Samson 2412 Series, Монтаж и эксплуатация

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14 EB 2512 EN
Design and principle of operation
3 Design and principle of oper-
ation
Î
Refer to Fig. 3
The Type 41-23 Pressure Reducing Valve
consists of a Type 2412 Closing Valve and a
Type 2413 Actuator. The valve and actuator
are delivered separately and must be assem-
bled according to the instructions in sec-
tion 6.1.1.
The pressure reducing valve is used to main-
tain the pressure downstream of the valve to
an adjusted set point.
The process medium flows through the valve
between seat (2) and plug (3) in the direc-
tion indicated by the arrow on the body. The
position of the valve plug determines the
flow rate and, as a result, the pressure ratio
across the valve. The plug stem is sealed by
a frictionless bellows (5.1). The downstream
pressure p
2
is transmitted over the compen-
sation chamber (18) (for liquids above
150 °C and for steam) and the control line
(17) to the operating diaphragm (12) (oper-
ating bellows (12.1) in the version with bel-
lows actuator) where it is converted into a
positioning force. This force is used to move
the valve plug depending on the force of the
set point springs (7). The spring force is ad-
justable at the set point adjuster (6). The
valves with K
VS
4 and higher have a balanc -
ing bellows (4). The upstream pressure acts
on the outside of the bellows and the down-
stream pressure on the inside of the bellows.
As a result, the forces produced by the up-
stream and downstream pressures acting on
the plug are balanced out.
Depending on the valve and actuator used,
the regulator can be upgraded to create a
pressure reducing valve for low flow rates, a
steam pressure reducing valve or a pressure
reducing valve with increased safety (actua-
tor with two diaphragms).
The valve closes when the downstream pres-
sure rises.
Legend for Fig. 3
1
Valve body
2 Seat
3
Plug
4
Balancing bellows
5
Plug stem
5.1 Bellows
6
Set point adjuster
7 Set point springs
7.1 Spring plate
8
Crossbeam
8.1 Pillar
(view drawn turned by 90°)
8.2 Nuts for pillars
8.3 Threaded holes
9
Fastening nuts
10 Diaphragm actuator/bellows actuator
11 Actuator stem
12 Operating diaphragm
12.1 Operating bellows
13 Diaphragm plate
14 Diaphragm plate nut
15 Nuts and bolts
16
Control line connection G ¼
(with screw joint with restriction when used
with steam)
17
Control line (to be provided on site)
(available as control line kit for direct
pressure tapping at the body
u
T 2595)
18 Compensation chamber
19 Filler plug
20 Travel stop cap with cotter pin