Brookfield viscometer manual rvf

By continuing to use this site, you agree to our Privacy and Cookie policy. Laboratory Viscometers Brookfield has a reputation of being the world leader in viscosity measurements for over 80 years providing a variety of laboratory viscometers to suit a wide variety of applications. Keep Reading. The higher the torque calibration, the higher the measurement range. The viscosity measurement range for each torque calibration may be found in Appendix B.

The equivalent units of measurement in the SI system are calculated using the following conversions: Viscosity: Torque:. Please check to be sure that you have received all components, and that there is no damage. If you are missing any parts, please notify Brookfield Engineering or your local Brookfield agent immediately. Brookfield offers a complete line of refrigerated and non-refrigerated tap water cooling circulating water baths.

Cone CP is used in the illustrations. The water bath is on, set at the same test temperature that you will use when measuring the viscosity of your sample and is connected to the sample cup Figure A1. Allow enough time for the bath to reach the test temperature. The Viscometer speed knob should be set at 10 or 12 rpm with motor OFF. Remove the sample cup and attach the cone to the Viscometer Note: left hand threads , using the spindle wrench to hold the Viscometer shaft Figure A2.

Note: Lift up gently on the spindle wrench. Attach the sample cup and swing the clip under the cup to secure it in place. Take care to avoid hitting the cone with the cup Figure A3. Note: Do not add test sample during the gap setting procedure. Start the Viscometer running at 10 or 12 rpm.

If the display reading jumps to 0. Brookfield Engineering Laboratories, Inc. Turn the adjustment ring to the right counterclockwise as you look down on the instrument in small increments one or two divisions of the ring while watching the Viscometer dial Figure A5. Remember that you are trying to raise the cup so that the pin in the cone touches the pin in the cup.

You must wait at least 6 seconds between movements of the ring. Turn the adjustment ring until the display reading jumps from 0. The cup may have to be adjusted up and down several times before this deflection is satisfactorily reached. The LV series Viscometer will be the most sensitive. Index Mark. Turn the adjustment ring to the left clockwise as you look down on the instrument exactly the width of one division from the pencil mark you have just made.

This will separate the pins by 0. This is a very important step because if it is not done, the pins may touch constantly and may cause wear and damage to the cone, cup and instrument. The Viscometer is now mechanically set and ready for sample measurement Figure A7. Each of the five available cones has a specific sample volume, as shown in Table A1.

Note that the correct amount of sample fluid should cover the cone face and up over the edge less than 1mm as shown in Figure A8. The amount varies per cone spindle refer to Table A1. Notes: 1 The spindle must rotate at least 5 times before a viscosity reading is taken. Please contact Brookfield Engineering Laboratories or an authorized dealer if your calibration procedure requires more viscous standards.

Refer to Appendix B for viscosity ranges of cone spindles. Consult with Brookfield or an authorized dealer to determine which fluid is appropriate. Viscosity in poise is the ratio of shear stress to shear rate. Shear stress is related to the summation of torque T over the conical surface.

Cone CP 0. Cone CP 1 ml Sample When calibrating 2. RVF , 2, , 4, , 10, - 1,, 20, - 2,, 50, - 5,, , These variables may be related to the instrument viscometer , or the test fluid. Variables related to the test fluid deal with the rheological properties of the fluid, while instrument variables would include the viscometer design and the spindle geometry system utilized.

Rheological Properties Fluids have different rheological characteristics that can be described by viscometer measurements. We can then work with these fluids to suit our lab or process conditions. There are two categories of fluids: Newtonian. Therefore, these fluids will exhibit changes in viscosity with both changes in shear rate and the passage of time.

Time Independent Pseudoplastic. If you take viscometer readings from a low to a high RPM and then back to the low RPM, and the readings fall upon themselves, the material is time independent pseudoplastic and shear thinning. If you set a viscometer at a constant speed, recording cP values over time and find that the cP values decrease with time, the material is thixotropic. Viscometer Related Variables Most fluid viscosities are found to be non-Newtonian. They are Shear Rate dependent on the measurement conditions.

The specifications of the viscometer spindle and chamber geometry will affect the viscosity readings. If one reading is taken at 2. The faster the spindle speed, the higher the shear rate. The shear rate of a given measurement is determined by: the rotational speed of the spindle, the size and shape of the spindle, the size and shape of the container used, and therefore, the distance between the container wall and the spindle surface.

Viscosity standards are Newtonian, and therefore, have the same viscosity regardless of spindle speed or shear rate. Container size:. Inside Diameter: 3. The Viscometer should be set according to the operating instructions. The water bath should be stabilized at test temperature.

These fluids are pure silicone and are not subject to change over time. However, exposure to outside contaminants through normal use requires replacement on an annual basis. Contamination may occur by the introduction of solvent, standard of different viscosity or other foreign material.

Viscosity Standard Fluids may be stored under normal laboratory conditions. Disposal should be in accordance with state, local and federal regulations as specified on the material safety data sheet. We will issue duplicate copies of the Certificate of Calibration for any fluid within two years of the purchase date. Brookfield Viscosity Standard Fluids are reusable provided they are not contaminated.

Normal practice for usage in a ml beaker is to return the material from the beaker back into the bottle. If you are using a disk-shaped spindle, avoid trapping air bubbles beneath the disk by first immersing the spindle at an angle, and then connecting it to the Viscometer. Note: The spindle must rotate at least five 5 times before readings are taken.