ASME International

Inverted Tooth (Silent) Chains and Sprockets
 N B29.2M

Annotation

FOREWORD

Preparatory work during the late 1930s and early 1940s by the Silent Chain Division of the Association of Roller and Silent Chain Manufacturers (ARSCM, now the American Chain Association) resulted in agreement on standardization of silent chain primarily on the basis of standardized sprocket tooth design. Since individual chain manufacturers employed various chain joint designs, itwas agreed that standards on chain detail would be limited to ensure interchangeability of chains on sprockets of any number of teeth. At a meeting of representatives of all major American silent chain manufacturers in September 1944, under the auspices of the ARSCM, recommended "Engineering Standards for Industrial Silent Chain and Sprockets" were agreed upon. Formulas for sprocket designwere expanded into tables, whichwere approved and adopted by the ARSCM in April 1945. Supplementary information on sprocket tooth cutters was added, and all of the datawere incorporated in a comprehensive report, Industrial Standards for Industrial Silent Chains, Sprockets, and Cutters. This report, with further refinements by minor revisions in 1949 and 1950, was then submitted to the Sectional Committee for review and approval as an American Standard.

The Sectional Committee accepted the recommendations with some minor revisions in 1950 and referred it to ASME and The Society of Automotive Engineers (SAE) for their approval as sponsors of the Committee, with subsequent transmission to the American Standards Association (ASA) for final acceptance as an American Standard. After approval by ASME and SAE, it was accepted by ASA on November 9, 1950 as American Standard B29.2.

In 1956, the Sectional Committee authorized a revision to the standard to bring it up to date. The revised standard was approved by the American Standards Association on July 11, 1957. This revision was in use for many years and was reaffirmed by ANSI on January 4, 1971. (ASA became ANSI in 1969.)