Machining process standards explained: ISO, GB, ASME, how to ensure global manufacturing consistency?

Machining process standardsIt's the universal language of quality. This article explains how ISO, GB, ASME and other core standard systems regulate dimensional tolerances, shape and position tolerances, and surface finishes to ensure global interchangeability and reliability of parts.

Machining process standards: the cornerstone and universal language of globalised manufacturing

Introduction: From the scenario of “one part produced in multiple locations around the world”, the importance of standards is introduced - without standards, there is no modern large-scale, collaborative manufacturing.

I. Why are standards of workmanship so important?

(interchangeability, quality consistency, communication efficiency, trade facilitation)

II. Introduction to the core machining process standards system

1. International standards: ISO systems (e.g. ISO 2768 general tolerances)

2. Chinese national standard: GB system (correspondence with ISO)

3. American Standard: ASME Y14.5, etc.

4. Industry and internal standards

III. Core content areas covered by the standards

1. System of dimensional tolerances and fits (base-hole system/base-shaft system)

2. Geometrical tolerances (form and position tolerances) symbols and meanings quick check

3. Surface roughness symbols and evaluation parameters (Ra, Rz)

4. Norms for the labelling of drawings

Fourth, a chart to see how the standard in the processing of landing

(Flowchart: customer drawing labelling standard → engineer interpreting standard → programming and process setting → operator executing → QC inspecting according to standard)

Conclusion & CTA: Standards are frameworks that need to be translated into detailed machining process requirements specific to each order. Read our next article on how to develop specific requirements (link to article four).

FAQ.

“What if the tolerance is not marked on the drawing?” (A: Usually follow ISO 2768-mK or similar general tolerance standards.)

“American Standard and National Standard drawings, what is the biggest difference between reading the drawings?” (Answer: the perspective projection method is different: the American Standard commonly used third corner projection, the national standard with the first corner projection, you need to first confirm when looking at the drawings.)