The multi ridge method adopts rectangular spinneret, each spinneret is 45cm long, and is divided into seven spinneret hole areas. When polypropylene is used as the raw material, when the linear density produced is 0.17 tex (1.5 denier), each spinneret hole area has 150 holes: linear density is 0.33~0.56 tex (3-5 denier), 100 holes: linear density is 0.56~1.71 ex (5~15 denier), and 35 holes.

The chip silo enters the screw extruder, and the metering pump and spinneret spit out the melt trickle. Under the blowing of cooling air, the filament is cooled. Then the filament enters the air flow drafting device, and the high-pressure air accelerates the filament to realize the purpose of drafting orientation. The pressure of high-pressure air can reach as high as 20-22 atmospheres, the drafting speed can reach 3500-4000mm/min or even higher, and the tensile strength ratio can reach over 1:200. After such drafting, the strength of the filament meets the requirements. The nozzle of the drafting device is easily damaged due to the action of high-pressure air and friction with the filament, so wear-resistant materials must be used.

After being stretched, the filament reaches the end of the stretching pipeline, which is shaped like a horn. The high-pressure airflow suddenly diffuses and decelerates here, producing an aerodynamic coanda effect, causing the fibers to separate from each other.

The filament output from the bell mouth of the stretching pipeline is very fluffy, approaching a single state, and its movement speed has also decreased to 20200m/min. Due to the air suction effect of the air suction device below the condensing mesh curtain, the filament is laid into a mesh on the condensing mesh curtain.

Condensed mesh curtains generally use metal wire mesh or polyester filament woven mesh. The bell mouth of the stretching pipeline can be arranged at a certain angle or parallel to the direction of movement of the condensing mesh curtain. Through proper arrangement, there can be no obvious contact marks between the webs formed by each spinneret, so as to improve the evenness of the webs. The multi bucket method can produce fiber mesh with a quantitative range of 20-2000g/m2. By controlling the movement speed of the condensing mesh curtain, different fixed weight fiber meshes can be obtained. The minimum width of the fiber mesh obtained by the multi ridge method is 900mm (one spinneret), and the maximum width can be more than 5m.

After forming the mesh, pre reinforcement should be carried out immediately. Low weight fiber mesh generally adopts thermal reinforcement, while high weight fiber mesh adopts needle reinforcement pre reinforcement. After pre reinforcement, the main reinforcement method should be selected according to product requirements.

The production speed of the multi bucket method is high, and when the fiber mesh quantity is 80g/m2, the output speed is 30-50m/min. The aspect ratio of the fiber mesh produced by the Duokan method can reach 1.5:1.