ASTM D2270-24 PDF

Full title and description

ASTM D2270-24 — Standard Practice for Calculating Viscosity Index from Kinematic Viscosity at 40 °C and 100 °C. This practice defines the calculations, tables, and procedures used to determine the viscosity index (VI) — a single-number measure of the temperature dependence of kinematic viscosity — from kinematic viscosity measurements at 40 °C and 100 °C for petroleum products and related lubricants.

Abstract

This standard provides two calculation procedures (Procedure A and Procedure B) and tabulated data for deriving the viscosity index (VI) of oils and related petroleum products from measured kinematic viscosities at 40 °C and 100 °C. It explains applicability limits, required input test methods, and the mathematical relationships used to compute VI for products across typical viscosity ranges. The practice is intended for laboratory and quality-control use where a single metric for temperature sensitivity of viscosity is required.

General information

• Status: Active (current).
• Publication date: May 1, 2024 (ASTM D2270-24; ASTM store last updated May 13, 2024).
• Publisher: ASTM International.
• ICS / categories: 17.060 (Measurement of volume, mass, density, viscosity); Book of Standards volume 05.01 (Petroleum products, liquid fuels, and lubricants).
• Edition / version: D2270-24 (2024).
• Number of pages: 6.

Scope

The practice covers procedures for calculating viscosity index (VI) from kinematic viscosity values measured at 40 °C and 100 °C for lubricating oils and related petroleum products. It specifies two calculation procedures (A for VI ≤ 100 and B for VI ≥ 100), provides a tabulated reference applicable for kinematic viscosities at 100 °C between about 2 and 70 mm2/s (cSt), and gives equations for higher viscosities. The standard excludes products with kinematic viscosity at 100 °C below 2.0 mm2/s from its main table-based procedure and references methods for estimating VI when direct 40 °C/100 °C data are not available. It also cites required kinematic-viscosity test methods (for example ASTM D445 and D7042) and requires SI units for reporting.

Key topics and requirements

• Definition and significance of Viscosity Index (VI) as a measure of temperature dependence of kinematic viscosity.
• Two calculation procedures: Procedure A (VI up to and including 100) and Procedure B (VI 100 and greater).
• Tabulated reference values for use with kinematic viscosities at 100 °C between ~2 and 70 mm2/s (cSt); equations provided for viscosities above that range.
• Applicability limit: practice does not apply to products with kinematic viscosity less than 2.0 mm2/s at 100 °C for the primary table.
• Input requirements: accurate kinematic viscosity at 40 °C and 100 °C, determined using accepted test methods (e.g., ASTM D445, ASTM D7042, ISO 3104, IP 71).
• Reporting conventions: SI units (mm2/s or cSt), rounding and significant-figure guidance consistent with common laboratory practice.
• Cross-references to related test methods (D341 for estimation from other temperatures; D445/D7042 for kinematic viscosity measurement).

Typical use and users

Used in chemical and petroleum laboratories, lubricant manufacturers, formulation and quality-control departments, test houses, and by OEMs and standards bodies to characterize and report the temperature dependence of viscosity. Typical users include analytical chemists, R&D formulators, QC technicians, lubricant specification writers, and certification/test laboratories performing routine VI calculations or reporting VI in product data sheets.

Related standards

Commonly referenced and complementary standards include ASTM D445 (Kinematic Viscosity of Transparent and Opaque Liquids), ASTM D7042 (Dynamic Viscosity and Density by Stabinger Viscometer), ASTM D341 (Viscosity-Temperature Charts), ISO 3104, ISO 2909, IP 71, and other ASTM D-series petroleum and lubricant test methods. D2270 is maintained within ASTM Committee D02 (petroleum products and lubricants) and is used alongside other petroleum test methods and specifications.

Keywords

viscosity index; VI; kinematic viscosity; cSt; 40 °C; 100 °C; lubricating oil; petroleum products; viscosity-temperature dependence; ASTMD2270; calculation; Procedure A; Procedure B.

FAQ

Q: What is this standard?

A: ASTM D2270-24 is the ASTM standard practice that defines how to calculate the viscosity index (VI) of petroleum products and lubricants from measured kinematic viscosities at 40 °C and 100 °C.

Q: What does it cover?

A: It covers the calculation procedures (two procedures depending on VI range), tabulated reference data for common viscosity ranges, equations for high-viscosity products, applicability limits (notably kinematic viscosity <2.0 mm2/s at 100 °C for the primary table), and references the acceptable kinematic-viscosity measurement methods required as input.

Q: Who typically uses it?

A: Analytical and quality-control laboratories, lubricant manufacturers and formulators, test houses, OEM technical staff, and standards/specification writers who need a standard method for reporting and comparing the temperature dependence of viscosity.

Q: Is it current or superseded?

A: D2270-24 (published/issued in 2024) is the current active version of the practice. The ASTM store lists the D2270-24 version as active (ASTM records show last update in May 2024).

Q: Is it part of a series?

A: D2270 is part of the ASTM D02 suite of petroleum and lubricant standards (Book of Standards volume 05.01) and is commonly used together with viscosity measurement methods such as ASTM D445 and D7042, and with related guidance in ASTM D341.

Q: What are the key keywords?

A: Viscosity index, VI, kinematic viscosity, cSt, 40 °C, 100 °C, lubricating oil, D2270, viscosity-temperature dependence.