NUMBERING AND CALIBRATION OF WATER FLOW METERS

1.0    PURPOSE:
        
To describe a standard operating procedure for numbering and calibration of water flow meters.
    
2.0    SCOPE:
    
    The standard operating  procedure describes  in detail  the  method  for the numbering and calibration of water flow meters using for soft water at various locations in the plant.
    
3.0    RESPONSIBILITY:
    
    The responsibility of numbering the water flow meters lies with the staff of rank  not  lower than the Maintenance Engineer of maintenance department and the responsibility of calibration lies with the staff of rank not lower than technician of Maintenance department.         
    
    The  responsibility of preparing, reviewing and approving  the  standard     operating    procedure lies  with  the   Manager  -  Maintenance, Head of  Production  and Head of QAD respectively.
    
4.0    METHOD:
    
4.1    Identification nos. for the flow meters shall be given as FM xxx where FM stands for Flow Meter and xxx stands for serial no. of the flow meter i.e. 001, 002 etc.
    
4.2    Identification no. shall be displayed on flow meter with letter/number punch.
    
4.3    Note down the initial reading of the water flow meter.
    
4.4    Open the valve and collect 10 L of water into the carboy.
    
4.5    Ensure 10 L of water collected through water flow meter. 
    
4.6    Note down the final reading of the water flow meter.
    
4.7    Weigh the collected water with weighing machine and record the weight.
    
4.8    Repeat the steps 4.3 to 4.7 for 50 L and 100 L collection of water through water flow meter.
    
4.9    Compare the volume of water collected through water flow meter with corresponding weight measured on weighing machine.
    
4.10    Find the difference between the flow meter reading and the corresponding weight displayed by the weighing machine, the difference and corresponding correction shall be recorded.
    
4.11    Record the calibration data in Annexure-I.
    
4.12    If the flow meter shows zero error a white coloured tag showing the status of flow meter shall be tied to the water flow meter.
    
4.13    Acceptance criteria: ± 5% of full scale division of the water flow meter.
    
4.14    If the flow meter shows an error within acceptance criteria a pink coloured tag showing the status and correction shall be tied to the flow meter. 
    
4.15    If the flow meter shows an error of beyond the acceptance criteria within the calibration due date, the production department who has identified the error will inform to the maintenance department by engineering requisition for recalibration.
    
4.16    Maintenance department will attend to rectify the problem as follows.
    
•        Disconnect the flow meter from the position and check for any foreign particles.
        
•        Clean the flow meter inner parts with jet of air.
        
•        Flush the inner parts with water.
    
4.17    Recalibrate the flow meter as per the steps 4.3 to 4.10 and record the recalibration data in Annexure-II.
    
4.18    Even after service by the maintenance department, the flow meter is not showing readings within the acceptance criteria it shall be repaired by outside service agency.
    
4.19    After service by the outside service agency the flow meter shall be recalibrated  and record the details in Annexure-II.
    
4.20    Even after the service by the outside agency, if the flow meter is not showing the readings within the acceptance criteria the flow meter shall be replaced with new water flow meter duly calibrated.
    
4.21    Apart from the recalibration, the calibration shall be followed as per the regular schedule.
    
4.22    Frequency: Calibration shall be carried out once in two months ± 2 days.
    
4.23    Calibration tag for flow meters shall have the following particulars.

Calibration of water, flow meters, engineering