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• Flow varies DIRECTLY as the square ROOT of DIFFERENT pressure F = K square root of ΔP.
• Since this flow varies as the square root of differential pressure the pen does not directly indicate flow.
• The flow can be DETERMINED by taking the square root of the pen. Say the pen reads 50% of CHART.

1. Air is vented by opening the vent plugs on a liquid SERVICE transmitter.
2. On services where seal pots are used ISOLATE the primary isolation valves and OPEN the vent valves. Fill the line from the transmitter drain plug with a pump.

NEW Factor = _!New RANGE OLD Factor = _IOld Range Flow = K_!Range

Q = Factor X Unit Flow

New Factor = Old Factor I _IOld Range X _/New Range.

New Factor = _!New Range Old Factor = _IOld Range Flow = K_!Range

Q = Factor X Unit Flow

New Factor = Old Factor I _IOld Range X _/New Range.

The procedure for glycol filling is :

1. CLOSE the primary ISOLATION valves.
2. Open the vent on the seal POTS.
3. DRAIN the USE glycol if present.
4. Connect a hand pump on L.P. side while filling the H.P. side with glycol.
5. Keep the equalizer valve open.
6. Keep the L.P. side valve closed.
7. Start pumping and fill glycol.
8. Same repeat for L.P. side by connecting pump to H.P. side, keeping equalizer open and H.P. side isolation valve closed.
9. Close the seal pot vent valves.
10. Close equalizer valve.
11. Open both the primary isolation valves.

The procedure for glycol filling is :

CLOSE one of the VALVE EITHER H.P. or L.P. open the equalizing valve. The O/P should read zero.

Close one of the valve either H.P. or L.P. open the equalizing valve. The O/P should read zero.

1. First flushing the transmitter. Flush both the impulse lines. Adjust the ZERO by equalizing if NECESSARY. If still the INDICATION is more then.
2. CHECK L.P. side for choke. If that is clean then.
3. Check the LEAKS on L.P. side. If not.
4. Calibrate the transmitter.

Liquid LINES: On liquid lines the TRANSMITTER is mounted below the orifice PLATE. Since liquids have a PROPERTY of self draining.

Gas Service: On gas service the transmitter is mounted above the orifice plate because GASES have a property of self venting and secondly condenlate formation.

Steam Service: On steam service the transmitter is mounted below the orifice plate with condenlate pots. The pots should be at the same level.

Liquid lines: On liquid lines the transmitter is mounted below the orifice plate. Since liquids have a property of self draining.

Gas Service: On gas service the transmitter is mounted above the orifice plate because Gases have a property of self venting and secondly condenlate formation.

Steam Service: On steam service the transmitter is mounted below the orifice plate with condenlate pots. The pots should be at the same level.

Glycol.

Glycol.

The following steps are to be taken which claribrating :

1. Adjust zero of the Xmtrs.
2. Static preasure TEST: Give equal pressure on both SIDES of the TRANSMITTER. Zero should not shift. If it is shifting carry out static alignment.
3. Vaccum test: Apply equal vaccum to both the sides. The zero should not shift.

Calibration Procedure:

• Give 20 PSI air supply to the transmitter.
• Vent the L.P. side to atmosphere.
• Connect output of the Instrument to a standard test gauge. Adjust zero.
• Apply required pressure to high pressure side of the transmitter and adjust the span.
• Adjust zero again if necessary.

The following steps are to be taken which claribrating :

Calibration Procedure:

The MARKING is ALWAYS DONE H. P. side of the orifice tab which gives an indication of the H.P.side.

The marking is always done H. P. side of the orifice tab which gives an indication of the H.P.side.

BERNOULLI’s theoram states the “total energy of a LIQUID flowing from one point to ANOTHER remains constant.” It is applicable for NON COMPRESSIBLE liquids.

Bernoulli’s theoram states the “total energy of a liquid flowing from one point to another remains constant.” It is applicable for non compressible liquids.

An orifice TAB is WELDED on the orifice plate which EXTENDS our of the line GIVING an indication of the orifice plate.

An orifice tab is welded on the orifice plate which extends our of the line giving an indication of the orifice plate.

The different types of orifice plates are:

1. Concentric.
2. Segmental.
3. Eccentric.

CONCENTRIC: The concentric orifice plate is used for ideal LIQUID as well as GASES and steam service. This orifice as a hole in concentric and hence known as concentric orifice.

Eccentric & Segmental: The eccentric orifice plate has a hole eccentric. The use this is made in viscous and sherry FLOW measurement.

The segmental orifice place has the hole in the form SEGMENT of a circle. This is used for colloidal and sherry flow measurement.

The different types of orifice plates are:

CONCENTRIC: The concentric orifice plate is used for ideal liquid as well as gases and steam service. This orifice as a hole in concentric and hence known as concentric orifice.

Eccentric & Segmental: The eccentric orifice plate has a hole eccentric. The use this is made in viscous and sherry flow measurement.

The segmental orifice place has the hole in the form segment of a circle. This is used for colloidal and sherry flow measurement.

The primary ELEMENTS used for FLOW measurement are:

1. ORIFICE PLATE.
2. Venturi tube.
3. Pitot tube.
4. Annubars.
5. Flow Nozzle.
6. Weir & Flumes.

The primary elements used for flow measurement are:

1. FLOW: Kg I hr, Litter I min, Gallon I min. M3 I NM3 I HR. (GASES)
2. PRESSURE: Force acting per UNIT Area. P = F/A Units: Bar I PASCALS I Kg I CM I, Pounds
3. LEVEL: Different between two heights. Units: Meters, M M, C M, %.
4. TEMPERATURE: It is the degree of hotness or coldness of a body. Units : Degree Centigrade, Degree FARENHEIT, Degree Kelvin, Degree Rankin.
5. QUALITY: It deals with analysis PH, % C02, % 02, Conductivity, VISCOSITY.

The process VARIABLE are:

1. FLOW
2. PRESSURE
3. TEMPERATURE
4. Level
5. Quality i. e. % D2, C02, PH etc.

The process Variable are: