Samson 2404-2, Монтаж и эксплуатация

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EB 2540 EN 3-1
Design and principle of operation
3 Design and principle of oper-
ation
Î
See Fig. 3-1
The following components interact to regu-
late the pressure of the inert gas.
The input pressure regulator (3) is delivered
ready-adjusted. It reduces the supply pres-
sure p (medium: inert gas or compressed air)
to the input pressure p
e
for the pilot valve (2)
to approx. 1 bar/15 psi (positive pressure),
ensuring precise pressure control even at
varying upstream pressures.
The pilot valve (2) compares the actual pres-
sure with the set point pressure. In the idle
state, the pilot valve is closed by the force of
the set point spring (2.1).
The upstream pressure p
1
to be controlled is
routed to the pilot valve over the control line
(2.4). The force created by the upstream
pressure p
1
at the operating diaphragm
(2.2) is compared with the adjusted spring
force of the set point spring. The pilot valve
opens when the blanketing gas pressure in
the tank rises above the adjusted set point.
This causes the control pressure p
S
to in-
crease as well. The main valve also starts to
open when the force of the control pressure
p
S
acting on the actuator diaphragm (1.2) in
the main valve (1) is greater than the force of
the closing spring (1.1). As a result, the
blanketing gas is vented to the atmosphere
or recovered for processing until the tank
blanketing is re-stabilized or the pressure
falls below adjusted set point.
The needle valve (4) is delivered ready-ad-
justed and lead-sealed.
Optionally, the outlet (
1 /
8
NPT) of the needle
valve (4) can be routed to the downstream
pressure (p
2
) side of the main valve.
Note