Engineering drawing

A technical drawing is a document in graphic and written form with all necessary information for the production and for the description of the required functions and characteristics of a single- part, assembly, or an entire product displays and serves as part of the technical product documentation.

DIN 199 defines this as follows: " A technical drawing is a drawing in the type and completeness required for technical purposes, such as adherence to the display rules and dimensions registrations. " This definition takes into account the complex process statement, to create complete, standard-compliant Technical drawings is required and technical drawing is called.

Types of drawings

The subsequent use of the technical drawing defines the type of representation. Thus, it is of considerable importance whether the drawing is created for the manufacturing or assembly process or a spare parts catalog; they must satisfy each with different requirements.

For the manufacturing process, it is important that the representation as detailed as possible showing the part in question in a single drawing. This can be run as a full view or sectional drawing.

Group, or assembly drawings are used to illustrate the interaction of the various components for assembly, operating instructions and the presentation of spare parts. This also exploded drawings are suitable to represent perspective and broken down into its component parts of a complex object.

Depending on the industry, special rules apply for subscriptions. So defined as DIN 919 standards specific technical drawings in woodworking and metalworking

• Technical Drawings

Single-part drawing

3D exploded view

Interpretation of drawings

The presentation of items is done in one of the size or complexity of the product adapted scale. In order to view the entire product geometry, multiple views from different directions, detailed views are often necessary ( larger scale ), and section views. In order to characterize different materials, parts or cut surfaces, hatches are used.

Scale

Technical drawings are allowed only at certain scales, in accordance with ISO 5455. These are:

• Natural Scale: 1:1
• Reduction scales: 1:2; 1:5; 1:10 ... and multiples thereof
• Enlargement ratios: 2:1; 5:1; 10:1 ... and multiples thereof

Other scales are no longer permitted since 1979, but are still used occasionally.

Different standards are sometimes used in surveying for historical reasons, when old maps are re-measured. In the building industry, other standards apply to standards.

Mark sheet format, and title block

In Europe, the use of drawing formats up to DIN A0 DIN A4, for very small drawings in individual cases, A5, common. The sheet sizes obtained in each case by halving the next larger format. The folding of large format drawings for filing in ring binders according to DIN standard DIN 821 is standardized in DIN 824.

EN ISO 5457 defines the character sheet sizes for technical drawings. This standard replaces DIN 6771-6, since August 1999, previously DIN 823 replaced. The title block (according to EN ISO 7200, replaced the 2004 withdrawn DIN 6771-1 ) next to the product designation also drawing number, material specifications, scale, creation and approval information, information on the history or the revision level and other necessary information is entered.

In America and Asia are mostly other paper formats in use.

BOM

Above the title block in the lower right corner of the title block can be supplemented by a bill. If the space above the text field for example, in larger assemblies or assembly drawings are not sufficient, a separate BOM is usually created. The bill is one of the components used in the assembly of ( designation and number ).

Artboard

The canvas is divided into the drawing area on which the actual representation is shown, with the title block in the lower right corner. The drawing area is bounded by the edge of the drawing, not drawn out of the or may not be labeled. Outside of the drawing edge is a grid division with letters (vertical) and numbers (horizontal). Within the drawing area, the components with dimensions and tolerances are provided. These describe the dimensions of the component. The measuring of dimensions from the drawing by drawing the reader is not allowed. It is permissible to insert additional text to the description of the component within the drawing area.

Rules and standards

When creating technical drawings of a variety of rules and standards must be observed, the Technical Drawing are explained in detail in the article.

General tolerances

The information contained in the drawing are in particular the geometric shape and dimensions. Depending on the application, additional information is added. By general untoleranced and to certain extent (nominal dimensions ) tolerances related the complete interchangeability of the product shown is guaranteed. The quality of the surface of the subscribed component part is quantified by the roughness Ra. Mass production would not be possible without this Dimensioning methods.

Creating, copying, archiving and dissemination

Previously Technical drawings were done directly on the paper, reproduced by pauses and carefully kept the originals. Over time, various duplicating processes for technical drawings have developed, some of which are still used today.

The use of CAD software and thus possible copies of the CAD data displaces now partly the paper form of technical drawing, but usually also the drawings created with CAD be printed, plotted, or simply duplicated the required number of copies with a photocopier.

Today's technology allows completely to the disclosure of a technical drawing on paper to renounce, because increasingly the production areas with computers and monitors are equipped and dimensions and tolerance specifications can be made directly on the virtual three-dimensional model. The production planning and quality control can thus receive specially tailored to the specific needs pictures with ISO views and print them out only when actually needed (leave ).

For the version management and the provision of technical drawings in digital form increasingly document management and electronic archiving systems are used. In these, the necessary data are stored including as DWG, DXF, IFC.

Paper drawings and microfilms are still often used for archiving, since (such as mining ) required digital archiving unchanged over several centuries can not be guaranteed. For short-term archiving format PDF/A1 is recommended. Other formats, such as pixel-based data formats are common. In the past, HPGL was widespread.