ISO 25178 defines 3D surface texture parameters and the associated specification operators. It also describes the applicable measurement technologies, calibration methods, together with the physical calibration standards and calibration software that are required. A major new feature incorporated into the standard is coverage of non-contact measurement methods, already commonly used by industry, but up until now lacking a standard to support quality audits within the framework of ISO 9000. For the first time, the standard brings 3D surface metrology methods into the official domain, following 2D profilometric methods that have been subject to standards for over 30 years. The same thing applies
Symbols and conventions used in welding documentation Symbols and conventions used in welding documentation The symbols and conventions used in welding documentation are specified in national and international standards such as ISO 2553 "Welded, brazed and soldered joints -- Symbolic representation on drawings" and ISO 4063 "Welding and allied processes -- Nomenclature of processes and reference numbers". The US standard symbols are outlined by the American National Standards Institute and the American Welding Society and are noted as "ANSI/AWS". Due in part to the growth of the oil industry, this symbol set was used during the 1990s in about 50% of the world's welding operations. An ISO