PNEUMATIC CONTROLLER
SERIES
SG6100
Page: 7
MAR-IN CONTROLS B.V. VAN UTRECHTWEG 8 –10 KRIMPEN A/D IJSSEL THE NETHERLANDS
Tel. + 31 (0)180 - 51 71 51 Fax +31 (0)180 - 51 89 14 [email protected] www.mar-in-controls.com
Pressure
- The instrument must be installed with block valves.
- Find out if the measuring instrument material is compatible with the process fluid.
- The pressure connection hole in pipe line or vessel should form a right angle with the fluid flow
direction, otherwise the instrument will not only record the static pressure but a value also
including the dynamical component.
Fig. 3 - Installation of pressure controllers
L
= line,
VS
= needle valves, • = plugs or points of vent or purge,
E
= pipe union,
V
= valves
Liquid pressure measurement:
Pressure connection should be made to the side of the vessel or line to prevent the intrusion of
sediments and vapours into the instrument. When the instrument is mounted above the pressure
connection , the height of the vertical leg to the instrument should not exceed 7.5 metres divided
by the specific gravity of liquid in the leg.
Steam pressure measurement:
Pressure connection should be made one top of the vessel or pipeline when the instrument is
mounted above or to the side. When the instrument is mounted below, the connection should be
made to the side to enable the vapours and sediments to escape into the line or vessel.
Wet gas pressure measurements:
If the instrument is installed above the line or vessel, the pressure connection should be made on
the top so that condenses or moistures can freely drain back into the line or vessel. When the
instrument is installed below pipeline or vessel level mount a pot with the relative filling liquid to
assure a constant level-height, the pressure connection will be to the side.
If there are pulsations a dampener should be installed. The measuring element cannot be
subjected an excessive temperature of 200 °C.
