Samson 2333 series, Монтаж и эксплуатация

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6 EB 2552-1 EN
Design and principle of operation
3 Design and principle of op -
eration
See Fig. 1 and Fig. 2.
The medium flows through the globe valve (1)
in the direction indicated by the arrow. The
position of the plug determines the flow rate
across the area released between plug (3)
and valve seat (2). The travel position of the
pilot valve (5) determines the pressure condi-
tions across the valve.
The forces created by the upstream pressure
p
1
acting on the plug surface and by the con-
trol pressure p
S
acting on the balancing bel-
lows (4) or balancing diaphragm (11) and
the force of positioning spring (3.1) are com-
pared.
In the Type 2333 Pressure Reducing Valve, a
rise in downstream pressure p
2
causes the pi-
lot valve to close. The control pressure p
S
in-
creases, and the plug of the main valve starts
to close. When the pilot valve is closed (p
S
=
p
1
), the pressure reducing valve (main valve)
is also completely closed.
Together with the pilot valve, the fixed restric -
tion (8) or the Venturi nozzle (6) create the
control pressure p
S
.
If the downstream pressure p
2
falls again be-
low the set point, the pilot valve opens. The
control pressure p
S
falls as a result. The force
resulting from the upstream pressure p
1
acting
on the plug surface causes the valve to open.
To ensure proper functioning, the minimum
differential pressure ∆p
min
listed in Table 1
must be available as specified depending on
the field of application.
The regulator version for steam is only avail-
able with valves balanced by a bellows. This
version has a condensation chamber (10) al-
ready fitted in the control line. The needle
valve (9) is open and lead-sealed.
Before start-up, fill the condensation chamber
with water at the top filler opening.
Table 1: Minimum differential pressure ∆ p
min
Nominal size DN 125 DN 150 DN 200 DN 250 DN 300 DN 400
Minimum
differential
pressure ∆p
min
Valve balanced by
a bellows for steam
applications
1.9 bar 2.0 bar 1.4 bar 1.4 bar – –
Valve balanced by a
bellows for air/water
1.0 bar 1.0 bar 0.7 bar 0.7 bar – –
Valve balanced by a
diaphragm
0.8 bar 0.8 bar 0.4 bar 0.4 bar 0.5 bar 0.3 bar