Roots blower Melt blown Cloth

Meltblown fabrics and non-woven fabrics are two similar things. Meltblown fabric belongs to non-woven fabric and industrial textiles. The main raw material of non-woven fabric is polypropylene particles. It has the characteristics of light weight, moisture-proof and good air permeability. It is mainly used in packaging bags. Melt blown cloth is mainly made of polypropylene, which is mainly used to make masks and heating products. Recently, some customers have called to inquire about the roots blower for meltblown cloth, but they don’t know the configuration of Roots blower. Let’s learn about roots blower used in meltblown cloth production.

We know that the melt blown cloth is the core filter material of the mask, which is mainly determined by the filtration mechanism of the melt blown filter material, which is mainly divided into mechanical barrier and electrostatic adsorption.

1、 Mechanical barrier

Mechanical barrier has the following conditions:

1. The droplets larger than 5um in the air can be blocked by the filter material.

2. When the micro dust diameter is less than 3 um, the micro dust is mechanically intercepted by the fiber layer in the curved channel of the mask filter material.

3. When the particle size and air velocity are both large, the particles are captured due to inertial collision with the fiber; when the particle is small and the flow velocity is low, the particles are captured by Brownian motion impacting on the fiber.

2、 Electrostatic adsorption

Usually, in the production process of melt blown fabric, electret treatment is used to make the non-woven fabric carry more static electricity and have electrostatic adsorption effect. Electrostatic adsorption refers to the capture of dust bacterial viruses through the Coulomb force of charged fibers when the fibers of filter materials are charged.

There are two ways to improve the charge storage capacity of Electret Materials

1. By improving the crystallinity and mechanical deformation of the material, the structure of the material is changed, and the slender hole channel is formed to prevent the charge drift.

2. An additive with charge storage property is introduced to generate charge trap to capture charge.

The melt blown Roots blower uses the tiny gap between the casing and the impeller to force the air out, without lubricating oil in the cavity, so the output air does not contain oil, and the melt blown cloth sprayed does not contain impurities or odor. The pressure range of the Roots blower is 10-100KPA, and the general optimal melt blown cloth pressure requirement is 58.8KPA, because it is just suitable for the melt blown machine. Moreover, the efficiency is much higher than that of air compressors under low pressure conditions below 100KPA, and its simple internal structure is also more convenient to maintain than air compressors.

The influence of throttle hole, damping mechanism, air gap in components, angle of spinneret and other factors on the drafting flow of melt blown cloth will increase a lot of flow resistance, consume the energy of air flow, and attenuate the pressure and speed of air flow, which will affect the selection and configuration of Roots blower. When this resistance is large, it is necessary to select high pressure roots blower to meet the process requirements!