ISO 129-1-2018 pdf free.Technical product documentation (TPD) – Presentation of dimensions and tolerances – Part 1: General principles.
This document establishes the general principles for presentation of dimensions and associated tolerances that apply to 2D technical drawings in all disciplines and trades hut which can also he applied to 3D applications.
This document does not cover the application of dimensional tolerances and their meaning. See ISO 14405-1 for tolerancing principles. This document can only be used to describe the nominal model of a drawing, not the non-ideal surface model (skin model) used for tolerancing purposes (for more information on tolerancing specifications, see the list of GPS standards listed as normative reference or as bibliography)
Considering the ISO 14405 series, the presentation of tolerance indication is unambiguous when it is applied to a dimension which is a size and ambiguous when the dimension is not a size.
All rules presented in this document are available for any type of drawing (see ISO 29845).
In addition, this document introduces the concept of property indicators, developed length, between. surface indicators, flag notes and textual instructions.
NOTE I All figures are shown in 2D views only.
NOTE 2 Additional information and details for construction engineering are given in ISO 6284.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 128-20, Technical drawings — General principles of presentation — Part 20: Basic conventions for lines ISO 128-2 2, Technical drawings — General principles of presentation — Part 22: Basic conventions and applications for leader lines and reference lines
ISO 128-24:2014, Technical dra wings — General principles of presentation — Part 24: Lines on mechanical engineering drawings
ISO 3098 (all parts). Technical product documentation — Lettering
ISO 10209, Technical product documentation — Vocabulary — Terms relating to technical drawings, product definition and related documentation
ISO 14405 (all parts), Geometrical product specifications (GPS) — Dimensional tolerancing
ISO 81714-1, Design of graphical symbols for use in the technical documentation of products — Part 1: Basic rules
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10209 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.orgJhp
— I EC Electropedia: available at http://www.electropedia.org/
3.1 Elements of dimensioning
3.1.1 centre line
line or set of two perpendicular lines used to represent a median feature. e.g. an axis or a centre plane
3.1.2 dimension line
straight or curved line with terminators at each end or origin and terminator at each end, indicating the size of a feature or the extent of a feature or between two features, or between a feature and an extension line (3L3), or between two extension lines
3.1.3 extension line
line which is an extension of a feature outline or of a centre line (ILl)
3.1.4 origin symbol
circle indicating the start of running dimensioning or coordinate dimensioning
3.2 DimensIons
3.2.1 angular dimension
angle of an angular feature of size or angle between two features
4 Presentation of dimensions
4.1 Presentation rules
4.1.1 Dimensions
Only the dimensions necessary to unambiguously define the nominal geometry (nominal model) shall be presented. Each dimension shall be presented only once by using a dimension line, a dimension value preceded, and if necessary, by a property indicator. When there is a need to repeat the presentation of a dimension, auxiliary dimensions may be used.
Dimensional values indicated in decimal notation, shall use a comma as the decimal marker.
Unless otherwise specified, dimensions shall be indicated for the finished state of the dimensioned feature.
The text of all dimensions, graphical symbols and annotations shall be indicated above the dimension line and read from the bottom. When the text of a dimension, symbol or annotation is presented vertically, it shall read from the right. The determination of orientation is based on the centre of the dimension, symbol or annotation.
1)imensions alone are not sufficient to define the requirements of a product. Dimensions shall be used with other specification techniques as applicable, e.g. general tolerances, geometrical tolerancing or surface texture requirements.
4.1.2 Repeated dimensions
When a feature is repeated on the drawing, it is possible to simplify the indication of its dimension on the drawing by indicating:
— on one instance of the feature, the nominal dimension (with a property indicator symbol if appropriate), preceded by the associated number of repetition, followed by a multiplication symbol (x) and a space (e.g. 2x e18) (see FigurelQ). To avoid confusion, it is possible to identify each member of the repetition using a reference identifier (e.g. letter or symbol) (see Eigure64);
— a nominal dimension (with a property indicator symbol if appropriate) above a reference line, which is attached to each member of the repetition (see Figures 49 and 5).
4.1.3 Out of scale dimensions
By default, a dimension line is drawn to the scale of the drawing. In exceptional cases, in 2D drawing only, when the dimension value does not correspond to its dimension scale value (out-of-scale features), the dimension value shall be marked by underlining the dimensional value (see Z.1I. and Figure 70).
4.1.4 Auxiliary dimensions
A dimension value can be defined as a dimension for information purposes only. In this case, the dimension value shall be placed into parenthesis, ( ). This kind of dimension is called an auxiliary dimension (see Z1Z and Figures 65 and 612).
4.1.5 Theoretically exact dimensions
When a dimension value shall be considered as a theoretical exact dimension and not associated with general ± tolerancing or not an auxiliary dimension, it shall be placed in a rectangular frame (in accordance with Iso 1101, LU and Figure 71).ISO 129-1 pdf free download.