HDPE pipe tinea reason: because of the melt flow inside the tube, the velocity difference between wall and wall, when leaving the die, the whole melt and no resistance, the gap between the two to zero. It is the change of the relative motion velocity of each layer that causes the intense oscillation of the melt flow in the die mouth, which leads to the occurrence of this phenomenon!
1. Additives: organic silicone additives (silicone plastic additives) or polymer additives (PPA).
2. The appropriate increase of temperature can also improve melt flow!
Extruded HDPE tube, sometimes because of temperature, sometimes due to the problem of the model of the material, more or less decorative pattern, but sometimes it is the high temperature, the transformation plastic model is still somewhat. One time tried to put the wind ring on the head of the film, or raise it.
3. Select the safe HDPE pipe to determine the appropriate material first. In the past, pipes used to supply water were mainly cast iron pipes. Outdoor main use sand mold cast iron pipe, indoor use is galvanized iron pipe, it can be divided into cold (electricity) galvanizing and hot galvanizing two kinds. Galvanized pipe used as water pipes, a few years later, the tube to produce large amounts of rust scale, outflow of including not only pollute the clean is provided, and mixed with smooth wall not breed bacteria, heavy metal corrosion caused by the water content is too high, cause serious damage to human body health. What's more, the high performance HDPE tube is inexpensive.