Polypropylene BCF yarn, commonly known as polypropylene expanded yarn, polypropylene carpet yarn, BCF is the abbreviation of expanded continuous filament, and does not refer to expanded continuous filament produced by one-step process. Polypropylene BCF filaments can be made in several different processes.
Lin Jiaxiao gives you a brief introduction to the three process of making polypropylene BCF yarn:
The first one: one-step method: continuous spinning, stretching, deformation, winding process
The second method: two-step method: spinning and drawing combined → wire deformation or spinning winding → wire drawing deformation
Third: Three-step method: spinning and doffing → wire drawing → deformation
The one-step process for the continuous production of polypropylene BCF yarns requires the simultaneous use of three screws of the same specification to extrude the melts of the different colors required for the three requirements, and then pass through the distribution pipe to the spinneret, allowing each filament to be made up of three different The color of the silk is assembled, and finally the polypropylene BCF filament is made by continuous tensile deformation.
The two-step or three-step process is basically similar in that a winding bobbin is set to one color, and then the three color bobbins are combined and stretched to form a polypropylene BCF yarn.
Although there are three kinds of processes in foreign countries, the two-step process is used more.