When the new machine is used for half a year, due to wear, the gap between the screw of the conical screw barrel and the barrel must be checked every three months, and appropriate adjustments must be made. This is done to avoid excessive clearance leading to a decrease in output, and it may even be the result of screw fracture due to excessive screw swing angle.

The gap between the screw and the barrel is directly related to the quality of the product. If the gap is too large, the shear rate will be low and the plasticizing effect will be poor. Severe material reflux will not only reduce the output, but also make the material stay longer in the barrel and burn easily. If the gap is too small and the shear rate is too large, the material is easily burned, and the screw may even scratch the barrel. Therefore, the gap between the screw and the barrel cannot be too large or too small.

In addition, before measuring the gap between the screw and the barrel, the residual material in the barrel must be removed, and the screw shaft should be close to the distribution box. The reasonable gap should be between 0.20~0.30mm.