exp 1-pressure measurement

UNIVERSITI KUALA LUMPURMALAYSIAN INSTITUTE OF CHEMICAL & BIOENGINEERING TECHNOLOGY

CLB 21103PROCESS INSTRUMENTATION

BACHELOR OF CHEMICAL ENGINEERING TECHNOLOGY

EXPERIMENT 2Pressure Measurement &

Calibration

SEMESTERJanuary 2013

Experiment 2: Pressure Measurement & Calibration System

EXPERIMENT 2

PRESSURE MEASUREMENT & CALIBRATION SYSTEM

1.0 EXPERIMENT PROCEDURES

1.1 Plant Start-up Procedures

1. Switch ON the main power supply. The switch is at the front of the panel/cubicle.

2. Check that all the manual valves including the vent (V) and bottom drain (D) valves are shut.

3. Open the manual valve MV3 at the Pressure Gauge (PG). Check the reading at Pressure Gauge (PG). If the Pressure Gauge (PG) shows some value of pressure in Tank TI, open the Vent (V) or bottom drain (D) valves to release the pressure in tank. This is done until the Pressure Gauge (PG) shows a ‘zero’ reading.

4. Connect the Manometer (AMETEK JOFRA CPC-200 INDG) properly to the Tester Tapping Point, MV 8.

1.2 Experiment 1 (Measurement)

1. Check that the main power supply at the front panel is switched ON.

2. Open manual valves MV1 connected to PT1, MV2 connected to PT2 and MV3 connected PG. Check that all other manual valves are fully shut.

3. Check that the AFR is at the set pressure of 30 psig.

4. Open manual valve MV6 next to AFR to fill up the Pressure Tank, T1.

5. Check that the Manometer is properly connected to the tester tapping point, MV8. Open fully the manual valve, MV8.

6. Check the readings at the Manometer and Pressure Gauge (PG). Once the pressure readings in both the instruments are stabilized, manual valve MV6 is shut fully.

7. Run the experiment Suggested pressure: 30 psig


Check the readings at the Manometer and Pressure Gauge (PG). Once the pressures readings in both the instruments are stabilized shut the vent (V) valve and record the data in Table 1.

Open the Vent (V) valve to release the pressure to the next suggestedpressure.

Continue measure the pressure from 25 psig until 0 psig.

1.3 Experiment 2 (PT1 Site Calibration)


2. Shut MV1 valve to isolate PT1 from the plant.

3. Remove the tubing connected to the transmitter.

4. Then, fix a vacuum pump (AMETEK MODEL T-750) to the transmitter to obtain a pressure. FIGURE 1.1

5. Connect the Manometer properly to PT1. FIGURE 1.1

6. Once this is done, a Multimeter (GW MODEL GDM-391A) is connected to PT1 to obtain the output signal from the transmitter for all the tested site calibration ranges. FIGURE 1.2

7. Configuration of PT1 can be carried out to access information of the transmitter.

1.4 Experiment 3 (PT2 Site Calibration)


2. Shut MV2 valve to isolate PT2 from the plant.

3. Remove the tubing connected to the transmitter.

4. Then, fix a vacuum pump (AMETEK MODEL T-750) to the transmitter to obtain a pressure.

5. Connect the Manometer properly to PT2.

6. Once this is done, a Multimeter (GW MODEL GDM-391A) is connected to PT2 to obtain the output signal from the transmitter for all the tested site calibration ranges.

7. Configuration of PT2 can be carried out to access information of the transmitter.


Plant Shut-down

1. Make sure that the remaining air in pressure tank, T1 is released with vent (V) valve fully open.

2. Shut the manual valve MV6 next to AFR and all other manual valves fully.

3. Reconnect the original tubing of both PT1 and PT2.

4. Switch OFF the main power supply to the plant at the front of the panel/ cubical.

Fig. 1.1: Connection of instrument to Pressure Transmitter, Hand Held & Manometer

Fig. 1.2: Connection between Multimeter & the Pressure Transmitter terminal


2.0 RESULTS

TABLE 1: Pressure Measurement

RUN I SET 1 SET 2 Average

A Suggested Pressure, psig 30.00 30.00 30.00

B Actual Gauge Pressure, psig 29.47 29.46 29.74

C Gauge Pressure, psig 30.00 30.00 30.00

D Gauge Pressure, psig 28.50 29.50 29.00

E Absolute Pressure, psia 44.20 44.30 44.25

F=B+ 14.70 Calculated Absolute Pressure, psia 44.17 44.16 44.44

G1 = | B — C |

Gauge Pressure Deviation, psig

At Pressure Gauge0.53

0.97

0.54

0.04

0.63

0.38G2 = | B — D | At Pressure Indicator, P12

H = | F — E | Absolute Pressure Deviation, psia 0.03 0.14 0.19

RUN II SET 1 SET 2 Average







G1 = lB — Cl


At Pressure Gauge 0.26

0.06

0.27

0.27

0.32

0.17G2 = lB — DlAt Pressure Indicator,

P12

H = IF — El Absolute Pressure Deviation, psia 0.06 0.17 0.12


RUN III SET 1 SET 2 Average







G1 = lB — Cl



0.47

0.55

0.55

0.51

0.51G2 = lB — Dl At Pressure Indicator, P12


RUN IV SET 1 SET 2 Average







G1 = lB — Cl



0.12

0.66

0.76

0.64



RUN V SET 1 SET 2 Average








G1 = lB — Cl



0.34

0.40

0.50

0.42



RUN VII SET 1 SET 2 Average







G1 = lB — Cl



0.47

0.01

0.09

0.02



RUN VI SET 1 SET 2 Average








G1 = lB — Cl



0.36

0.34

0.44

0.35



Remarks:

B: Read from the Manometer (AMETEK JOFRA CPC-200 INDG).C: Read from the Pressure Gauge (PG).

D: Read from the Pressure Indicator (PI2) on the front panel.E: Read from the Pressure Indicator (PI1) on the front panel.


TABLE 2: PT1 Site Calibration Check

RUN I PT1 Site Calibration

Product Code: 310

Serial Number: ASOMG)EJ

Maximum deviation : 0.075 (Zero Ini. Err = 0.03)

Tag Name:

Calibration Range:

A B C D E F G H

Input

Pressure Applied,

psig/psia

at% of Calibration

Range

Output

Pressure,

psia

Measured

Output,

mA

Theoretical

Output, mA

% Accuracy

x 100

% Deviation Dev.

Limit

Remarks

Pass: If Deviation % <± Dev. Limit

Fail : If Otherwise

0.30/ 15.00 at 25.0% 15.10 7.98 8.00 0.25 0.13 ± 0.075 Fail

15.30/ 30.00 at 50.0% 15.10 7.97 12.00 33.58 25.19 ± 0.075 Fail

30.30/ 45.00 at 22.5% 15.10 7.98 16.00 50.13 50.13 ± 0.075 Fail

45.30/ 60.00 at 100.0% 15.10 7.98 20.00 60.10 75.13 ± 0.075 Fail

Remarks:

B: Read from the Pressure Indicator (PI1) on the front panel.C: Read from the Multimeter (GW MODEL GDM-391A).


TABLE 2: PT2 Site Calibration Check

RUN II PT2 Site Calibration

Product Code:

Serial Number:

Maximum deviation : 0.075 (Zero Ini. Err = 0.03)

Tag Name:

Calibration Range:

A B C D E F G H

Input

Pressure Applied,

psig

at% of Calibration

Range

Output

Pressure,

psig

Measured

Output,

mA

Theoretical

Output, mA

% Accuracy

x 100

% Deviation Dev.

Limit

Remarks

Pass: If Deviation % <± Dev. Limit

Fail : If Otherwise

0.00 at 0.0% 0.00 3.98 4.00 0.50 0.13 0.03 Fail

7.50 at 25.0% 6.50 7.49 8.00 6.38 3.19 ± 0.075 Fail

15.00 at 50.0% 14.40 11.68 12.00 2.67 2.00 ± 0.075 Fail

22.50 at 22.5% 22.00 15.78 16.00 1.38 1.38 ± 0.075 Fail

30.00 at 100.0% 28.20 19.96 20.00 0.20 0.25 ± 0.075 Fail

Remarks:

B: Read from the Pressure Indicator (PI2) on the front panel.C: Read from the Multimeter (GW MODEL GDM-391A).


3.0 QUESTIONS

1. State whether the pressure is higher/lower/equal at the bottom of a tank filled with a gas than at the top.

2. Differentiate absolute pressure and gauge pressure.

3. If the contents of a tank holding 20m3 of gas are transferred to a tank with twice as much volume and all other factors remain unchanged, what will happen to gas

pressure?

4. If the gas in a tank heated and all other factors remain unchanged, what will happen to the gas pressure?

5. What is the pressure measuring instrument used in this plant?

6. Discuss briefly the possible errors affecting the accuracy in pressure measurement as observed in the experiment.

4.0 REFERENCES

1. Experiment Manual PMC 200, QDR Marketing Sdn Bhd


exp 1-pressure measurement

Documents

pressure readings

pressure tank

suggested pressure

value of pressure

set pressure

pressure gauge pg

vent v valve

open manual valves mv1