concentric alignment
(observe the correct tightening
sequence and torque).
The valve is not completely
watertight in the sockets.
Misalignment between sockets and
valve.
Disassemble the valve and reas-
semble with concentric alignment
(observe the correct tightening
sequence and torque).
Flange screws not tight enough.
Tighten flanges as indicated in table
T5.1.
The valve is not completely
watertight at the sealing gasket.
Inadequate chemical resistance.
Temperature out of range.
Excess of pressure.
Abrasive elements.
Check compliance with the specifi-
cations in this document.
Damaged gasket.
Replace the gasket.
The valve does not open or close.
Lack of air pressure
Check air supply to the actuator.
The valve does not close
completely.
The actuator stroke is not properly
adjusted to the valve.
Check adjustment limits according
to the actuator manual.
The torque of the valve has in-
creased above the calculated value.
Check the valve: obstructions in the
disc or malfunction of the valve.
The valve does not change the
position.
The solenoid valve does not operate
properly due to the use of unfiltered
air.
Add filtration equipment to the air
supply input.
The solenoid does not work properly
due to impurities or oxidation by a
corrosive environment.
Change the solenoid valve and ask
the technical department about the
most appropriate solenoid valve.
