CALIBRATION OF MANOMETER (INCLINED) MAGNEHELIC GAUGES

1.0    PURPOSE :
    
To describe a standard operating procedure for the calibration of Manometer (Inclined) / Magnehelic gauge.
    
2.0    SCOPE:
    
    The standard operating procedure describes in detail the method for the calibration of Manometer (Inclined) / Magnehelic gauge used in the air handling units and clean room areas.
    
3.0    RESPONSIBILITY:
    
    The  responsibility of  calibrating the Manometer (Inclined) / Magnehelic gauge lies with the staff of rank not lower than the supervisor of maintenance department. 
    
    The responsibility of preparation, review and approval of the standard operating procedure lies with the Manager - Maintenance, General  Manager (Production) and Head of QAD respectively.
    
4.0    METHOD:
    
4.1    Check the atmospheric/ room temperature.  It should be 27 ± 5° C.
    
4.2    Check the Manometer to be calibrated for any physical damages.
    
4.3    With the help of spirit level, keep the Manometer (Inclined) / Magnehelic gauge to the level.
    
4.4    Fill the Manometer liquid from the lower end (Highest measuring digit end) using the funnel till the zero level mark.  Incase it is slightly more/less than the zero level mark adjust it with the knob provided for moving the scale. Adjust the indicator pointer exactly to zero mark with the help of screw provided in case of magnehelic gauge. 
    
    
4.5    Connect the master Manometer, which is calibrated and traceability with National Physical Laboratories. or their authorised Laboratories, and the Manometer to be calibrated to the sucking bulb.
    
4.6    Check and compare the readings of master Manometer and Manometer (Inclined) / Magnehelic gauge to be tested to the maximum scale range with the help of sucking bulb.  Record the results in Annexure-I.
    
4.7    The acceptance criteria for the calibration of Manometer (Inclined) / Magnehelic gauge is as follows.
    
4.7.1

    Acceptance criteria:

The resolution of gauge shall be considered as acceptance criteria for that particular gauge.
?    If the gauge is graduated with 0.1 mm of wgp resolution, the acceptance criteria shall be 0.1 mm of wgp.
?    If the gauge is graduated with 0.2 mm of wgp resolution, the acceptance criteria shall be 0.2 mm of wgp.
?    If the gauge is graduated with 0.5 mm of wgp resolution, the acceptance criteria shall be 0.5 mm of wgp.
    
4.8    During the calibration, if the Manometer (Inclined) / Magnehelic gauge does not meet the acceptance criteria, service the Manometer, recalibrate by informing to the QAD and record the readings in Annexure-II. If it is not possible to repair the Manometer (Inclined) / Magnehelic gauge replace with new.
    
4.9    All the Manometer (Inclined) / Magnehelic gauges are calibrated by out side agency in the presence of maintenance department personal as per the procedure and rectification of the Manometer (Inclined) / Magnehelic gauge recalibration shall be carried out by maintenance department.
    
    
4.10

    If the Manometer (Inclined) / Magnehelic gauge is replaced with new within the calibration due date, It should be recalibrated and recorded as per the Annexure-I and also entered in the history card of the Manometer (Inclined) / Magnehelic gauge.
    
4.11    Frequency: Manometer (Inclined) / Magnehelic gauge calibration should be performed once in three months ± 2 days and display with the following particulars.

5.0    RECORDING:
    
    The responsibility of recording the calibration readings as per Annexures lies with the staff of rank not lower than supervisor of maintenance department.

Manometer, magnehelic gauges, engineering