Die Head and Calibration Sleeve
Both outer layer and inner layer are extruded inside die head. Each material flow channel inside die head is placed evenly. Each channel is after heat treatment and mirror polishing to ensure material flow smoothly. Also die head provides compressed air between both layer.
Calibration sleeve is used to cool inner layer to form smooth and flat pipe inside. Pressure water flows inside calibration sleeve to have good cooling effect. Vacuum is created on calibration sleeve surface when producing big diameter pipe, ensure inner pipe roundness.Read More