scope:

This standard 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 refinery services. This standard is primarily intended for gears that are in continuous service without installed spare equipment. Gear sets furnished to this standard shall be considered matched sets.

NOTE: The purchase of a spare set of gear rotors or a complete gear unit does not mean that the quiipment is spared.

This standard includes related lubricating systems, controls, instrumentation, and other auxiliary equipment. This standard is not intended to apply to gears in general-purpose service, which are covered by API Standard 677; to gears integral with other equipment; or to gears other than helical.

Note: A bullet (•) at the beginning of a paragraph ndicates that either a decision is reqired or further information isto be provided by the purchaser. The information should be indicated on the data sheets (see Appendix A); otherwise it should be stated in the quotation request or in the order.

The following gear-driven applications may be covered by this standard:

a. Speed increasers, including those for centrifugal compressors, axial compressors, blowers, rotary positive displacement compressors, contactors, separators, and centrifugal pumps.

b. Speed reducers, including those for reciprocating compressors, rotary positive displacement compressors, contactors, centrifugal pumps, extruders, generators, and fans.