Pyörökehräys

Pyörökehräys, also known as ring spinning, is a widely used method for producing spun yarn from staple fibers. It is a continuous process that involves several key stages. First, the fibers are opened and carded to align them into a sliver. This sliver is then drawn and twisted to form a roving, which is a thicker, weaker strand of fibers.

In the pyörökehräys machine, the roving is passed through a series of rollers that attenuate it to the desired yarn thickness. As the roving is being drawn, a spindle rotates rapidly, imparting twist to the fibers. This twist binds the fibers together, giving the yarn strength. The yarn is then wound onto a bobbin.

The primary advantage of pyörökehräys is its versatility, allowing for the production of a wide range of yarn counts and types from various natural and synthetic fibers. It produces yarns with good strength and a relatively smooth surface. However, it is a complex process that requires significant machinery and energy. Compared to other spinning methods like open-end spinning, pyörökehräys generally produces stronger and finer yarns, making it suitable for applications requiring high quality, such as apparel fabrics. The term "pyörökehräys" directly translates from Finnish as "ring spinning," reflecting its mechanical principle.