Surface treatment of pipe fittings→feeding→pressing by high-pressure water pump→sintering→dressing→inspection. The surface treatment requirements are the same as those of the tube tight lining method. Feeding, select the polytetrafluoroethylene resin produced by the suspension method, sieving through a mesh sieve to make it appear loose, and evenly charge it into the material cavity. For compaction, connect the powder-filled pipe fittings, the mold and the high-pressure water pump, and press under appropriate water pressure to compact the powder. Sintering, remove the mold, and send the pipe to the sintering furnace for sintering after drying. After trimming and sintering the pipe fittings, use a hand-held grinding wheel to smooth the uneven or angular flange surface. The inspection is the same as the tight-lined pipe inspection method.