WHY ISO STANDARDS SHOULD BE PREFERRED FOR METRIC FASTENERS?

The adoption of ISO Fastener Standards has ended 40 years of fasteners industry confusion. ISO standards are good engineering practice, they simplify inventory, and they enhance assembly uniformity. The United States started moving towards the use of metric fasteners in a significant way the early 1970s when ( FORD, GM, and CHRYSLER ) made a commitment to use the metric system for all new vehicle designs. Since the automotive industry uses more threaded fasteners than any other industry, the major fastener suppliers in the US started getting involved in the production of metric fasteners. The auto industry’s commitment to metric design was adopted so that one car design could be produced all over the world with the same metric standards.

 Before the adoption of the ISO standards, relatively low volumes of metric fasteners were used in the US. They were mostly used in maintenance applications for imported manufacturing equipment from Europe, with the majority coming from Germany. The German metric standards system is referred to as the DIN system and most of the fasteners imported from Europe were made to the DIN fastener standards.

The decision to adopt the metric system impacted all industrialized countries in the world. The car manufacturers wanted to be able to source products anywhere in the world and have the components be compatible regardless of where the parts were made, purchased, or assembled. This decision drove the need for the creation and use of common world standards for all components including fasteners.

THE ISO FASTENER COMMITTEE WAS FORMED TO STANDARDIZE METRIC FASTENER SYSTEMS:

Before the ISO standardization, several European and Asian countries had their own designs of metric fasteners as defined by their country standards. To standardize these designs the ISO TC2 Fastener Committee was formed. The predominant metric fastener standard at the time was the DIN standards.  So, it became the foundational metric fastener standard system from which the eventual ISO fastener standards evolved.

 In the meantime, more and more countries joined the ISO fastener standards efforts, and a true worldwide fasteners standards system was created. The growing adoption of ISO fasteners standards has resulted in the most industrialized countries withdrawing their country-specific standards and formally adopting the ISO standards as their metric fastener system.

GERMANY WITHDRAWS DIN STANDARDS IN 2001 TO ADOPT ISO FASTENERS STANDARDS:

The biggest endorsement of the ISO fastener standards was Germany’s official withdrawal of their DIN fasteners standards in 2001. International trade is increasing. US exports are critical to the US in reducing unemployment. US firms are adopting the ISO fasteners standards to assure what is produced in the US is acceptable to purchasers outside the US.  It is understood that many end users are still referring to DIN fastener standards because they are unaware of DIN withdrawing their standards in preference for the ISO standards. There is no law or rule that states that users cannot continue to use a withdrawn standard if they wish to do so. They should, however, realize that only the ISO standards will be maintained and updated.