Mixing is an important process in feed production, which provides guarantee for the production of qualified finished products and is one of the important guarantees for feed safety. The mixer is the key equipment of the mixing process. The scientific design and reasonable selection of the mixer are closely related to the product quality and production efficiency of the feed. "Chapter 4" in "License Conditions for Feed Production Enterprises" and "License Conditions for Mixed Feed Additives Manufacturers" stipulates the following provisions on the mixing uniformity variation coefficient of mixing equipment: solid additive premixed feed, mixed feed additive manufacturing enterprises The mixing uniformity coefficient of variation CV of the mixer used is less than 5%, and the mixing uniformity coefficient of variation CV of the mixer used in the production enterprises of concentrated feed, compound feed, and concentrate supplement feed is less than 7%. At present, the mixers used in domestic feed production are basically single-shaft double ribbon mixers, double-shaft paddle mixers, and single-shaft paddle mixers.