Viscosity Standards and Reference Fluids Information
Viscosity standards and reference fluids assist in verifying or calibrating rheometers and viscometers. These substances establish traceability of the instruments to national and international standards. They provide certified values for parameters such as dynamic and kinematic viscosities, density and measurement uncertainties.
Viscosity measurement occurs in a comprehensive range of applications dealing with the quality and efficiency aspects of products. The primary function is offering a quick and accurate method for the assessment of factors crucial to performance. Standard activities include quality control, research and development and flow characterization. Such information is relevant at different stages of product design and manufacturing.
The Value of Measuring Rheology and Viscosity
Measuring viscosity provides information for predicting the behavior of various materials, including the impact of formulation changes, processing and aging. Rheological data is gathered when simple thickness properties are insufficient. It is effective in quality control checks by ensuring consistency of each batch of materials. Flow behavior analysis is an alternative means of evaluating a product’s consistency and quality. Determining the rheological features of a fluid helps in designing the pumping and piping mechanisms.
These parameters are essential in polymer synthesis. They enable the discovery of relative differences without the necessity of determining molecular weight. They facilitate the process of monitoring chemical reactions. In addition, rheological properties serve as quality checks throughout production. They enable analysis of chemical, mechanical and thermal activities as well as additive effects.
Viscometers and rheometers support a myriad of functions and features and perform both simple and complex measurement operations. Viscosity standards and reference fluids cover an extensive selection of types, including:
- General purpose silicone
- General purpose oil
- High-temperature silicone fluids
- CAP oil fluids
- R/S rheometer oil fluids
- Krebs viscometer oil fluids
Applicable categories of standards used in testing include:
- Low temperature
- Kinematic viscosity
- High viscosity
- Dynamic viscosity
Instruments that are subject to verification or calibration include:
Cone and plate viscometers
Rolling ball viscometers
Glass capillary viscometers
Cup and falling ball viscometers
Cold-cranking simulator viscometers (CCS)
How Viscosity Standards and Reference Fluids Work
Reference fluids are prepared at laboratories based on master viscometer and rheometer scales calibrated to specific standards such as ISO 17025, AST D2162 and BS188. Calibration of the substances involves measuring them across a broad spectrum of temperatures. Reference substances are replaced once a year or every two years to ensure optimum precision.
Viscosity or thickness parameters support a wide array of applications where fluid dynamics is important. All liquid substances possess some resistance to stress or shear, qualifying them as viscous. However, this term applies to fluids with higher viscosity than water. Certain materials are much thicker creating a solid appearance, as with tar or pitch. On the other hand, materials with lower viscosity are referred to as mobile.
Rheometers are employed instead of viscometers when it is difficult to assign a single value to the substance. Such instances demand the analysis of further parameters. When performing the assessment, strict temperature control is necessary to avoid major variation in the readings.
Viscosity standards and reference materials function in a broad scope of processes, including: Manufacturing Quality Control/Quality Assurance Food preparation Pipelines Polymer synthesis Chemistry Selecting Viscosity Standards and Reference Fluids Viscosity standards and reference fluids are employed in a diverse set of processes and cover a multitude of categories with many distinct uses. Check manufacturer’s specifications to determine if a particular product is suitable for the intended use.
Specifications and Standards
Many industry groups throughout the world define the standards and specifications related to the reference materials. Some applicable standards include: