ISO 6746-2:2003

Overview

ISO 6746-2:2003 - "Earth‑moving machinery - Definitions of dimensions and codes - Part 2: Equipment and attachments" specifies a standardized reference system and a coding method for defining and identifying equipment and attachment dimensions used in terminology standards and commercial specifications for earth‑moving machinery. It applies to equipment and attachments for the basic types of earth‑moving machinery defined in ISO 6165.

Key topics

• Three‑dimensional reference system
  • Uses zero planes (Y plane through the machine longitudinal centreline, X plane vertical perpendicular to Y, Z plane horizontal) to determine coordinates.
  • Defines positive coordinate directions: forward from X zero, right from Y zero, and above Z zero.
• Ground reference plane (GRP)
  • Specifies the plane on which a machine is placed for measurements; for base machines this is normally a hard, level surface; for attachments it may be hard surface or compacted earth. The intended surface must be defined in specific terminology or commercial standards.
• Coding system for dimensions
  • Each dimension is assigned a code composed of two capital letters plus a reference number.
  • Standard letter pairs: HH = height, WW = width, LL = length, RR = radius/reach, AA = angle.
  • Additional reference numbers can be appended as needed for specific equipment or attachments.
• Illustrative examples (normative annexes)
  • Annexes A–E provide example dimension definitions and codes (e.g., HH xx blade height: Z‑distance between GRP and top of blade in specified conditions), demonstrating practical implementation.

Applications

• Standards development: Used by ISO technical committees and national standards bodies to create consistent terminology and dimension definitions for earth‑moving equipment.
• Manufacturers and OEMs: Standardizes dimension reporting for attachments, helping ensure clear product specifications and interoperability.
• Procurement and commercial specifications: Enables unambiguous dimension codes in tender documents, purchase orders and technical data sheets.
• Design, documentation and maintenance: Provides a common reference for engineering drawings, user manuals and service documentation where equipment and attachment dimensions must be described precisely.

Related standards

• ISO 6165 - Basic types and vocabulary of earth‑moving machinery (normative reference used by ISO 6746-2).
• ISO 6746‑1 - Definitions and codes for base machine dimensions (complements Part 2).

Keywords: ISO 6746-2, earth-moving machinery, equipment and attachments, dimensions, coding system, three-dimensional reference system, ground reference plane, ISO 6165, nomenclature, commercial specifications.