In order to further improve the opening quality of fiber raw materials and improve the quality of yarn, the development direction of the opening process is to improve the form and structure of the feeding mechanism, and widely use spur rollers, needle punches or needle rollers. Comb machine parts, improve the opening degree of the fiber block, improve the structure and uniformity of the semi-finished products; strengthen the pre-opening of the fiber raw materials, during the opening process, use more free blows, try not to use holding blows; apply airflow and other The method of opening and removing impurities, to avoid fiber damage and impurity rupture, in order to reduce the resulting yarn defects.

It is reflected in the quality indicators and falling objects of the second half of the product (fiber roll or fiber layer) after opening. This includes:

Types and quantity of impurities and defects in semi-finished products

Structure and uniformity of semi-finished products

Short fiber content in semi-finished products

The opening degree of the fiber block is expressed by the average weight of the fiber block, the weight per unit volume or the final velocity of free sedimentation in the air, etc.

The amount of spinnable fibers in the fall