Samson 2357-1, Mounting And Operating Instructions

Page: 3 / 12

1 Design and principle of
operation
The pressure regulators 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 ad-
juster (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 dia-
phragm (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 functioning as
excess pressure
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 regula-
tor versions for PN 50.
EB 2557 EN
3
Design and principle of operation