Commercial refrigerators are generally divided into three categories: commercial refrigerator (also known as beverage cabinet), commercial freezer (also known as cold food cabinet) and kitchen refrigerator, with a volume ranging from 20L to 1600L. The temperature in the commercial refrigerator is 0-10 degrees, which is widely used in the storage and sales of various beverages, dairy products, fruits and flowers. According to the door opening mode, it is divided into vertical (front opening), top opening and air curtain type. The vertical freezer is divided into single door, double door, three door and multi door. The top opening has barrel shape and square shape. The air curtain type includes front opening and top opening. China's market is dominated by vertical commercial refrigerators, accounting for more than 90% of the total market capacity.