Please note that any addenda or errata may not be included in translated editions of this standard.Includes December 2006 errata.

API Std 613 covers the minimum requirements for special-purpose, enclosed, precision single- and double-helical one- and two-stage speed increasers and reducers of parallel-shaft design for petroleum, chemical and gas industry services. This standard is primarily intended for gear units that are in continuous service without installed spare equipment.

This standard includes related lubricating systems, controls, instrumentation, and other auxiliary equipment. API Std 613 is not intended to apply to gear units in general-purpose service, which are covered by API Std 677, to gears integral with other equipment, such as integrally geared compressors covered by Std 617 or Std 672, or to gears other than helical.