Samson 3214, Mounting And Operating Instructions

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1 Design and principle of
operation
Fig. 1
The control valves consist of a Type 3214
Globe Valve balanced by a diaphragm and
an electric or electrohydraulic actuator.
The medium flows through the globe valves
in the direction indicated by the arrow on
the valve body. The cross-sectional area of
flow between the seat (2) and plug (3) is de-
termined by the position of the plug stem.
The downstream pressure p
2
is applied to
the inside of the Type 3214 Valve; the up-
stream pressure p
1
acts on the outside. The
forces acting on the valve plug due to the
upstream and downstream pressures are
balanced by the diaphragm (4).
The plug is moved by changing the control
signal applied to the actuator. For the
Type 3374 Electric Actuator as well as the
Type 3274 Electrohydraulic Actuator, this
signal is a three-step signal or, when an ad-
ditional electric positioner is used, a continu-
ous 0 to 20 mA, 4 to 20 mA or 0 (2) to
10 V– signal.
The electric actuators can be equipped with
additional accessories.
1.1 Versions
Electric control valve with Type 3214 Globe
Valve balanced by a diaphragm
Type PN DN EB*
3214/3374-10
16 to 40
125 to
250
8331-1
3214/3274-12
8340
3214/3274-16
3214/3274-23 **
* For details on the actuators refer to the listed
mounting and operating instructions (EB).
** Type 3274-23 Actuator with fail-safe func-
tion: typetesting available on request
4
EB 5868-1 EN
Design and principle of operation