by - Objective
To lay down a procedure for operation and calibration of viscometer. It is used to determine the viscosity of solution / suspension / liquids.
- Scope
This SOP is applicable for operation and calibration of viscometer (Make: BROOKFIELD; Model: DV-I+)in Quality Control.
- Responsibility
QC Chemist / Officer : Follow the procedure and maintain record as applicable.
- Accountability
Head Quality Control : System Compliance
- Procedure:
- Operation:
- Ensure that equipment is clean.
- Check the level of instrument with the help of spirit level on the top of the Viscometer, and if required set level with help of three screw on triangle bottom.
- Check the connection of electric supply behind thermister plug with temperature probe (socket) on posterior panel.
- Clean the spindle which you have to use and maintain the temperature of liquid as required.
- Put ON the electric supply and switch on the switch of instrument at the posterior left.
- Wait for some time; screen will instruct for PRESS ANY KEY. Press any key.
- Screen will show %, spindle code, RPM, Viscosity (cps) and Torque (%).
- For selecting the spindle code (as per requirement) press buttons SELECT SPINDLE . Blowing start for change in press UP arrow and DOWN arrow and when desired number comes on screen, again press SELECT SPINDLE. Blowing will stop.
- For setting RPM ( as per required) press SET SPEED , set number by using up and down arrow, again press SET SPEED.
- Fit the spindle (as per requirement) in horizontal screw pin by clock wise rotation carefully (up to spindle mark).
- Move the spindle up with screw on horizontal stand and place beaker having liquid below the spindle down for immersing the spindle head in liquid completely (up to spindle mark).
- Press the red switch MOTOR ON/OFF.
- Spindle will start rotating; press the SELECT DISPLAY again and again screen will express the reading %, mPas, SS, SR, reading one by one. Note the reading as per requirement.
- After completion of work clean the spindle and place it properly.
- Switch OFF the equipment.
- Enter the details in Instrument log).
- Calibration :
- Calibration of viscosity:
- Operation:
Operate the viscometer.
- Use the spindle No 1,
and Viscosity Standard as per given below table.
- Check the temperature of solution and it should be between 25 ± 1°C.
- Take average of three readings.
| S. No. | Spindle No | RPM | Viscosity of Standard Solution (cps) | Tolerance (cps) |
| 1 | 1 | 6 | As per Standard value | ±2% |
| 2 | 1 | 50 | As per Standard value | ±2% |
| 3 | 1 | 100 | As per Standard value | ±2% |
- Enter the details in Annexure I.
- Prepare the calibration tagand affix it on the equipment.
- Enclose the old calibration tag with the record and don’t throw it.
- Calibration of RPM :
- RPM calibration shall be done by external agency for 6RPM, 50 RPM, and 100 RPM.
- Acceptance criteria: 6 RPM ± 1RPM , 50 RPM ± 1RPM ,100 RPM± 2RPM
- If the variation is not within the specified tolerance limits:
- Label the equipment with a tag, “OUT OF CALIBRATION”.
- Inform to the Department Head.
- Do not use equipment until all errors are rectified. After rectification, again calibrate the equipment & record the observation.
- Frequency: Calibration of Viscosity: Monthly ± 3 days.
Calibration of RPM (Outside calibration agency) : 6 Months ± 15days.
- Important:
- Liquid must be free from air bubble.
- Spindle must be in middle of the liquid.
- Check carefully the Temperature, the Spindle code and the RPM.
- If any problem exists in the equipment inform to the service engineer.
- For more details refer instruction manual
- Annexure(s)
NA
- Reference(s)
Manufacturer manual
- Glossary
SOP : Standard Operating Procedure.
QC : Quality Control
QA : Quality Assurance
Cps : centipoises
°C : Degree Centigrade
- Revision History
| Rev. No. | Details of changes | Reason for change |
