Resin trap filter is generally installed at the back end of the negative bed, positive bed, and mixed bed of the ion exchanger. When the quality of the resin is poor and the water pressure disturbance is large (especially high pressure disturbance). When the resin is damaged, the resin will enter the back-end desalted water system and affect the normal operation of other equipment in the system, so a resin trap filter screen needs to be installed.