Testing Orifice Meters
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tered to correspond with those on the Type T meter. Therefore follow the instructions under Type T and apply them to Type C. TESTING STATIC RECORDERS The Static Recorder may be tested with either pressure or vacuum on the line by means of a test gauge similar to that shown in Fig. 1330.
Type C Static: Referring to Fig. 1663: (1) Close valve F. (2) Remove plug at Y and connect test gauge at this point.
(3) Open valve F; this will check the static at line pressure.
If it is desirable to check at morepointson the scale, (4) Close valve D. (5) Open valves AA. (6) Close valve B.
(7) Open valve D slowly; this will relieve the pressure or vacuum in the piping.
Type T Static: Referring to Fig. 1593: (1) Close D. (2) Open AA. (3) Close B and C. (4) Remove plug at X. (5) Connect test gauge at X. (6) Open valve C.
FIG. 1330
By slowly opening and closing valve D the pressure or vacuum is relieved or built up, and the gauge may be checked over the entire range up to the maximum line pressure. TESTING PROPORTIONAL METERS, USING ORIFICE METER AS STANDARD* In checking the accuracy of proportional meters it is the practice of some companies to use the orifice meter as a standard, rather than the " Funnel Meter." A complete description of such test is given below. An orifice flange union having a length of straight pipe equal to at least ten diameters on both inlet and outlet sides, is connected in the line in series with the proportional meter. It is immaterial on which side of the proportional meter the orifice meter is inserted, but there Courtesy of the United Natural Gas Co.
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