Fachzeichnungen

Fachzeichnungen, or technical drawings, are precise graphical representations of objects used in engineering and manufacturing. They convey form, size, geometry, materials, finishes and production methods so that parts can be manufactured and assembled correctly.

Historically produced by hand on drawing boards, Fachzeichnungen are now primarily created with computer-aided design (CAD) tools. They span multiple disciplines, including mechanical, electrical, civil engineering and architecture, and encompass part drawings, assembly drawings, installation drawings and schematic diagrams.

Drawings follow standardized conventions to ensure clear communication. They employ orthographic or other projection methods, with regional differences such as first-angle projection common in German-speaking countries and third-angle projection prevalent in many English-speaking regions. Key elements include dimensioning, tolerances, material specifications, surface finishes and notes, as well as a title block that identifies the drawing, parts list and revision history.

A typical Fachzeichnung may include scales, reference designations, a bill of materials, welding or fastener symbols, and, where appropriate, geometric dimensioning and tolerancing (GD&T). Exploded views help illustrate assembly sequences, while sectional views reveal hidden details that are not visible in exterior views.

Standards and interoperability are central to Fachzeichnungen. They adhere to national and international guidelines, such as ISO standards and, in many countries, corresponding national equivalents (for example, DIN standards in Germany). Modern practice often integrates drawings with digital product data, linking geometry to manufacturing instructions, quality controls and maintenance information.