EB 3131 EN
25
Mounting and start-up
5.2 Additional fittings
Strainer
A strainer installed upstream in the flow pipe
holds back any dirt or other foreign particles
carried along by the medium. For example,
the SAMSON Type 1 NI Strainer is suitable
(
u
−
Do not use the strainer to permanently
filter the process medium.
−
Install the strainer upstream of the regu-
lator.
−
The direction of flow must correspond to
the arrow on the valve body.
−
The filter element must be installed to
hang downward.
−
Allow sufficient space to remove the filter.
Shut-off valve
Install a hand-operated shut-off valve both
upstream of the strainer and at the outlet of
the return flow pipe (see Fig. 4). This allows
the plant to be shut down for cleaning and
maintenance, and when the plant is not used
for longer periods of time.
Pressure gauge
Install a pressure gauge at a suitable point to
monitor the pressures prevailing in the plant
(see Fig. 4).
Control line
Depending on the regulator version, a con-
trol line (standard: 6x1 mm pipe diameter)
must be adapted and mounted on site. Make
sure that the control line is free of dirt.
We recommend installing the control line for
tapping pressure from the pipeline at a dis-
tance of at least three times the nominal size
(DN) away from any pipe fittings (e.g. mani
-
folds, bends, branches or other valves), that
may cause turbulence in the flow.
How the lines are routed generally depends
on the installation site. Preferably connect the
control line to the side of the main pipe.
Î
Do not change the pipe diameter of the
main pipeline with an eccentric reducer.
Î
Refer to installation schematics (Fig. 4)
for line routing.
M
DN
min.
3 x DN
min.
3 x DN
min.
3 x DN
Control
line
Fig. 5:
Control line connection, depending on
how the pipeline is routed
