ISO 5421:1977

Overview

ISO 5421:1977 specifies the dimensions and tolerances for ground high speed steel (HSS) tool bits used in metal cutting and machining operations. Developed by ISO Technical Committee ISO/TC 29 (Small Tools), this international standard provides uniform specifications for various shapes of HSS tool bits, including round, square, rectangular, and trapezoidal sections. The standard was first published in August 1977 and is intended to ensure consistency, interchangeability, and quality in the manufacture of high speed steel tool bits.

Key Topics

• Scope: Defines dimensions for ground high speed steel tool bits in multiple cross-section shapes.
• Tool Bit Types:
  • Round section tool bits
  • Square section tool bits - may include slanted ends by mutual agreement
  • Rectangular and trapezoidal section tool bits
• Dimensions and Tolerances: Precise millimeter measurements for length, width, thickness, and related parameters are detailed.
• Interchangeability: Emphasizes that tool bits manufactured according to this standard will be compatible with power-operated and manual tools.
• User-Supplier Agreements: Allows for customization such as slanted ends or one square end on parting-off blades, provided overall dimensions comply with the specified requirements.

Applications

ISO 5421:1977 is critically useful for manufacturers, suppliers, and users of HSS tool bits, especially in industries where cutting tools must meet strict high-speed machining requirements.

• Metalworking Industry: Standardized tool bits enable reliable tool performance in shaping, turning, parting-off, and other cutting processes.
• Power-Operated Tools: Ensures compatibility of tool bits with machine tool holders and chucks.
• Tool Manufacturing: Helps manufacturers produce tools that meet internationally recognized dimensional standards, simplifying export and supplier evaluation.
• Quality Assurance: Facilitates inspection and quality control by providing clear size and tolerance benchmarks.

Related Standards

Users interested in high speed steel tools and cutting equipment may also consider:

• ISO 4957 - Tool steels including high speed steel grades and properties.
• ISO 513 - Cutting tool nomenclature and terminology.
• ISO 8688 - Test conditions for metal cutting tools.
• ISO/TC 29 - Ongoing technical committee publications related to small tools and cutting bits.

Keywords: ISO 5421, high speed steel tool bits, HSS tool bits standard, ground tool bits, cutting tool specifications, tool bit dimensions, metal cutting tools, power-operated tool bits, international standard for tool bits, machining tool bits.