Common Drawing standards in Europe/Asia

[mdemers]

Hi all,

I work for a R&D company in Canada, and we're considering the opportunity to sub-contract the manufacturing of mechanical components to machine shops in Europe and/or Asia. In North America, our drawings comply (entirely or in part) to ASME Y14.100-2000 and MIL-DTL-31000B, both for metric and inch drawings but we'd, of course, like overseas companies to understand the drawings we send them.
I'd like to hear from you, a few people from Europe and Asia (no more than a dozen people, please), about the drawing standards that you use.
Thank you very much.

Mat

 

[dr_gallup]

I've worked in Europe. Most companies use a mix of ISO and national standards. The Germans use DIN. I believe most Japanese use JIS. As long as your drawings clearly state what standards they adhere to it should not be a problem. You have to be careful with ISO standards because they are written as lots of separate little standards, not big all encompassing standards. Some of them are mutually exclusive. It is necessary to get very specific about which ISO standards you use.

Lots of American companies (and non-American) do not specify drawing standards in their title block which can lead to major problems. When I worked in France they did not specify any standards on their drawings. I asked how they could interpret their drawings and was told "We all go to the same schools and they all teach us the same way". So I gave them a little (tricky) test and got a different answer every time!

In particular, beware ISO 8015:1985 Fundamental tolerancing principal. It directly contravenes the ANSI/ASME Y14.5M envelope requirement. You can get around this evil spec by invoking national standards.

Also beware of ISO 4288:1996 Rules and procedures for the assessment of surface texture. This is the biggest piece of horse hockey ever written. It includes the "16% rule" which states that a surface is considered acceptable if not more than 16% of the measured values exceed the specification. I think not! Under ANSI you would reject for a single measurement outside the specification.

So in summary, it is OK to use national standards for international business but be very carful to specify which standards you use.