This standard specifies the type, size, basic parameters, technical requirements, test methods, inspection rules, signs, labels, and packaging of reducers for scraper conveyors (hereinafter referred to as reducers). This standard applies to parallel arrangement conical and cylindrical gear reducers and planetary gear reducers and vertical arrangement planetary gear reducers. The reducer is suitable for scraper conveyors and trough scraper conveyors used in coal mine underground working surfaces, and is also suitable for belt conveyors.