ABSTRACT
The publication of an ISO standard is usually the result of a process in which experts from different countries participate in developing a document that properly describes a product. For fasteners this takes place in two technical committees (TC 1 and TC 2), dealing with screw threads and fasteners, respectively. The very fact that ISO currently has over 170 very specialized TCs gives us some idea of how important the issue of fastener standardization was when ISO was formed in 1946. It is certainly no less important today. If all the countries signing off on the ISO standards used them as they are written, we would have total harmonization in this area worldwide. The problem is that some countries, including the United States, prefer to do some reworking before publishing a national standard based on the ISO agreement. Since "functional" conformance, as it is usually stated, does not necessarily mean that the part "specs" out exactly dimensionally, we may get rejects due to different tolerancing, etc., even if the part is, in fact, functionally interchangeable with another standard.
