Negative pressure fans are indispensable ventilation and cooling equipment in livestock farming, especially during summer when mosquitoes, flies, and insects are rampant, and hot weather is detrimental to the healthy growth of animals in breeding farms. Installing negative pressure fans is an effective ventilation and cooling solution. Negative pressure fans, also known as livestock fans, extract indoor air from one side of the pig farm, creating a negative pressure indoors. Typically, there are air inlets on the opposite side of the negative pressure fans, and these inlets should not be placed on the downwind side. Fresh outdoor air flows into the room through the inlets, forming a stable airflow zone for ventilation and cooling. This is the working mode of negative pressure fans, which can typically complete an air exchange within a few minutes.

Galvanized sheet negative pressure fans are generally divided into galvanized sheet negative pressure fans and fiberglass reinforced plastic (FRP) negative pressure fans. Galvanized sheet negative pressure fans are cheaper than FRP ones, but FRP negative pressure fans offer corrosion resistance. In ordinary workshops, galvanized sheet negative pressure fans are commonly used, while in corrosive environments such as chemical plants, pig farms generally opt for FRP negative pressure fans.

Negative pressure fans are usually used together with cooling wet curtains, forming a water curtain fan cooling system. In practice, wet curtains and negative pressure fans are installed on opposite sides of the workshop. This setup provides high air volume, long air delivery distance, and顯著 ventilation and cooling effects.

Pig farms release large amounts of ammonia and particulate matter. Therefore, providing adequate ventilation is crucial for maintaining the health of the pigs.