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Chapter 7. Inspection and Maintenance
For routine inspection and maintenance, pay attention to the following:
7-1. Check for leakage from piping
Verify that there is no leakage from the pressure tap points of the piping at the meter body. If
any loose connections are found, tighten them securely.
7-2. Maintaining the meter body and piping
To ensure the instrument performing to specification, keep the meter body and its piping
clean. If sediment or any foreign matter is entrapped in the pressure chambers of the meter
body, measuring errors may result. To blow and clean the meter body and piping, proceed as
described below.
7-2-1. Blow procedure
When no blow pipes are provided
(1) Close the stop valve on the high pressure side tapping pipe and that of the high pressure
side of the manifold valve.
(2) Ensure that the equalizer valve is closed.
(3) Close the stop valve on the low pressure side tapping pipe and that of the low pressure side
of the manifold valve.
(4) Slowly open the both side vent plugs to release pressure, then fully close them.
(5) Open the stop valve on the high pressure side of the manifold valve and that on the high
pressure side tapping pipe.
(6) Open the equalizer and blow the piping via the high pressure side vent plug.
(7) Close the equalizer valve, the stop valve of the high pressure side of the manifold valve,
and that of the high pressure side tapping pipe.
(8) Open the stop valve on the low pressure side of the manifold valve and that on the low
pressure side tapping pipe.
(9) Open the equalizer valve and blow the piping from the low pressure side vent hole.
(10) Close all valves.
(11) Start operating the instrument following the procedure explained in the “Chapter 6 :
Operation Method”.
