Article | REF: BM7020 V1

Functional rating

Author: François VILLARS

Publication date: April 10, 1999

You do not have access to this resource.
Click here to request your free trial access!

Already subscribed? Log in!


Overview

Français

Read this article from a comprehensive knowledge base, updated and supplemented with articles reviewed by scientific committees.

Read the article

AUTHOR

  • François VILLARS: Graduate engineer from École Centrale de Lyon - Head of gearbox calculations at PSA Peugeot-Citroën

 INTRODUCTION

Functional dimensioning is based on an in-depth and exhaustive study of the product's suitability for use, enabling us to define the dimensions of the functional elements and their relative positions, with a dimensioning that is neither insufficient nor excessive.

To work correctly, you must first carry out a functional study of the assembly under study, using appropriate methods (functional analysis...). This will help define the actual functions to be satisfied, and facilitate the creation of a list of "dimension chains" to be verified.

It should also be remembered that "functional dimensioning" is to be understood in the broadest sense, i.e. that, in addition to dimensions and tolerances, it encompasses all other specifications, provided they are functional in that they condition suitability for use (geometric tolerancing, material, mechanical and chemical characteristics, surface finish, etc.) and even those that condition saleability: reliability, appearance, safety (no sharp edges).

However, it's important not to be too purist, because if you want to remain functional, you run the risk of forgetting conditions that are implicit in the prescription method: temperature resistance, which may exclude certain plastics, corrosion resistance (steel, magnesium) or oil resistance (for clutches and gearbox synchronizers).

The aim of this article is to advance understanding of the notion of the functional in the dimensioning of technical drawings issued by design offices, especially detail drawings, known as definition drawings (of the finished product).

Note :

In this article, all dimensions are in millimeters, and it is customary in this field to indicate values without units, so as not to make the writing more cumbersome.

You do not have access to this resource.

Exclusive to subscribers. 97% yet to be discovered!

You do not have access to this resource.
Click here to request your free trial access!

Already subscribed? Log in!


The Ultimate Scientific and Technical Reference

A Comprehensive Knowledge Base, with over 1,200 authors and 100 scientific advisors
+ More than 10,000 articles and 1,000 how-to sheets, over 800 new or updated articles every year
From design to prototyping, right through to industrialization, the reference for securing the development of your industrial projects

This article is included in

Material processing - Assembly

This offer includes:

Knowledge Base

Updated and enriched with articles validated by our scientific committees

Services

A set of exclusive tools to complement the resources

Practical Path

Operational and didactic, to guarantee the acquisition of transversal skills

Doc & Quiz

Interactive articles with quizzes, for constructive reading

Subscribe now!

Ongoing reading
Functional rating