Samson 44-7 Mounting And Operating Instructions page 31

Table 5: Troubleshooting
Malfunction
Upstream pressure
exceeds the adjusted
set point.
Pressure drops below
the adjusted set point.
Jerky control
response
Slow control response
EB 2723 EN
Possible reasons
Insufficient pressure pulses on the
operating diaphragm.
Pressure tapped at the wrong place
(regulator with external control line).
Regulator installed against the flow.
Regulator or K /C coefficient too
VS V
small
Foreign particles blocking the plug
Defective operating diaphragm
Seal the inspection borehole.
Foreign particles blocking the plug
Seat and plug are worn or leak.
Pressure tapped at the wrong place
(regulator with external control line).
Regulator or K /C coefficient too
VS V
large
Control line blocked
Strainer blocked.
Increased friction, e.g. due to
foreign particles between seat and
plug or in the stem guide on the
bonnet.
Control line blocked by dirt causing
the flow through it to be restricted.
Recommended action
Î Connect the control line on site for regulators
with external control line.
Î Clean the control line and screw fittings.
Î Reconnect the control line at another point.
Î Do not connect the control line at pipe bends or
necks.
Î Install the regulator so that the direction of flow
matches the direction indicated by the arrow on
the body.
Î Check the sizing.
Î Change K /C coefficient, if necessary or install
VS V
a different sized regulator.
Î Remove foreign particles.
Î Replace damaged parts.
Î Replace damaged diaphragm.
Î Open the inspection borehole.
Î Remove foreign particles.
Î Replace damaged parts.
Î Replace the damaged seat and plug.
Î Reconnect the control line at another point.
Î Do not connect the control line at pipe bends or
necks.
Î Check the sizing.
Î Change K /C coefficient, if necessary or install
VS V
a different sized regulator.
Î Clean the control line and screw fittings.
Î Clean strainer.
Î Remove foreign particles.
Î Replace damaged parts.
Î Clean the control line.
Malfunctions
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