Dungs FRM 100025 HD, Instruction Manual, Page: 37 / 174

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FRM
Ÿ
Edition 10.15
Ÿ
270 440
Function
Sectional drawing FRM
Pressure regulator in open position
1 Control plate
2 Inlet pressure compensation
diaphragm
3 Lower diaphragm shell
4 Lever system
5 Impulse connection for the outlet pressure
6 Working diaphragm
7 Vent connection
8 Setpoint spring
Any condensate from impulse lines must
not flow into the pressure regulator.
Combustible gas and gas/air mixtures
must not enter the installation space of
the adjusting spring.
In case of an increase of the outlet pressure, the
working diaphram 6 is pushed upwards, until the
force of the setpoint spring 8 is equal to that of the
outlet pressure.
The upward movement of the working diaphragm
6 causes the lever system 4 to be pulled upwards.
In this way, the control plate 1 is then pushed
downwards and the valve gap is reduced.
The flow volume decreased in this way reduces
the outlet pressure until the set nominal value
(outlet pressure) is reached and a balance of forc -
es at the working diaphragm 6 is established.
1
2
3
5
8
7
6
4
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Table of contents
Mode of operation according to the force
comparison principle between the force:
• of the adjustable setpoint spring,
• of the defined return spring,
• coming from the differential pressure on the
working diaphragm and
• of the weight of the movable parts.
The setting spring acts independently of the
weight of the movable parts. The outlet pres -
sure is set depending on the preload of the
setting spring.
Information
Gas-conveying lines, pulse and connecting
lines must be resistant to thermal, chemical and
mechanical stresses. They also must be dura-
ble and resistant to deformation and cracks.