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Self-operated Pressure Regulators
Pressure Reducing Valve Type 2357-1/-6
Excess Pressure Valve Type 2357-2/-7
Type 2357-1 Pressure
Reducing Valve
Type 2357-2 Excess
Pressure Valve
Type 2357-6 Pressure
Reducing Valve
Mounting and
Operating Instructions
EB 2557 EN
Edition April 2011
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Contents
Contents Page
1 Design and principle of operation . . . . . . . . . . . . . . . . . . . . . . 3
2 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 Mounting position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Shut-off valve and pressure gauge . . . . . . . . . . . . . . . . . . . . . . 5
3 Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1 Set point adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2 Changing the set point range. . . . . . . . . . . . . . . . . . . . . . . . . 7
4 Dimensions in mm and weights . . . . . . . . . . . . . . . . . . . . . . . 9
General safety instructions
The regulators must be installed, started up and serviced by fully trained and
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qualified personnel only, observing the accepted industry codes and
practices. Make sure employees or third persons are not exposed to any
danger.
All safety instructions and warnings in these instructions, particularly those
concerning installation, start-up and maintenance, must be observed.
For appropriate operation, make sure that the regulator is only used in
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applications where the operating pressure and temperatures do not exceed
the operating values based on the sizing data submitted in the order.
Note that the manufacturer does not assume any responsibility for damage
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caused by external forces or any other external factors.
Any hazards which could be caused in the regulator by the process medium
or operating pressure are to be prevented by means of appropriate
measures.
Proper shipping and appropriate storage are assumed.
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The declaration of conformity issued for a valve bearing the CE marking
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includes information on the applied conformity assessment procedure and
will be provided on request.
2 EB 2557 EN
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Design and principle of operation
1 Design and principle of
operation
The pressureregulators maintain the pressure
at an adjusted set point and are particularly
suitable for cryogenic applications.
Type 2357-1 and Type 2357-6 Regulators
(globe valves)
The regulators act as pressure reducing
valves when the medium flows from port A to
port B. When no pressure is applied, the
valve is open.
The pressure downstream of the valve B is
transmitted to the operating diaphragm (3).
The resulting positioning force moves the
valve plug (2) in relation to the spring force,
which can be adjusted at the set point adjuster (10). The valve closes as the pressure
downstream of the valve B increases.
When the regulators are used as pressure
build-up regulators, the medium flows from
port B to port A. The pressure upstream of the
valve (B) is transmitted to the operating diaphragm (3). The valve closes as the pressure
upstream of the valve increases and opens as
the upstream pressure drops.
The pressure build-up regulator additionally
assumes the function of a safety valve,
depressurizing the pressurized valve when
the set point is exceeded by more than 5 bar.
When the pressure has overcome the force of
the springs located on top, the valve opens to
balance the pressures.
Type 2357-2 and Type 2357-7 Regulators
(angle valves)
The regulators functioningas excesspressure
valves, the medium always flows from port A
to port B. When no pressure is applied, the
valve is closed. The pressure at port A acts on
the operating diaphragm (3) in the valve
body. The resulting force opposes the adjust
able spring force. As the pressure increases,
the valve opens until the set point is reached.
Regulators functioning as excess pressure
valves can optionally be equipped with a
non-return unit (12) which prevents the me
dium from flowing back.
EC type examination
An EC type examination according to the
Pressure Equipment Directive 97/23/EC,
Module B has been performed on the regulator versions for PN 50.
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EB 2557 EN 3
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Design and principle of operation
B
1
2
13
13
3
AA
B
12
1
3
4
13
4
5
5
6
6
7
8
9
8
9
10
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1 Body
2 Plug
3 Operating diaphragm
4 Gasket
5 Diaphragm plate
6 Ball
Fig. 1 · Sectional drawings of Type 2357-1/-6 (left) and Type 2357-2/-7 (right)
7 Spring plate
8 Set point spring(s)
9 Lower section of body
10 Set point adjuster
11 Lock nut
12 Non-return unit
13 Strainer
4 EB 2557 EN
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