This standard specifies the type and basic parameters, technical requirements, test methods and inspection rules, marking, packaging, and transportation of planar enveloping toroidal worm reducers (including planar double-enveloping toroidal worm reducers, hereinafter referred to as reducers). and storage. This standard applies to reducers in metallurgy, mining, lifting, transportation, construction, petroleum, chemical industry, aerospace, navigation equipment or precision transmission.