Overview
EN ISO 15785:2002 (ISO 15785:2002) defines rules for the symbolic presentation and indication of adhesive, fold and pressed joints in technical drawings. Adopted by CEN as EN ISO 15785, the standard establishes standardised drawing symbols, line conventions and annotation practices so that joints are unambiguously communicated on engineering and mechanical drawings.
Key topics and technical requirements
- Scope: Rules for representing adhesive joints, fold joints, and pressed joints in technical/engineering drawings.
- Graphical symbols: Standardised symbols for
- Adhesive surface joint and inclined adhesive joint
- Fold joint
- Pressed joint
Symbols follow the presentations given in the standard’s figures and Annex A.
- Line conventions:
- Joint symbols are drawn with a continuous wide line (see ISO 128-24).
- Leader lines and reference lines use a continuous narrow line (see ISO 128-22); leader lines terminate in an arrow.
- Distance between symbol and reference line is at least 2d (d defined below).
- Symbol sizing:
- Line width d = 0.1 × h, where h is the lettering height (per ISO 3098-0).
- Annotations and dimensions:
- Reference lines can include dimensions of the cross-section (width, height, punch diameter, depth), material designations and additional requirements (the latter may be placed in a forked reference line).
- Joint location dimensions must follow ISO 129-1 conventions.
- Special indications:
- Continuous adhesive around a part’s periphery is indicated by adding a circle at the leader/reference intersection.
- Adhesive joints limited to an area use a long-dashed double-dotted narrow line (type 05.1.8 per ISO 128-24).
- Compatibility: Symbols for some joints match those in ISO 2553 (welded/brazed/soldered joint symbols) where configuration is identical.
Applications and users
This standard is intended for:
- Mechanical and product design engineers
- CAD/drafting professionals and technical illustrators
- Manufacturing, assembly and quality-control teams
- Technical documentation specialists and standards coordinators
Practical benefits include consistent drawing interpretation, reduced manufacturing errors, clearer supplier drawings, and improved interchangeability across organisations and countries.
Related standards
- ISO 2553 - Welded, brazed and soldered joints (symbolic representation)
- ISO 128 series - General principles for drawing lines and leader/reference lines
- ISO 129-1 - Indication of dimensions and tolerances
- ISO 3098-0 - Lettering requirements
- ISO 17659 - Terms for welded joints (illustrative definitions)
Keywords: EN ISO 15785, ISO 15785:2002, technical drawings, symbolic presentation, adhesive joints, fold joints, pressed joints, drawing symbols, mechanical engineering documentation.
