Method Statement for Instrument Calibration

(1)

PURPOSE

Purpose of this procedure is to describe the minimum requirements for the calibration of instruments before installation, after installation and prior to commissioning.

DEFINITIONS

The initial non-operational checking for field instruments to be performed at calibration workshop before installation, to ensure that each instrument is functionally correct and correctly calibrated.

APPLICABLE CODE, STANDARD AND SPECIFICATION GENERAL PROCEDURES

4.1 All testing and calibration of instruments shall be equipped by subcontractor. All apparatus and testing equipments used for testing and calibrating instruments shall be described in “appendix-1”. The workshop shall be equipped with stabilized power supplies and clean, oil and water free, and dry instrument air supply facilities. Testing Facilities shall be fully equipped atmospherically controlled conditions.

4.2 All apparatus and testing equipment shall be validated with certificates from national and international authorized calibration agency.

4.3 All instruments shall be inspected for any visual damage and to ensure that they have been supplied in accordance with Data Requisition Sheets, Instrument Datasheets and Manufacturers (Vendors) Datasheets. 4.4 RFI (Request for Inspection) notification shall be submitted to invite

Owner’s supervisors.

4.5 Before commencement of tests or calibration of instruments, reference shall be made to the manufacturer's instructions. These instructions shall be adhered to. Should there be any uncertainty in the interpretation of such instructions, then shall be confirmed to the manufacturer.

4.6 Only personnel fully conversant and qualified with the types of instrument to be tested and calibrated shall be used. Qualification certificates shall be available for review at anytime.

4.7 When testing or calibration is complete, all connections and entries shall be checked that they are sealed to prevent ingress of gasses, vapor, 4

(2)

moisture and dirt. For each instrument a completed test or calibration document in accordance with Contractor’s QC forms shall be submitted to Owner. Calibration Supervisor shall maintain a detailed record of satisfactorily completed inspections, tests and calibrations.

4.8 Measuring or indicating instruments having mechanical movements shall belightly tapped during calibration at each checkpoint to overcome inherenthysterics.

4.9 Ranges, set point, date of calibration and the name of the person calibrating the instrument shall be noted on the self-adhesive labels attached to the calibrated instrument.

4.10 All applicable certificates such as NACE, PMI, Electrical apparatus, Factory Seat Leakage test Record, etc shall be available and form part of the test dossiers.

WORKSHOP CALIBRATION

5.1 All transmitters associated with the Process Control System and/or any other safety system shall be calibrated / tested from the primary element through to the output terminals. Actual pressure shall be applied to the transmitter process connection and a full five point calibration carried out. Full calibration tests shall be carried out on all pressure differential pressure and DP type level transmitters.

5.2 Temperature transmitters shall have a simulated RTD input injected at the input terminals for a full five point calibration check. RTD primary elements shall be tested at ambient and 100°C.

5.3 Ranges used in the calibration checks shall be in accordance with the latest instrument specification sheet. Vendor calibration sheet shall only be used as reference documents.

WORKSHOP CALIBRATION PROCEDURE

6.1 Electronic Pressure / Differential Pressure Transmitter (FT, LT, PT AND DPT)

Test Equipment Required: 4

(3)

- Dead Weight Tester / Hand pump - Digital multi-meter

- Hart Communicator Calibration Procedure:

- Visual inspection to confirm compliance of materials, mechanical construction, process and electrical connection and applicable certification validity and no damage during shipment.

- Apply a supply voltage of 24VDC to of transmitter and make series connection with digital multi-meter for output reading.

- Apply actuating pressure equivalent to 0%, 25%, 50%, 75%, 100%, 75%, 50%, 25% and 0% of the range specify on data sheet and observe the transmitter output at each point.

- If the transmitter output is not within the manufacturer’s tolerance, calibrate the transmitter in accordance with the manufacturer’s recommendations.

- Transmitter with indicating scales shall where necessary have their indicators calibrated during this check.

- Smart electronic type transmitters shall be functionally tested by using a HART COMMUNICATOR to confirm the device smartness and its required data population.

6.2 Differential Pressure Type Level Transmitter Test Equipment Required:

- Dead Weight Tester / Hand pump - Digital multi-meter

- Apply a supply voltage of 24VDC to of transmitter and make series connection with digital multi-meter for output reading.

- Apply actuating pressure equivalent to 0%, 25%, 50%, 75%, 100%, 75%, 50%, 25% and 0% of the range specify on data sheet and observe the transmitter output at each point.

4

(4)

- If the transmitter output is not within the manufacturer’s tolerance, calibrate the transmitter in accordance with the manufacturer’s recommendations.

- Transmitter with indicating scales shall where necessary have their indicators calibrated during this check.

6.3 Temperature Transmitter Test Equipment Required: - Temperature Calibrator - Digital Multi-meter - Decade Box

- Apply a supply voltage of 24VDC according to the type of transmitter and make series connection with digital multi-meter for output reading.

- Simulate upstream temperature signal equivalent to 0%, 25%, 50%, 75% and 100% of the range specify on the data sheet and observe the transmitter output. Record the corresponding readings.

- Simulate downstream temperature signal equivalent to 100%, 75%, 50%, 25% and 0% of the range specify on the data sheet and observe the transmitter output. Record the corresponding readings. - If the transmitter output is not within the manufacturer’s tolerance,

calibrate the transmitter in accordance with the manufacturer’s recommendations.

6.4 Temperature Element (RTD) Test Equipment Required: 4

4 4

(5)

- Temperature Calibrator - Digital Multi-meter Calibration Procedure:

- Connect the element to Temperature Calibrator.

- Allow the temperature to stabilize to ambient temperature and record the reading of the temperature calibrator.

- Increase heater to 100°C and record the reading of the temperature calibrator. Compare result obtain with temperature indicate on digital thermometer.

- The results should be within the manufacture’s tolerance of ambient temperature.

6.5 Pressure Gauge

Test Equipment Required:

- Dead Weight Tester / Hand pump - Digital Manometer

- Test Gauge

Calibration Procedure:

- Obtain the required actuating pressure by dead weight tester, variable air supply or hand operated air pump.

- Check that the pointer indicates 0 kpa reading under atmospheric condition. Where necessary zero adjustment shall be made. Record the pointer indication value.

- Increase actuating pressure equivalent to 0%, 25%, 50%, 75% and 100%. Where necessary span adjustment shall be made. Record the pointer indication values.

- Decrease actuating pressure equivalent to 100%, 75%, 50%, 25% and 0%. Record the pointer indication value.

- The percentage error calculated from the above readings shall not exceed Manufacturer’s Stated Limit.

6.6 Differential Pressure Gauge Test Equipment Required: - Hand pump

(6)

- Test Gauge

- Obtain the required actuating pressure by hand-operated air pump.

- Check that the pointer indicates 0 mmH2O reading under atmospheric condition. Where necessary zero adjustment shall be made. Record the pointer indication value.

- Increase actuating pressure equivalent to 0%, 25%, 50%, 75% and 100%. Where necessary span adjustment shall be made. Record the pointer indication values.

- Decrease actuating pressure equivalent to 100%, 75%, 50%, 25% and 0%. Record the pointer indication value.

6.7 Temperature Gauge Test Equipment Required:

- Temperature Calibrator/Oil Bath - Thermometer

- Compare Thermo Gauge pointer indication with the certified digital thermometer at ambient temperature. Where necessary Thermo Gauge pointer adjustment shall be made for synchronization with the digital thermometer. Record the pointer indication value.

- Immerse Thermo Gauge in temperature bath with certified glass thermometer.

- Increase bath temperature equivalent to 100°C. Record the pointer indications.

- The negative range (minus degree °C) does not require any check. 6.8 Local Indicator (Electronic Type)

Test Equipment Required: - Digital Multi-meter - Current Injector (mA)

(7)

- Apply calibration signal 4 ~ 20 mA to the Local indicator and observed the output percentage on the display.

- Increased and decrease the applied signal to 0%, 25%, 50%, 75% and 100% of mA. Observed the output which displayed on the local indicator is equivalent to 0%, 25%, 50%, 75% and 100%.

- Confirm “Open” and “Close” limit switches status. 6.9 Orifice Plate

Test Equipment Required: - Digital Caliper

Verification Procedure:

- Visual check on the surface for the presence of scratches or bowing. - The correct bore size as measured by internal digital caliper.

- Correctly stamped identification and bore dimensions on upstream face of tag handle.

6.10 Restriction Orifice Test Equipment Required: - Digital Caliper

Verification Procedure:

- Visual check on the surface for the presence of scratches or bowing. - The correct bore size as measured by internal digital caliper.

- Correctly stamped identification and bore dimensions on upstream face of tag handle. 6.11 Control Valves 6.11.1 Test Equipment a. Nitrogen cylinder. b. mA generator c. 24VDC power supplier d. Digital Multi meter.

e. P&F amplifier for proximity switch 6.11.2 Calibration Procedure

(8)

a. Check and confirm control valve air supply (kg/cm2_{) required and} transducer/valve positioner and accessories data against manufacturer’s data sheet.

b. Review manufacturer factory certificates and FAT Report, PMI, etc… c. Check control valve damaged parts by visual

d. Adjust the instrument air supply pressure to valve (pressure shall be refered to vendor data.) by air filter and regulator on valve.

e. Stroke valve from full open to fully closed position and vice versa. Adjust zero and span adjustment if required to obtain full open/full close at 4/20 mA limits.

f. Apply 5 points calibration check on I/P converters with corresponding to output pressure and valve position up scale and down scale. g. Check solenoid function and fail position, if any.

• Loss of air supply: if air supply isn’t enough, stroke time shall be long and valve shall not be in operating position.

• Loss of control signal: if power supply isn’t enough to attract solenoid coil, valve shall not be operated.

h.Check position switch function with P&F contact amplifier, if any. i. Check position transmitter functions, if any.

j. Record all results in Control Valve Calibration Report.

k. If required, defined by P&ID, stroke time shall also be verified. 6.12 On-Off Valves Function Test

6.12.1 Test Equipment a. Nitrogen cylinder. b. 24VDC power supplier c. Digital Multi meter.

d. P&F amplifier for proximity switch 6.12.2 Calibration Procedure

e. Check and confirm on-off valve air supply required and valve positioner and accessories data against manufacturer’s data sheet. f. Check On-off valve damaged parts by visual.

g. Adjust the instrument air supply to valve (pressure shall be refered to vendor data.) by air filter and regulator on valve.

h. Stroke valve from full open to fully closed position and vice versa and record stoke time.

(9)

i. Check solenoid function and fail position.

• Loss of air supply: if air supply isn’t enough, stroking time shall be long and valve shall not be in operating position.

• Loss of control signal: if power supply isn’t enough to attract solenoid coil, valve shall not be operated.

j. Check position switch function with P&F contact amplifier. k. Record all results in On-offl Valve Calibration Report. 6.13 Pressure Safety Valves (By Air)

6.13.1 Test Equipment a. Test Gauge. b. Air Regulator.

c. Test Bench c/w Manifold. 6.13.2 Calibration Procedure

a. Check the manufacturer’s data/instrument nameplate against CLIENT Specifications.

b. Connect up pressure relief valve.

c. Check the manufacturer’s seal for setting.

d. Hook-up Nitrogen or compress air cylinder to test manifold.

e. Adjust pressure via regulator. Gradually increase pressure until the pressure relief valves “pop”. Note: Reading on the test gauge.

f. Ensure the reset value within the tolerance. Reset value shall be recorded.

g. DO NOT attempt to remove “Manufacturer’s Seal” or attempt to adjust setting.

h. Compile all results in “SAFETY RELIEF VALVE”.

Air Compres

sor

Manifold

No.1 Manifold No.2

Test Gauge 1 Test Gauge 1 Water Containe r Release Point Drain Drain PSV

(10)

Figure 25: TYPICAL TEST SET-UP FOR PRESSURE RELIEF VALVE 6.14 Pressure Safety Valves (By Liquid)

6.14.1 Test Equipment a. Test Gauge. b. Regulator.

c. Test Bench c/w Manifold.

d. Pump.

6.14.2 Calibration Procedure

a. Check the manufacturer’s data/instrument nameplate against CLIENT Specifications.

b. Connect up pressure relief valve

c. Check the manufacturer’s seal for setting.

d. Hook-up Pump and Liquid Source to test manifold.

e. Adjust pressure via regulator. Gradually increase pressure until the pressure relief valves “pop”. Note: Reading on the test gauge.

f. Ensure the reset value within the tolerance. Reset value shall be recorded.

g. DO NOT attempt to remove “Manufacturer’s Seal” or attempt to adjust setting.

h. Compile all results in “SAFETY RELIEF VALVE”.

Figure 26 ITEM DESCRIPTION 1 Air Regulator 4 3 5 1 2

(11)

2 Test Gauge

3 Test Bench with Manifold

4 Valve

5 Relief Valve/Safety Valve under Testing

OTHERS INSTRUMENTS

The following instruments will not be tested in the workshop due to safety reason and the unavailability of the required test equipment and facilities. However, they have to be checked by visual check and need to be calibrated on-line during Commisioning phase.

• Smart electronic type transmitters shall be functionally tested by using a HART COMMUNICATOR to confirm the device smartness and data population.

• Factory Test Certificates shall be reviewed as part of visual check to confirm it’s validity.

• Site Calibration and commissioning procedure for these particular instruments shall be available and be used as mandatory requirement for site works.

Vortex Flow Meter

Calibration and tested in factory. Visual check only.

Coriolis Mass Flow Meter

Rotameters

(12)

PD Meter

Chromatographs Analyzer

Calibration and tested by vendor supervisor at site. Visual check only.

Moisture Analyzer

Calibration and tested by supervisor at site. Visual check only.

Conductivity Analyzer

Gas Detectors

Radiation Level Switch/Transmitter

Visual / Audible Alarm Devices Calibration and tested in factory. Visual check only.

Level Gauge

Tested in factory. Visual check only. Load Cell

(13)

Calibration and test will be done after installation. Visual check only.

Radar Type Level Transmitter

Vibration Level Switch Tested by Vendor. Visual check only. Venturi Tube, Annubar

Tested by Vendor. Visual check only. Integral Orifice Transmitter

Appendix-1.

Instrument Apparatus for Calibration and Test

No Description Model Accuracy Range Make

1 Air Pressure Calibrator DPI 610 0.025%FS -1 to 20bar Druck 2 Oil Pressure Calibrator DPI 610 _0.025%FS 0 – 135 bar With

Ext. Sensor 700bar Druck 3 Oil Pressure Calibrator _{DPI 615} _0.025%FS 0 to 400bar _Druck 4 Air Pressure Calibrator DPI 603 0.075% FS -1 to 20bar Druck 5 Air Pressure Calibrator DPI 610 0.075% FS -1 to 2bar Druck 6 Hand held Pressure

Calibrator

IS33-36/3000PSI 0.05%FS 0 - 3000PSI CRYSTAL Eng 7 Multifunction Calibrator MC5/MC5IS 0.025%FS -1 to 700bar Beameax 8 Documenting Calibrator Fluke 726 0.01%Rdg mA, mV, RTD, TC Fluke

(14)

9 Documenting Calibrator Fluke 741B 0.01%Rdg mA, mV, RTD, TC Fluke 10 Documenting Calibrator Fluke 743B 0.01%Rdg mA, mV, RTD, TC Fluke 11 Multifunction Calibrator Fluke 725 0.01%Rdg mA, mV, RTD, TC Fluke 12 Loop Milliamp

Calibrator UPS.IS 0.01%Rdg mA Druck

13 Multi-meter Fluke 87II 0.03%Rdg mA, A, mA, V,

Ohm, Hz Fluke

14 Hart Communicator 275 N/A communication Hart

15 Hart Communicator 375 N/A communication Hart

16 Unomat Calibrator TRX -IS 0.01%Rdg mA, mV, RTD, TC Druck 17 Dry -Well Calibrator DBC150TC 0.1o_C _{-45 to 150}o_C _Druck

18 Dry -Well Calibrator ₉₀₁₁ 0.10oC

0.15o_C -45 to 150oC_{50 to 670oC} Hart

19 Dry -Well Calibrator 9170 0.15o_C _{-45 to 140}o_C _Hart

20 Dry -Well Calibrator 9173 0.35o_C _{50 to 650}o_C _Hart

Appendix-2.

Quality Control Form (QCF) List

QCF-I002 Instrument Unpacking Inspection QCF-I003B Instrument Transmitter Calibration QCF-I004B Pressure Gauge Calibration

QCF-I004C Diffrential Pressure Gauge Calibration QCF-I005B Temperature Gauge Calibration

QCF-I005C Temperature Element (RTD) Inspection QCF-I006B Orifice Plate and Restriction Orifice Control QCF-I014 Pneumatic Control Valve Calibration

QCF-I015 On-Off Valve Function Test