As a precision testing instrument for experiments, the digital viscometer requires correct maintenance methods during use to ensure the accuracy and stability of the digital viscometer's service life.
In this article, taking Nirun DV-79 viscometer as an example, we will share in detail ten points that need to be paid attention to when maintaining the viscometer.
( 1 ) Be careful when loading and unloading the connecting rod at the coaxial end of the motor . Do not use too much force when screwing the M3 screw, and do not apply lateral force to the rotor hook to avoid bending the hook.
(2) The connecting rod at the coaxial end of the motor and the connecting rod should be kept clean, otherwise it will affect the shaking degree of the rotor.
(3) After replacing the rotor, please input the new rotor number in time. After each use, the replaced rotor should be cleaned in time (wipe it clean , including the inside of the rotor and the U -shaped spring hanging ring inside the rotor can be pulled out for cleaning , and the U-shaped spring hanging ring can be inserted into the U- shaped spring hanging ring to be reused ) and put back into the rotor frame. Never leave the rotor on the instrument for cleaning.
(4) When changing the liquid to be tested, please clean it in time (wipe it clean, including the inside of the rotor and the U-shaped spring hanging ring of the rotor can be pulled out for cleaning, insert the U-shaped spring hanging ring to reuse) the rotor and the test container , to avoid measurement errors caused by the confusion of the measured liquid.
(5) The instrument and the rotor are one-to-one matching, please do not confuse several instruments and rotors.
(6) Please do not disassemble and adjust the instrument parts at will.
(7) When moving and transporting the instrument, just remove the main unit and put it in an aluminum alloy box.
(8) After installing the rotor, please do not rotate it for a long time without liquid, so as not to damage the bearing and rotor.
(9) Many of the suspensions, emulsions, polymers and other high-viscosity liquids are "non-Newtonian liquids", and their viscosity values change with changes in conditions such as shear speed and time . The inconsistency of the measured results under the speed and time is normal and not an instrument error. For the determination of non-Newtonian liquids, the rotor, rotational speed and time should generally be specified.
(10) Doing the following points will help to measure more accurate values:
• Accurately control the temperature of the measured liquid.
• Immerse the rotor in the liquid to be measured for a long enough time to make the temperature of both the same.
• Maintain liquid homogeneity.
• Place the rotor in the center of the container to ensure coaxial state during measurement.
• Keep the rotor clean and free from vibration.
• When the measurement of high rotation speed changes to low rotation speed immediately, the machine should be turned off, or the measurement time at low rotation speed should be controlled a little longer , so as to overcome the error caused by the rotational inertia of the liquid.
• When measuring low viscosity, choose A spindle, and when measuring high viscosity, choose G spindle.
• When measuring viscosity at low speed, the measurement time is relatively longer.
