Barton 227C, Руководство по установке

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6. Mount the DPU on a solid support to minimize vibration. Tighten all
points, using a suitable compound; leaks in piping can cause measurement
errors.
7. Rotate the housing as necessary to place the connection in the proper
position. The DPU has connections in the pressure housings to accommo-
date various pipe sizes (refer to Section 5 Outline Dimensional Drawing).
8. Install a valve manifold connecting the DPU and the source of differential
pressure to facilitate operation and checking of the DPU.
9. Install all shutoff and bypass valves so they are easily accessible from the
front of instrument. Locate block valves at the source of differential
pressure.
WARNING
HIGH PRESSURE HAZARD. TO PREVENT PERSONAL INJURY
OR DAMAGE TO EQUIPMENT, DIRECT ALL PIPING AWAY FROM
THE OPERATOR WHILE CONNECTING THE DPU TO THE
SYSTEM PIPING.
NOTICE
Do not share filling or vapor return lines with DPU piping lines.
Startup
Observe the following practices when starting up an instrument:
1.
Always start with the block valves closed.
2. Perform a zero check on the instrument as follows.
a. Open the bypass valve(s), then open one shutoff valve. This procedure
equalizes the pressure between both sides of the instrument. The
instrument should indicate zero.
b. If the instrument does not indicate zero, check for gas or liquid
entrapment in the lines or in the DPU (depending on the orientation of
the piping layout and service).
c. If necessary, adjust the pen or pointer by turning the zero adjust on the
instrument.
NOTE: For gas service, it is recommended that zero check be performed
with both block valves closed. If the gas flow is pulsating, there may be a
standing wave effect in the process line which can displace the indicator
and appear as a zero error.
3. Check the manifold and piping for leaks as follows.
a. Open the bypass valve(s), then open one shutoff valve to pressurize the
instrument.
b. Close the shutoff valve and the bypass valve.
c. Any leakage will be indicated by pen or pointer movement, up or down
scale.
NOTE: Be careful not to subject the DPU to unnecessary shock or
overrange pressure during operations.