Welded joints in pipes play a vital part in industry. They are used in oil refineries (see Fig. 1-6), chemical plants, power generating stations, and food processing plants. Welded joints in pipes also play a vital role in the transportation of liquids and gases, as exemplified

by cross-country pipelines. In the construction industry pipe welded members are used to support heavy loads.

Since public health and safety are involved in almost all of these cases, codes and standards have been established to protect the public interest. The following organizations are primarily responsi­ble for these codes:

American National Standards Institute (ANSI)

The American Welding Society, Inc. (AWS)

American Society of Mechanical Engineers (ASME)

American Petroleum Institute (API)

It is not possible to list here all of the standards and codes that apply to the design and construction of pipe welded joints. The welder should, however, be aware of those affecting the job on which he is working.