Closed cooling towers include a full range of products in mixed flow, side flow, and counter flow types, with a cooling capacity of Q: 50 R T -1 500 R T. They are widely used for closed cycle cooling of various media with a temperature difference of Δ t=3 ℃ -70 ℃, and have corresponding products in the north and south respectively, solving various problems such as high temperature, severe cold, and water quality differences. After continuous product upgrades, the FBH mixed flow model's main products include conventional, large module, and super large module to meet various needs.