AS291B SURFACE ROUGHNESS (AA)

This standard provides a method of applying surface roughness, waviness and lay control. The data included herein also covers the method of applying surface roughness symbols and related designations to drawings and specifications of parts when applicable. This standard is based on the Arithmetical Average (AA) method of instrumentation. Data compiled are based on current manufacturing practices. It also includes a summary of data published in the American Standards Association publication ASA B46.1 - 1955 which may be referred to for supplementary data.