Samson 3321 - Malfunctions; Troubleshooting

46 EB 8111/8112 EN
Malfunctions
8 Malfunctions
Depending on the operating conditions, check the valve at certain intervals to prevent possi-
ble failure before it can occur. Operators are responsible for drawing up an inspection plan.
SAMSON's After-sales Service department can support you to draw up an inspection plan
for your plant.
8.1 Troubleshooting
Malfunction Possible reasons Recommended action
Actuator or plug stem does not
move on demand.
Actuator is blocked. Check attachment.
Unblock the actuator.
Signal pressure too low Check the signal pressure.
Check the signal pressure line for
leakage.
No or incorrect power supply
connected.
Check the power supply and
connections.
Actuator or plug stem does not
move through the whole range.
Signal pressure too low Check the signal pressure.
Check the signal pressure line for
leakage.
No or incorrect power supply
connected.
Check the power supply and
connections.
The valve leaks to the atmo-
sphere (fugitive emissions).
The packing is defective. Replace packing (see sec-
tion7.2) or contact SAMSON's
After-sales Service department.
Flange joint loose or gasket
worn out.
Check the ange joint.
Replace gasket at the anged
joint (see section7.1 or contact
SAMSON's After-sales Service
department).
Increased ow through closed
valve (seat leakage)
Dirt or other foreign particles de-
posited between the seat and
plug.
Shut off the section of the pipe-
line and ush the valve.
Valve trim, particularly with soft
seat, is worn.
Replace seat and plug (see sec-
tion7.3 or contact SAMSON's
After-sales Service department).
Tip