Equipment for producing melt blown nonwovens

 In other words, the production process of melt blown nonwovens is: melt the polypropylene chip (fr400-1200) through a screw extruder, spray it into a fibrous shape through the spinneret hole, and under the high-speed (13000m / min) hot air jet, make it subject to strong stretching, forming extremely fine short fibers, which are adsorbed on the net forming curtain, because the fibers can remain relatively small after agglomerating into the net The high temperature makes the fibers adhere to each other and become melt blown nonwovens. Finally, they are rolled and packed.

The devices needed for producing melt blown nonwovens are as follows: 1. Screw extruder; 2. Metering pump; 3. Melt blown device; 4. Receiving net; 5. Winding device; 6. Feeding device. The equipment of continuous production line of melt blown nonwovens is about 6m high, 5m wide and 20m long.

The function of each device is described as follows:

(1) Screw extruder: the diameter of the screw is generally 100-120mm, and the length / diameter ratio is 30. Its purpose is to melt the slice.

(2) Metering pump: it is used for precise metering, control of output and fineness of fiber. It is a gear pump that continuously transports melt to the spinneret.

(3) Melt filter: its function is to filter out impurities in the melt, so as not to block the spinneret hole.

(4) Conveying net curtain: evenly receive and lay the melt blown fiber on the net for forward conveying. There is a suction fan under it to discharge the hot air from the top.

(5) Spinning box: it is the key equipment of melt blown process. There is a long strip spinneret, which is covered with a long row of spinnerets. Generally, there are about 1500 spinnerets per M. The hot air nozzle is installed on both sides of the spinneret, and the hot air orifice is installed below to form a 50B angle with the spinneret, so that after the fiber is ejected, the high-speed hot air is used for air flow stretching immediately, and the fiber is blown off to become superfine fiber.

(6) Feeding system: it is composed of three metering buckets, which are respectively used to measure the white chips, color masterbatch and additives into the mixing mixer below for even mixing, that is to say, it is put into production.

(7) Hot air blower and heater: it provides the temperature and pressure of hot air used in spinning and air stretching. It uses electricity to heat and consumes a large amount of electricity.

(8) The coiler adopts full-automatic coiling to pack the melt blown cloth into rolls. The fiber characteristics of melt blown nonwovens are superfine. The minimum fiber diameter can reach 0.5lm, generally between 1 and 5lm. The finer the fiber is, the better the quality of the melt blown cloth is, but the output is relatively reduced. Because the fiber is superfine, its specific surface area is large and its adsorption capacity is strong, which is the most outstanding advantage of melt blown cloth.