Recently, SLMC has finished the transformation of 1300mm/250mpm masking paper coating machine production line for HESHAN RONGDA PAPER CO.. Because of the original coating by blade metering, coating stability is not good. It has affected the quality of paper seriously. After using air knife, the coating quantity can be controlled in the range of 10g/㎡. The coating quality has been greatly improved. Users achieved good returns with less investment, their brand image has been further enhanced.