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 [or 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 128-22, Technical drawings — General principles of presentation — Part 22: Basic conventions and applications for leader lines and reference lines
ISO 128-24:20 14, Technical drawings — 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 terminologica) databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:/www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
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.
Dimensions 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 Figure 10). To avoid confusion, it is possible to identify each member of the repetition using a reference identifier (e.g. letter or symbol) (see Figure 64)
— 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 50).
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 2.1.1 and Figure 70).ISO 129-1 pdf free download.