The term "factory belts" can refer to a variety of synonyms depending on the context in which it is used. One possible synonym is "conveyor belts," which are automated systems used in factories to transport materials and products from one area of the factory to another. Another term used to describe factory belts is "assembly lines," which is a system of manufacturing where each worker focuses on a single task along a production line, resulting in increased efficiency. Lastly, "production belts" is also a possible synonym, as it refers to the belts used in factories that move products along the production line to ensure timely and accurate assembly.