Melt blown cloth production equipment, detailed explanation of melt blown extruder

Melt blown fabric production equipment, detailed explanation of melt blown extruder

Melt-blown fabric is to use high-speed hot air flow to draw the thin stream of polymer melt extruded from the spinneret hole of the die head, thus forming ultra-fine fibers and collecting them on the condensation net curtain or roller, and at the same time bonding themselves to become Melt blown nonwovens. The width of meltblown fabric from regular manufacturers is generally 1600mm, 2400mm, and 3200mm, and the diameter of the extruder is usually 90mm, 105mm, and 135mm. However, after the epidemic began, the small machines that flocked to them had a smaller width, usually only a few tens of centimeters, and the diameter of the screw was mostly 45mm, 50mm, or 65mm. This kind of machine has low output and low quality, but the cost is cheap and the delivery time is fast. Before the epidemic, the price was only 20,000-30,000. At present, the price of melt blown extruders produced by the mainstream 1600 regular manufacturers in the market is more than 6 million, and the delivery time is more than 2 months.

The production process of meltblown fabric is mainly as follows:

1. Melt preparation

2. Filtration

3. Measurement

4. The melt is extruded from the spinneret hole

5. Melt trickle drawing and cooling

6. Form a net

Overview and principle of meltblown fabric equipment

The melt-blown method is a method that relies on high-temperature, high-speed airflow to spray polymer melts to make them rapidly stretched to prepare fibers. After the polymer chip is heated and pressurized by the screw extruder into a molten state, it reaches the spinneret hole at the front end of the nozzle through the melt distribution channel, and after extrusion, it is stretched by two convergent high-speed and high-temperature air streams to make it thinner . The thinned fibers are cooled and solidified on the mesh curtain device to form a melt-blown nonwoven fabric.

Components of meltblown fabric equipment

Meltblown head, automatic loading system equipment components, ultrasonic cleaning machine, air heater, centrifugal fan, screw extruder, meltblown web forming machine, meltblown offline winding machine, meltblown offline slitting machine and other key equipment.

The core component of meltblown fabric equipment

The spinneret for the melt spinning method is a representative spinneret for the manufacture of synthetic fibers such as polyester and nylon. The thermoplastic resin is heated and melted, and is extruded through the spinneret at a certain speed in air or water. out, cooling and solidification into fiber spinning method. The most core technology is the small nozzle on the spinneret. This nozzle is not only small in size, only 0.15mm, but also has to process complex hole patterns on such a small nozzle, which is extremely difficult to process. The process of nozzle processing requires several months. If the processing accuracy is not high, the melt-blown fabric produced in the end will not meet the corresponding technical requirements, which will affect the protective performance of the mask.

The structure of the meltblown fabric spinneret

The structure of the spinneret is divided into three types according to the shape of the spinneret, which are circular, fan-shaped and rectangular. At present, circular plates and rectangular plates are mostly used at home and abroad. In order to suit different kinds of chemical fiber spinning occasions, circular spinnerets are divided into flat type, flange flat type, flat ring, flange ring, etc.; rectangular spinnerets are divided into flange rectangle and flange groove rectangle, etc. , mostly used for short fiber spinning with more holes.

Melt blown air heater

That is, the pipeline heater consists of two parts: the body and the control system. The heating element is made of stainless steel pipe as a protective sleeve, high-temperature resistance alloy wire, crystalline magnesium oxide powder, and formed by compression technology. The control part uses advanced digital circuits and integrated circuit triggers. , high back pressure thyristor and other components to form an adjustable temperature measurement, constant temperature system, to ensure the normal operation of the electric heater.

Polypropylene material is extracted from petroleum. At present, Sinopec and other enterprises can produce it in large quantities, but the equipment that produces polypropylene into meltblown fabric, especially the core component spinneret, mainly relies on imports. These suppliers mainly include Japan's Kasen spinneret, German Enka, Japan's spinneret and other companies. Japanese suppliers occupy the most important position. The current output of several enterprises is far from meeting the demand of the market. Therefore, the production capacity of the mask ultimately depends on the output of the meltblown fabric production equipment, and the production of the core spinneret nozzle of the meltblown fabric production equipment is very difficult. The processing time takes several months, and the output cannot be greatly increased in a short period of time. Moreover, the production capacity is very limited, which also makes the production of masks can only maximize the use of current equipment and increase production by extending the working hours of the production line.