Samson 41-73 Series, Монтаж и эксплуатация

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EB 2517 EN 3-1
Design and principle of operation
3 Design and principle of oper-
ation
Î
See Fig. 3-1
The Type 41-73 Excess Pressure Valve con -
sists of a Type 2417 Opening Valve and a
Type 2413 Actuator. The valve and actuator
(except for tested regulators) are delivered
separately and must be assembled together
according to these instructions (see the 'In-
stallation' section).
The excess pressure valve is used to maintain
the pressure upstream of the valve to an ad-
justed 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 upstream
pressure p
1
is transmitted over the compen-
sation chamber (18) and control line (17) to
the operating diaphragm (12) (operating
bellows (12.1) in the version with bellows
actuator) where it is converted into a posi-
tioning force. This force is used to move the
valve plug depending on the force of the set
point springs (7). The spring force is adjust-
able at the set point adjuster (6). The valves
with K
VS
4 and higher have a balancing bel -
lows (4). The upstream pressure acts on the
outside of the bellows and the downstream
pressure on the inside of the bellows. As a
result, the forces produced by the upstream
and downstream pressures acting on the
plug are balanced out.
The valve opens when the upstream pressure
rises.
Legend for Fig. 3-1
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
7.2 Nut
7.3 Cap screw
7.4
Needle bearing and axial disk
8 Crossbeam
8.1
Pillar
(view drawn turned by 90°)
8.2 Nuts for pillars
8.3 Tapped 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