Standard Operating Procedure for Operation and Calibration of Viscometer
1.0 Purpose:
To lay down a procedure for Operation and Calibration of Viscometer.
2.0 Scope:
The scope of this SOP is applicable for Operation and Calibration of Viscometer, Make – Brookfield, Model – DV-II+ Pro.
3.0 Responsibility:
QC Personnel: To Operate, Clean and Calibrate Viscometer, To Prepare the Calibration Report and Certificate of Analysis.
Lab QA Reviewer: To Check the Calibration Report and Certificate of Analysis.
Section Head QC / Designee: To Monitor the Activity.
Head-QC / Designee: To Approve the Calibration Report and Certificate of Analysis, To Monitor the Activity.
4.0 Definitions:
NA
5.0 Procedure:
5.1 Use a certified Viscosity Standard Fluid for Calibration.
5.2 The Brookfield Viscosity standard fluid should be replaced annually.
5.3 Set the level of the instrument properly.
5.4 Do not use the instrument after the due date of calibration.
5.5 Maintenance/Repairs: If the instrument does not comply with the requirement/acceptance criteria, it should be labelled as “OUT OF CALIBRATION”. The instrument shall be repaired/serviced and recalibrated as per the Calibration SOP.
5.6 Ensure that the instrument is within the validity period of calibration.
5.7 Handle the spindle carefully.
5.8 Operation:
5.8.1 Turn the power switch to the “ON” position.
5.8.2 After a few seconds, a screen appears indicating the version of the operating firmware.
5.8.3 After a short time, the display will clear and display, “REMOVE SPINDLE PRESS ANY KEY”.
5.8.4 After removing the spindle and pressing any key, the DV-II + Pro begins its auto zeroing and the screen will flash “Auto zeroing”.
5.8.5 After approximately 15 seconds, the display shows the screen, “REPLACE SPINDLE PRESS ANY KEY”.
5.8.6 Pressing any key at this point results in a change in display on the screen.
5.8.7 Pressing the select spindle key will display the currently selected spindle code instead of temperature and cause the character S to begin to blink. It will blink for about three seconds. If either the “UP” or “DOWN” arrow keys are pressed (while S is blinking), it will change the two-character spindle value.
5.8.8 When the desired spindle code is displayed, release the ARROW key to halt further scrolling.
5.8.9 To select a viscometer speed, first press either the “UP” or “Down” arrow keys which will cause the area to the right of RPM to display the currently selected speed.
5.8.10 When the required speed is displayed, release the ARROW key to halt further scrolling.
5.8.11 Pressing the MOTOR “ON / OFF / ESCAPE” key stops viscometer spindle rotation.
5.9 Making Viscosity Measurement:
5.9.1 Mount the Quardleg on the DV-II + Pro Viscometer and insert it into a container.
5.9.2 Insert and center spindle in test material until fluid’s level is at immersion groove on spindle’s shaft.
5.9.3 The process of selecting a spindle and speed for an unknown fluid is normally trial and error; an appropriate selection will result in measurements made between 10 -100 on instrument’s % torque scale.
5.9.4 Viscosity range is inversely proportional to size of spindle.
5.9.5 Viscosity range is inversely proportional to rotational speed.
5.9.6 Turn “ON” motor to allow time for indicated reading to stabilize and record values.
5.9.7 Press MOTOR “ON/OFF” key and turn motor “OFF”.
5.9.8 Clean and dry spindle using tissue paper.
5.10 Calibration Procedure:
5.10.1 Operate the Instrument as per Operating Procedure as per above steps.
5.10.2 Switch “ON” the Mains.
5.10.3 Check the level of Instrument. If not, set the Level of Instrument.
5.10.4 Calibrate with Brookfield Viscosity Standard Fluid (5, 100, 1000 cP).
5.10.5 Place the Brookfield Viscosity Standard Fluid in to the proper container.
5.10.6 Lower the DV-II + Pro into measurement position.
5.10.7 Select the Spindle (Spindle No. 61) and Speed.
5.10.8 Attach the Spindle to the Viscometer. If you are using a disk-shaped spindle, avoid trapping air bubbles beneath the disk by first immersing the spindle at angle, and then connecting it to the Viscometer.
5.10.9 The Brookfield Viscosity Standard Fluid, together with the spindle, should be immersed in the bath for a minimum of 1 hour, stirring the fluid periodically, prior to taking measurement.
5.10.10 After 1 hour, check the temperature of the Brookfield Viscosity Standard Fluid with an accurate thermometer.
5.10.11 Start the motor, measure the Viscosity, and record the reading.
5.11 Cleaning:
5.11.1 Turn “OFF” the Mains of the Instrument while Cleaning.
5.11.2 After operation wash the spindle with water and wipe with dry clean cloth.
5.11.3 Ensure proper cleaning of Viscometer.
6.0 Acceptance Criteria:
Calibration: ± 1 % of Stated Value.
7.0 Frequency:
7.1 Operation: As and when required.
7.2 Cleaning: After every Operation as per defined procedure.
7.3 Calibration: Quarterly -5 days.
8.0 Format for recording:
8.1 Format for “Instrument Usage Logbook”.
