Samson 44-0 B, Mounting And Operating Instructions, Page: 15 / 66

EB 2626-1 EN 3-1
Design and principle of operation
3 Design and principle of oper -
ation
Î
See Fig. 3-1
The Type 44-0 B and Type 44-1 B Pressure
Reducing Valves consist of a single-seated
globe valve with integrated actuator unit.
The regulators mainly consist of the valve (1)
with seat (3), plug (2) and balancing bellows
(6) as well as a spring housing with operat
-
ing bellows (5), set point spring (7) and set
point adjuster (8)/set point screw (9).
The pressure reducing valves are used to
maintain the pressure downstream of the
valve to an adjusted set point.
The regulator is open when relieved of pres
-
sure. It closes when the downstream pressure
rises above the adjusted set point. The pro
-
cess medium flows through the valve be -
tween seat and plug in the direction indicat -
ed by the arrow on the body. The position of
the valve plug determines the flow rate and,
as a result, the downstream pressure.
The downstream pressure p
2
to be controlled
is transmitted through a borehole (4) in the
valve body to the operating bellows (5)
where it is converted into a positioning force.
This force is used to move the valve plug ac
-
cording to the force of the set point spring
(7). The spring force is adjustable at the set
point adjuster (8/9).
Legend for Fig. 3-1
1 Valve body
1.1 Body gasket
1.2
Seal
2 Plug
3 Seat
4 Borehole in body for downstream pressure
p
2
5 Operating bellows
6 Balancing bellows
7 Set point spring
8
Set point adjuster
9
Set point screw with stainless steel/
spheroidal graphite iron version
(DN 40/50) as well as 8 to 20 bar set
point range
10 Screws
11
Stopper
12 Spring housing