ASTM D2422-24 PDF

Full title and description

Standard Classification of Industrial Fluid Lubricants by Viscosity System — a short classification standard that establishes a uniform series of viscosity grades (ISO VG) and a reference temperature for designating, specifying, and selecting industrial fluid lubricants.

Abstract

This classification applies to petroleum-base fluid lubricants and blendable nonpetroleum materials used as industrial fluids (bearings, gears, compressors, hydraulic fluids, etc.). It defines viscosity grades (ISO VG 2 through ISO VG 3200), a reference temperature of 40 °C, and the kinematic viscosity range covered (2 cSt to 3200 cSt). The classification does not evaluate lubricant quality and excludes automotive SAE-numbered oils.

General information

• Status: Active.
• Publication date: 2024 (designation D2422-24); document record last updated May 24, 2024.
• Publisher: ASTM International (ASTM).
• ICS / categories: 75.100 (Lubricants, industrial oils and related products).
• Edition / version: D2422-24 (current active revision).
• Number of pages: 2.

Scope

The classification covers industrial fluid lubricants with kinematic viscosities from 2 cSt to 3200 cSt measured at the reference temperature of 40 °C, and defines the standard ISO VG grades used to group these fluids (ISO VG 2, 3, 5, 7, 10, 15, 22, 32, 46, 68, 100, 150, 220, 320, 460, 680, 1000, 1500, 2200, 3200). It applies to petroleum-base fluids and compatible nonpetroleum blends used for bearings, gears, compressor cylinders, hydraulic systems, and similar industrial applications.

Key topics and requirements

• Definition of a uniform set of ISO VG viscosity grades for industrial lubricants (VG 2 → VG 3200).
• Reference temperature for classification: 40 °C (viscosity measured as kinematic viscosity in cSt/mm²/s).
• Covers kinematic viscosity range 2–3200 cSt and establishes viscosity tolerances for each grade.
• Specifies nomenclature and intent to reduce intermediate/unnecessary viscosity grades (no assessment of other lubricant properties).
• Exclusion: not intended for automotive oils identified by SAE numbers (different classification systems).

Typical use and users

Used by lubricant manufacturers and suppliers for product designation, by equipment designers and maintenance engineers for specifying lubricant viscosity for components (bearings, gearboxes, hydraulics, compressors), and by procurement/specification writers and testing laboratories to ensure consistent viscosity grading and communication across supply chains.

Related standards

Closely related to ISO 3448 (industrial liquid lubricants — ISO viscosity classification) which defines the VG grade midpoints and limits, and to ASTM test methods such as ASTM D445 (kinematic viscosity measurement). For automotive engine-oil classification (different domain) see SAE J300. The D2422-24 revision supersedes earlier editions of the same designation (historical: D2422-97 and subsequent reapprovals/revisions).

Keywords

viscosity classification, ISO VG, industrial lubricants, kinematic viscosity, hydraulic fluids, bearings, gear oils, lubricant grades, ASTM D2422, 40 °C reference

FAQ

Q: What is this standard?

A: ASTM D2422-24 is a short classification standard that defines a uniform set of viscosity grades (ISO VG) and a nomenclature system for industrial fluid lubricants measured at 40 °C.

Q: What does it cover?

A: It covers kinematic viscosity classification for petroleum-base and blendable nonpetroleum industrial fluids ranging from about 2 cSt to 3200 cSt at 40 °C, and lists the ISO VG grades used for designation. It does not assess lubricant performance or other properties.

Q: Who typically uses it?

A: Lubricant manufacturers and formulators, equipment designers and maintenance engineers, specification writers, procurement professionals, and testing laboratories use the standard to ensure consistent viscosity designation and selection.

Q: Is it current or superseded?

A: D2422-24 is the current active edition (designation D2422-24); it replaces earlier D2422 editions/reapprovals and was recorded as active/updated in 2024.

Q: Is it part of a series?

A: D2422 is part of ASTM's petroleum products and lubricants series (Book of Standards volume covering petroleum products, liquid fuels, and lubricants) and aligns with the international ISO viscosity-classification system (ISO 3448); it is also used alongside viscosity test methods such as ASTM D445.

Q: What are the key keywords?

A: ISO VG, viscosity grade, kinematic viscosity, 40 °C, industrial lubricant, hydraulic fluid, gear oil, ASTM D2422.