The document provides information about ZLYJ series gear reducers designed for plastic and rubber extrusion machines. It discusses the applicable scope, models, selection process, installation, usage, maintenance, and potential faults of the reducers. The key points are: 1. The reducers use alloy steel gears and shafts with precision of Level 6. They are suitable for input speeds below 1500 rpm and peripheral speeds below 20 m/s. 2. Selection involves choosing the proper ratio, model, assembly type based on mechanical power, axial thrust, and temperature requirements. 3. Installation and usage guidelines include filling oil levels and changing oil regularly. Potential faults include increased noise or temperatures, which require stopping use