Overview
EN ISO 9222-1:1995 (ISO 9222-1:1989) - Technical drawings - Seals for dynamic application - Part 1: General simplified representation - is a drawing standard adopted by CEN for the simplified depiction of dynamic seals on mechanical engineering drawings. It defines a compact, unambiguous way to show seals when the exact shape or lip configuration is not required (for example in assembly drawings or general arrangement documentation). Use of this standardized symbol reduces drawing clutter, speeds drafting, and avoids misinterpretation.
Key Topics and Requirements
- When to use: Apply the general simplified representation when it is unnecessary to show the exact contour or lip details of a seal (assembly drawings, schematic layouts, catalog overviews).
- Symbol format: Represent the seal by a square with a freestanding diagonal cross centered inside the square. The diagonal cross must not touch the square outlines.
- Line work and scale:
- Use the same visible-outline line thickness as other visible outlines on the drawing (line type A per ISO 128).
- The seal symbol must be drawn to the same scale as the rest of the drawing.
- Sealing direction: If direction matters, indicate it by adding an arrowhead to the diagonal cross (or specify direction by text). If direction is unimportant the basic square + cross is sufficient.
- Exact contour option: If the true cross-sectional contour is required, show the true outline with a centered diagonal cross (cross not touching outlines).
- Hatching: Avoid hatching in simplified representations. If necessary (e.g., more detailed catalogue illustrations), hatch all inserts and similar elements with continuous thin lines (line type B per ISO 128) or use blackening for clarity.
- Consistency: To prevent misunderstandings, use only one kind of simplification (general or detailed) on a single drawing.
Practical Applications and Users
- Who uses it:
- Mechanical design engineers and CAD technicians
- Drafting offices producing assembly or installation drawings
- Technical illustrators and spare-parts catalog creators
- Seal and component manufacturers preparing standardized documentation
- Where it helps:
- Assembly drawings, installation manuals, procurement documents
- Product catalogs and parts lists where full seal geometry is unnecessary
- Cross-disciplinary drawings where clarity and speed of interpretation are priorities
Related Standards
- ISO 9222-2 - Detailed simplified representation (for when lip configuration and more detail are required)
- ISO 128 - Technical drawings - General principles of presentation (line types, hatching)
- Reference: EN ISO 9222-1:1995 corresponds to ISO 9222-1:1989
Keywords: EN ISO 9222-1:1995, ISO 9222-1, technical drawings, seals for dynamic application, simplified representation, assembly drawings, mechanical engineering drawings, seal representation.