ISO 21948:2001

Overview

ISO 21948:2001 is an international standard developed by the International Organization for Standardization (ISO) that specifies the nominal dimensions, tolerances, and designations for coated abrasive plain sheets. These sheets are intended primarily for use with hand-held grinding machines or for manual sanding applications. The standard ensures consistency and quality across manufacturers and users, facilitating compatibility and reliable performance in abrasive tasks.

This standard is managed by ISO Technical Committee ISO/TC 29, Small Tools, Subcommittee SC 5, focusing on grinding wheels and abrasives.

Key Topics

• Dimensions and Tolerances
  ISO 21948 defines the nominal sizes for plain coated abrasive sheets along with allowed dimensional deviations. Standard sizes include combinations such as 70 x 115 mm, 230 x 280 mm, and others, ensuring uniformity for end-users and manufacturers.

• Test Conditions
  Dimension tolerances are validated under specific environmental conditions following ISO 554 standards, including:

  • Temperature: 20 °C ± 2 °C
  • Relative Humidity: 65% ± 5%
    Sheets must be conditioned for at least 24 hours at these settings before measurement to guarantee accuracy.

• Designation Format
  The standard outlines a uniform way to designate plain sheets:

  • The term “Plain sheet”
  • Reference to ISO 21948
  • Dimensions (Thickness x Length)
    For example: Plain sheet ISO 21948 - 230 x 280

• Marking Requirements
  Each sheet must be clearly marked with:

  • The grain size of the abrasive material
  • Manufacturer, supplier, or importer’s name or trademark
    This marking facilitates traceability and quality assurance.

Applications

ISO 21948:2001 is critical in ensuring high-quality performance and interchangeability in various abrasive tasks such as:

• Hand Sanding: Providing consistent abrasion surfaces for manual finishing and smoothing of wood, metal, and plastic surfaces.
• Hand-Held Grinding: Used with portable grinders in manufacturing, automotive repair, metal fabrication, and maintenance industries.
• Surface Preparation: Ensuring adequate control over abrasive dimensions helps in preparing surfaces for painting, coating, or bonding.
• Quality Assurance: Manufacturers use this standard to maintain uniform sheet sizes for packaging, inventory, and customer specifications compliance.

By adhering to ISO 21948, industries can reduce variability in abrasive products, improve worker safety, and enhance overall productivity.

Related Standards

For comprehensive guidance on coated abrasives, the following related ISO standards offer complementary specifications:

• ISO 6344 Series:

  • Part 1: Grain size distribution test methods
  • Part 2: Determination of grain sizes for macrogrits (P12 to P220)
  • Part 3: Determination of grain sizes for microgrits (P240 to P2500)

• ISO 554:1976: Standard atmospheres for conditioning and testing of products, which sets the environmental criteria essential for testing abrasive sheets.

These standards collectively assist manufacturers and users in achieving consistent abrasive grain sizes, conditioning, and performance characteristics.

ISO 21948:2001 stands as a key reference for anyone involved in the production, quality control, or application of coated abrasive plain sheets, helping maintain global standards and simplifying procurement decisions in abrasive materials.