- OBJECTIVE : To lay down a procedure for Calibration of Disintegration test apparatus.
- SCOPE : This Standard Operating Procedure (SOP) is applicable to DT apparatus placed in Quality Control.
- RESPONSIBILITY:IPQA / Production Executive / Officer
- ACCOUNTABILITY : Head –Quality Assurance
- Check the water level in the water bath.
- Fill the water in the beakers up to required mark.
- Operate the DT (Disintegration Test) machine as per SOP.
- The following parameters shall be verified under the calibration of D T Apparatus.
- Number of cycles per minute.
- Stroke length of basket assembly.
- Aperture of wire mesh & Diameter of wire mesh.
- NUMBER OF CYCLES PER MINUTE
- Adjust if necessary the volume of the water in the beakers such that the wire mesh at the highest point is at least 15 mm below the surface of water and at its lowest point is at least 25mm above the bottom of beaker.
- Count the cycles of up & down of the basket assembly per minute using a calibrated stop watch.
- Repeat the same procedure thrice. Record the number of cycles.
- Acceptance criteria – Cycles per minutes should be 29 to 32.
- TEMPERATURE CALIBRATION
- Set the temperature at 37 °C.
- Check the temperature of water in the beaker and wait till display shows temperature with in 37°c ± 0.5°c.
- Measure the temperature of water in the beaker using calibrated thermometer and record the reading of both thermometer value and instrument-displayed value.
- Acceptance criteria – Instrument displayed value and calibrated thermometer value should match by ± 0.5°C and temperature value should be with in 37 ±0.5°C.
- Check the instrument timer for accuracy at 15,30 and 60 minutes respectively against a calibrated Stop watch.
- Enter observation in the format as per Annexure I
- Acceptance criteria – time variation should not be more than ± 20 seconds between Instrument timer and calibrated timer.
WIRE MESH CALIBRATION
- Use calibrated Vernier caliper for measuring the aperture size.
- Check & ensure that there is no loose end in any of the tube.
- Check randomly at least one aperture from each tube and record the observation.
- Check the diameter of wire selected at least one number from all the tubes and record the observation.
STROKE LENGTH OF BASKET ASSEMBLY
- Unscrew the basket A from the bottom
- Remove the basket bottom plate and cover.
- Remove one tube and replace the bottom cover and screw it again.
- Engage the basket to the basket holder.
- Insert the measuring scale or Vernier into the disc from where the tubing is removed.
Note: the scale bottom should touch the bottom of the beaker.
- Start the instrument and press RUN / HALT key of basket A from front panel
- Measure the lower most position from bottom of beaker and top most position of basket holder.
- Record the distance in mm.
- Repeat the above steps with Basket assembly B.
- Acceptance criteria – stroke length should be 55 ± 2 mm.
- Fill the details of the calibration status in the label pasted on the Instrument.
- Report any discrepancy observed during calibration to Manager QA/QC and notify the defect to engineering department or Service Engineer of the instrument. Affix an Under Maintenance label on the instrument.
Frequency of calibration
- Calibrate the apparatus quarterly and after each maintenance job.
|1||No. of Cycles/min.||Visually/Calibrated stop watch||29-32 Cycles/min||QUATERLY|
|2||Temperature||Calibrated Thermometer||37± 0.5°C|
|3||Time||Calibrated Stopwatch||±20 sec / 10min|
|4||Aperture of wire mesh||Calibrated Vernier caliper||1.80 to 2.20 mm|
|5||Diameter of wire of wire mesh||Calibrated Vernier caliper||0.60 – 0.65 mm|
|6||Stroke length of basket assembly||Calibrated Vernier caliper/ scale [6 inch]||55 ± 2 mm|