Standard Operating Procedure (SOP) for Operation and Calibration of Brookfield make Viscometer used to determine the viscosity of solution / suspension / liquids in Quality Control department.
Viscometer (Brookfield) – Operation and Calibration Procedure
1.0 Objective :
-
- To lay down a procedure for operation and calibration of viscometer. It is used to determine the viscosity of solution / suspension / liquids.
2.0 Scope :
-
- This SOP is applicable for operation and calibration of viscometer (Make: BROOKFIELD; Model : DV-I+) in Quality Control.
- This SOP is applicable for operation and calibration of viscometer (Make: BROOKFIELD; Model : DV-I+) in Quality Control.
3.0 Procedure – Viscometer:
-
-
What is Viscosity ?
-
-
- Viscosity is a measure of a fluid’s resistance to flow.
-
- It describes the internal friction of a moving fluid.
-
- A fluid with large viscosity resists motion because its molecular makeup gives it a lot of internal friction.
-
- A fluid with low viscosity flows easily because its molecular makeup results in very little friction when it is in motion.
-
- Gases also have viscosity, although it is a little harder to notice it in ordinary circumstances.
-
Operation Procedure for Viscometer:
-
- 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 thermistor 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 Procedure of Viscometer :
-
-
Calibration of viscosity:
-
-
- Operate the viscometer as per SOP.
-
- 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 tag and 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 of Viscometer Calibration:
-
-
- Calibration of Viscosity: Monthly ± 3 days.
-
- Calibration of RPM : 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-I : Calibration Record of Viscometer
Make : …………………. Eq. No. : …………………… Model No. : ……………….
Viscosity: Calibration Frequency : Monthly ± 3 days
| Sr. No. | Spindle No. | RPM | Actual viscosity of Standard Solution (cps) | Observed Viscosity | Average | Tolerance (cps) |
| 1 | 1 | 6 | ±2% | |||
| 2 | 1 | 50 | ±2% | |||
| 3 | 1 | 100 | ±2% | |||
Calibration done on: ………………… Next calibration due on : ……………………….
Spindle RPM: Calibration Frequency : 6 Months ± 15 days
Calibration done on : ……………………….. Done by : ………………………
Calibration report No. : ……………………… Next calibration due on : ………………………
Remarks: The observed values comply / does not comply the acceptance criteria and the equipment can be / cannot be used for routine analysis.
Reference(s)
Manufacturer manual
SOP : Status Labeling
SOP : Filling of Instrument Log
Glossary
SOP : Standard Operating Procedure.
QC : Quality Control
QA : Quality Assurance
Cps : centipoises
°C : Degree Centigrade