The sintered felt polyester melt filter element (also called melt filter) mainly uses stainless steel woven mesh or stainless steel fiber sintered felt as the filter medium. Stainless steel woven mesh is made of stainless steel wire, and its pleated filter element features smooth channels, easy cleaning, high temperature resistance (≤500 °C), corrosion resistance, no wire shedding, and long service life. Stainless steel fiber sintered felt is a porous deep filtration material made by high-temperature sintering of stainless steel fibers. The pleated filter element features high porosity, good air permeability, strong dirt holding capacity, and good regenerability. The pleated design increases the filtration area to 5–10 times that of an ordinary cylindrical filter and is used in filtration of polymer melts, oil-water treatment, high-temperature gases, and pharmaceutical media. Service life ≥1 year in chemical industries, ≥2 years in water treatment (shorter in high acidity/alkalinity or high chloride environments).