Viscosity parameters are crucial for a number of materials including fuels, lubricants, medicines, oils, and paints. Ensuring that a material substance possesses the right amount of viscosity allows it to function properly. For oils and lubricants, inconsistent viscosity parameters coupled with material degradation can result in expensive equipment failures.1
Due to the fact material viscosity has such importance across several applications, industries, and products, the primary goal is to find accurate and dependable ways of measuring it. There are several tests and a variety of equipment types that are used for assessing materials, including viscometers and rheometers.2
Finding the appropriate test type well-suited to any given material forms part of the challenge when conducting best-practice viscosity measurements, but knowing how to assess whether the equipment is producing accurate meaning data is another question.
The application of high-quality viscosity standards ensures the capture of optimal viscosity measurements. Such standards offer both a straightforward and highly efficient way to calibrate and verify instruments to guarantee viscosity measurements make the grade.
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What are Viscosity Standards?
A viscosity standard is a reference material developed for precision calibration and the verification of viscosity instruments. When applying viscosity standards, the measuring equipment should be able to deliver viscosity data corresponding to certified values at a given temperature, accounting for the criteria of any test method’s precision and acceptability.
Certified viscosity standards offer traceability with regard to their calibration, in addition to a quoted ‘Expanded Uncertainty’ relative to the certified values on the accompanying certificate.
Traceability and Uncertainty are essential parameters for all reference materials to meet compliance protocols across a range of international standards and methodologies.
Specialist companies, like LGC Standards, have the expertise and experience that allow them to offer a variety of standard types to make sure the right reference standard is used with the right measurement type, an essential requirement.
Examples of LGC Standards’ extensive range of viscosity standards ready for supply and their applications are detailed below.
How Can Standards Help You?
Standards are a key component of any measurement, as holding known samples with known certified values is the only viable solution that can confirm if an instrument is measuring as it should.
One of the significant benefits of using standards is that as well as improving confidence and offering assurances in measurement quality, it also boosts overall efficiency.
Incorporating standards into measurement procedures and protocols means that it is relatively straightforward if there are any immediate problems, whether that be in relation to instrumentation, methodology, or operator performance. This means that there is no need for unnecessary troubleshooting saving valuable time and resources.
Purchasing certified reference standards with complete traceability from expert partners like LGC paves the way toward achieving maximum efficiency and getting the most out of reference standards.
Types of Viscosity Standards
LGC Standards can provide a wide range of certified viscosity standards suitable for calibrating and verifying auto viscometers, glass capillary viscometers, rotational viscometers, flow cups, and other viscosity measuring equipment.
All viscosity standards can be traced back to the primary standard of pure water, which has a Kinematic Viscosity of 1.0034 mm2/s at 20 °C, which is in keeping with those standards used by national metrology laboratories such as NIST and national standard bodies such as ASTM, IP, and ISO.
All certifications comply with ISO 17025 and ISO 17034 accreditations. Examples of the viscosity standards available are provided below, along with their applications. Please note this list is not exhaustive:
- General purpose viscosity standards are certified at temperatures between 20 and 100 °C in line with ASTM D2162, the primary method for the certification and basic calibration of oil-based viscosity standards. This offers the customer a broad set of certified viscosity values across the specified temperature range, suitable for use in various applications and industries.
- Cold cranking simulator (CCS) viscosity standards are manufactured and certified for use with ASTM D5293, standard test method for apparent viscosity of engine oils and base stocks between -10 °C and -35 °C using cold-cranking simulator. They are also appropriate for use with other low temperature test requirements.3
- Low temperature viscosity standards certified at a range of temperatures spanning 0 to -40 °C can be applied in many low temperature applications. While not restricted to the petroleum industry, prime application examples include certifying the viscosity of aviation fuel at -20 °C and the viscosity of lubricants at low temperatures by rotational viscometer.
- High temperature viscosity standards are certified at temperature ranges spanning 100 and 150 °C. These are intended for applications where verifying viscometer performance is essential at such temperatures.
- Rotational viscosity standards are available in two matrices which are intended for the calibration and verification of rotational viscometers. They can be supplied as a silicone fluid matrix (certified at 20 and 25 °C) or as an oil matrix (certified between 20 and 25 °C, at 0.5 °C intervals).
- Medical viscosity standards are certified at 25 and 37 °C for use in clinical viscometers including those used for measuring the viscosity of blood plasma, as well as for application in other pharmaceutical areas.4
- Cone and Plate/Flow cup viscosity standards are certified at temperatures ranging between 20 and 25 °C and are appropriate for use with viscometers typically deployed in the paints, coatings, and varnish industries.
LGC Standards
Industry leader LGC Standards has been leading the development and manufacture of certified reference materials for industrial applications for over three decades. LGC Standards is an ideal partner to supply high-quality reference materials to support your business goals. Using high-quality, certified reference materials, you are better positioned to achieve operational savings and improve quality control in all industrial processes and applications.
References and Further Reading
- Wakiru, J. M., Pintelon, L., Muchiri, P. N., & Chemweno, P. K. (2019). A review on lubricant condition monitoring information analysis for maintenance decision support. Mechanical Systems and Signal Processing, 118, 108–132. https://doi.org/10.1016/j.ymssp.2018.08.039
- Gupta, S., Wang, W. S., & Vanapalli, S. A. (2016). Microfluidic viscometers for shear rheology of complex fluids and biofluids. Biomicrofluidics, 10(4). https://doi.org/10.1063/1.4955123
- Myshkin, N. K., Markova, L. V., Myshkin, N. K., & Markova, L. V. (2018). Oil viscosity monitoring. On-line Condition Monitoring in Industrial Lubrication and Tribology, 31-59. https://doi.org/10.1007/978-3-319-61134-1_2
- Marapureddy, S. G., & Thareja, P. (2020). Structure and rheology of hydrogels: applications in drug delivery. Biointerface Engineering: Prospects in Medical Diagnostics and Drug Delivery, 75-99. https://doi.org/10.1007/978-981-15-4790-4_4
This information has been sourced, reviewed and adapted from materials provided by LGC Limited
For more information on this source, please visit LGC Limited