Periodic Testing; Service Work Preparations; Installing The Valve After Service Work - Samson 3730 Series Mounting And Operating Instructions

9.1 Periodic testing

Depending on the operating conditions,
check the actuator at certain intervals to pre-
vent possible failure before it can occur.
Plant operators are responsible for drawing
up an inspection and test plan.
Tip
Our after-sales service can support you in
drawing up an inspection and test plan for
your plant.

9.2 Service work preparations

1. Lay out the necessary material and tools
to have them ready for the intended
work.
2. Put the actuator out of operation (see the
'Decommissioning' chapter).
3. Remove the actuator from the valve (see
the 'Removal' chapter).
Note
To remove an actuator with "stem extends"
fail-safe action and/or with preloaded
springs, a certain signal pressure must be
applied to the actuator (see the 'Removal'
chapter). Afterwards, the signal pressure
must be removed and the air supply discon-
nected again and locked.
4. Relieve the compression from the pre-
loaded springs. See section 'Relieving the
spring compression in the actuator' in the
'Removal' chapter.
EB 8313-3 EN
5. Unthread and remove the bolts and nuts
including shims from around the dia-
phragm case. Keep the parts in a safe
place for later use.
The following service work can be per-
formed after preparation is completed:
− Replace the diaphragm (see Chap-
ter 9.4.1).
− Replace the actuator stem seals (see
Chapter 9.4.2).
9.3 Installing the valve after
service work
1. Mount the actuator onto the valve (see
the 'Installation' chapter).
2. Adjust the upper or lower bench range
values (see the 'Start-up' chapter).
Servicing and conversion
9-3