Yokogawa EJX530B - Manual (Page 24)

<5. Installing Impulse Piping>
5-2
IM 01C27F01-01EN
(3) Impulse Piping Slope
The impulse piping must be routed with only an
upward or downward slope. Even for horizontal
routing, the impulse piping should have a slope of
at least 1/10 to prevent condensate (or gases) from
accumulating in the pipes.
(4) Preventing Freezing
If there is any risk that the process fluid in the
impulse piping or transmitter could freeze, use a
steam jacket or heater to maintain the temperature
of the fluid.
NOTE
After completing the connections, close the
valves on the process pressure taps (main
valves), the valves at the transmitter (stop
valves), and the impulse piping drain valves,
so that condensate, sediment, dust and other
extraneous material cannot enter the impulse
piping.
5.2 Impulse Piping Connection
Examples
Figure 5.3 shows examples of typical impulse
piping connections. Before connecting the
transmitter to the process, study the transmitter
installation location, the process piping layout,
and the characteristics of the process fluid
(corrosiveness, toxicity, flammability, etc.), in order
to make appropriate changes and additions to the
connection configurations.
Note the following points when referring to these
piping examples.
• If the impulse line is long, bracing or supports
should be provided to prevent vibration.
• The impulse piping material used must
be compatible with the process pressure,
temperature, and other conditions.
• A variety of process pressure tap valves (main
valves) are available according to the type
of connection (flanged, screwed, welded),
construction (globe, gate, or ball valve),
temperature and pressure. Select the type of
valve most appropriate for the application.
F0503.ai
Tee
Stop
valve
Stop
valve
Drain valve
Drain plug
Union
or
flange
Union
or
flange
Tap valve
Figure 5.3 Impulse Piping Connection Examples