SMC Networks AW20 Series Operational Manual page 28

Refer to sections [11. How to Replace the Components] (P28-40) and [12. Disassembly Drawing] (P41-44).
Trouble
Category Failure
Air leakage from
the bonnet
exhaust port.
Air leakage from
between the
bonnet and the
body.
Air leakage from
between the
body and the
bowl.
Air leakage from
the bowl.
Air leakage from
the drain cock.
Drain or air
continues
blowing out from
the drain
discharge of the
float type auto
drain.
Air does not flow
backwards.
Drain is not
discharging
when the drain
cock opens.
Too much drain
comes from the
piping on outlet
side.
Note) Fluorine grease is recommended when applying additional grease.
Possible cause
7. Back pressure exceeding the set
pressure is applied to the downstream.
1. Loosened bonnet screws.
2. Diaphragm is damaged.
1. Bowl seal is damaged.
1. Bowl is damaged.
1. Foreign matter caught in the valve of the
drain cock.
2. Seating part of the drain cock is
damaged.
1. Low supply pressure
2. The product is not mounted correctly.
3. Foreign matter is caught in the main
valve of the auto drain.
4. Main valve of the auto drain is broken.
5. Drain piping is long, or I.D. of the piping
is small. (Back pressure is applied.)
6. Drain discharging part and bowl seat are
damaged.
1. Product without backflow function is
used.
2. Foreign materials caught in the sliding
part of check valve, leading to
malfunction; or the check valve is fixed in
a closed position.
1. Blockage of outlet of the drain cock due
to solid foreign matter etc.
1. Drain level reaches the baffle.
Countermeasure
Revise the air circuit so that back pressure
does not exceed the set pressure.
Fasten the bonnet.
Replace the diaphragm assembly.
Replace the bowl seal.
Grease up before replacing the bowl seal.
Note)
Replace the bowl assembly.
(If the solvent is considered to be harmful,
replacement to the metal bowl is
recommended.)
Open the drain cock for a few seconds for
blowing.
Replace the bowl assembly.
Confirm the minimum operating pressure of
the auto drain.
Install the drain exhaust so that it will face
vertically downward.
Eliminate the dirt by manual discharge.
Replace the bowl assembly.
Be sure to connect the appropriate piping
for drain.
Replace the bowl assembly.
Check the product number if backflow
function is equipped.
Replace the check valve assembly.
Replace the bowl assembly.
Open the drain cock for discharging and
replace the element.
-27-
Page for
reference
-
P28
P28
P29-31
P29-31
P24-25
P29-31
P5
P13-20
P5
P24-25
P29-31
P6
P29-31
P9
P38
P29-31
P24-25
P32