Trouble Shooting 13～14 - SMC Networks AR20MK Series Operation Manual

9. Trouble Shooting
Refer to sections [10. How to Replace the Components] (P15-19) and [11. Disassembly Drawing] (P20-21).
Problem
Category Failure
The pressure
can not be
adjusted.
The set pressure
does not become
zero even when
the knob is
loosened.
Air leaks from
the bonnet
exhaust port.
Note ) Fluorine grease is recommended when applying additional grease.
Possible cause
1. Air pressure is not supplied to the
inlet.
2. The product is not correctly mounted
in the direction of flow.
3. Pressure regulating spring is
damaged.
4． Valve spring is damaged.
5. Foreign matter is caught in the valve
seat or valve sliding O-ring. In case
of back flow function type, foreign
matter may get caught in the check
seal.
6. Valve seat is damaged.
1. Foreign matter is caught in the valve
seat or valve sliding O-ring. In case
of back flow function type, foreign
matter may get caught in the check
valve seal.
2. Valve seat is damaged.
3. Valve spring is damaged.
4． The valve is fixed in an opened
position.
1. The product is not correctly mounted
in the direction of flow.
2. Diaphragm assembly is damaged.
3. Foreign matter is caught in seating
part of the relief valve.
4． Foreign matter got caught in the
valve seat or valve sliding O-ring. In
case of back flow function type,
foreign matter may get caught in the
check valve seal.
5. Valve seat is damaged.
Countermeasure
Check the supply pressure. Ensure that
the supply side ball valve is opened.
Install the product correctly after
confirming the direction of flow. The side
with "1" for IN and "2" is for OUT.
Replace the pressure regulating spring.
Replace the valve spring.
Remove the valve and eliminate foreign
materials.
When the condition is not improved,
replace the valve guide assembly and
valve assembly.
Replace the valve assembly.
Remove the valve and eliminate foreign
materials.
When the condition is not improved,
replace the valve guide assembly and
valve assembly.
Replace the valve assembly.
Replace the valve spring.
Clean the valve sliding surface of O-ring
and apply grease additionally.
Install the product correctly after
confirming the direction of flow. The side
with "1" for IN and "2" is for OUT.
Replace the diaphragm assembly.
Clean the seating part of the relief valve or
replace the diaphragm assembly.
Remove the valve guide and clean the
valve seat and valve sliding O-ring (or
check valve seal). After cleaning then,
apply grease to the valve sliding O-ring (or
check valve seal) and valve guide sliding
part.
Replace the valve assembly.
-13-
Page for
reference
―
―
P15
P16
P16
P16
P16
P16
P16
P16
―
P15
P15
P16
P16