The fourth edition of API Std 677 die gear and Planetary Gear Units for General use in the Petroleum, Chemical and Natural Gas industries has been published in September 2021.

The fourth edition of API Std 677 die gear and Planetary Gear Units for General use in the Petroleum, Chemical and Natural Gas industries has been published in September 2021.  The standard covers minimum requirements for enclosed single and multistage gear installations with parallel axis spur and helical gears for general use in the petroleum, chemical, and natural gas industries.  General purpose die head gears manufactured according to this standard shall have pitch line speeds not exceeding 60 m/s (12,000 ft/min).