What are the differences and connections between ASTM, ANSI, ASME and API?

ASTM：American Society for Testing and Materials,ASTM

ANSI：AMERICAN NATIONAL STANDARDS INSTITUTE: ANSI

ASME：American Society of Mechanical Engineers

API：American Petroleum Institute

ASTM develops and disseminates knowledge about standards for the characteristics and performance of materials, products, systems and services. ASTM standards are developed by the technical committee and drafted by the Standards Working group. ASTM standards are standards developed by unofficial academic groups. Currently, ASTM standards are divided into 15 categories.

ANSI is a non-profit standardization organization of the American National Standards Institute, but it has actually become a national standardization center, and all standardization activities are centered around it. Through it, the government-related system and the private system cooperate with each other, and play a bridge role between the federal government and the private standardization system. It coordinates and directs national standardization activities, assists standard-setting, research and use units, and provides domestic and foreign standardization information. It also functions as an administrative organ.

These four standards complement and learn from each other. For example, the standards used by ASME in materials are from ASTM, the standards in valves are more borrowed from API, and the standards in pipe fittings are from ANSI. The difference is that the focus of the industry is different, so the standards adopted are different. API,ASTM, and ASME are all members of ANSI.

The vast majority of the standards of the American National Standards Institute come from various professional standards. On the other hand, professional societies and associations can also formulate certain product standards based on existing national standards. Of course, it is not necessary to formulate its own association standards according to national standards.

ASME does not do specific work, the test and development work is almost completed by ANSI and ASTM, ASME only recognizes the specifications for their own use, so often see repeated standard numbers, the actual content is the same.