The sudden COVID-19 epidemic made the professional term "melt blown cloth" known to the public overnight, and the melt blown industry also developed rapidly. At present, China has become the country with the largest production capacity of melt blown fabrics and the most comprehensive equipment category in the world, and has mastered mature full process equipment design and manufacturing technology, and has exported a large number of melt blown equipment and products to the world. However, the melt blown nonwoven process is difficult to control and has high technical content. The rapid development of the industry has triggered an urgent demand for talents and technology in the industry; Especially after the demand for anti epidemic materials has ebbed, facing the fierce market competition, the industry enterprises need to work hard on talent training, technology, product development and market development.
Because the melt blown spinning process is unsteady, the thickness of fibers at different positions is different. However, no matter in the field of view of electron microscope or fiber analysis instrument, it is basically impossible to see the end with fiber. If the melt blown fiber is really a short fiber, it should be visible, which also proves that the fiber is continuous.
The viewpoint of continuous fiber can guide the production practice correctly, explain the abnormal phenomena in the production process visually, and provide clear ideas and countermeasures for solving process problems.

High speed photography of melt blown spinning fibers

Exxon melt blown process is the current mainstream melt blown production process, also known as single hole spinning process. Almost all melt blown nonwoven products are produced by Exxon melt blown process. The feature is that the spinneret plate is an isosceles (or equilateral) triangular component, the spinneret holes are arranged on the top of the triangle, and there is only one row of spinneret holes. The high temperature and high speed air flow is used for drafting, and the draft air flow is ejected from both sides of the spinneret holes at a certain angle. Compared with other melt spraying processes, the fiber distribution is narrow.

Production process of melt blown nonwovens

In addition to the Exxon melt blown process, there is also a melt blown nonwoven production technology in which the spinneret holes are distributed in multiple rows and columns. Each spinneret hole is composed of two concentric tubes nested together. The spinning melt is ejected from the central tube, and the drafting air flow is ejected from the annular channel centered on the melt pipe. This process is developed by the American Biax Fiber Membrane Company, called the Biax process.

Production technology of melt blown nonwovens with multi row holes

Melt blown production line compatible with single row hole and multi row hole processes

In the simple melt blown production line, the roller receiving mode is often used, and the roller receiving mode can be divided into single roller and double roller receiving modes. The number of receiving rollers has a great impact on the product performance. It is also the roller receiving. The products receiving with double rollers have a relatively loose structure.