The reason is that the melt flow in the cylinder, the flow between the cylinder wall and the inner wall of the difference, when leaving the die, the whole melt and no resistance, the gap between the two becomes zero. It is the relative movement of the layers of the change, causing the mold at the melt flow of intense oscillation, leading to the occurrence of such phenomena!
1, add auxiliaries: like organic silicone additives (silicone plastic additives) or Fu Fu polymer additives (PPA).
2, the appropriate increase in temperature can also improve the melt flow!
Squeeze HDPE pipe, and sometimes because of temperature, and sometimes because of the type of raw material problems and more or less patterns, but sometimes it is to increase the temperature, change the plastic model or how much. There have been tested on the membrane head of the air ring overhead, or that elevation.
3, choose the rest assured HDPE pipe first to determine the appropriate material. In the past, the pipes used for water supply were mainly cast iron pipes. Outside the main sand cast iron pipe, indoor use of galvanized cast iron pipe, which can be divided into cold (electric) galvanized and hot galvanized two. Galvanized pipe as a water pipe, the use of a few years later, the tube produces a lot of rust, the outflow of yellow water not only pollution sanitary ware, and mixed with non-smooth wall breeding bacteria, rust caused by high levels of heavy metals in water, serious harm to human health. More importantly, the performance of such a superior HDPE pipe, the price is not expensive.
Drainage HDPE pipe is the traditional PVC, pig iron pipe drinking water pipe replacement products. Drainage pipe must be able to prohibit the inevitable pressure, usually choose the machine function is better, large molecular weight PE resin, such as HDPE resin, and LDPE resin pressure, tensile strength is low, poor steel, forming the proportion of poor stability when polished , And the connection problem, not suitable as a drainage pressure pipe material.
From the high temperature function, PE pipe with the temperature rise of its function to quickly reduce the use of temperature of ± 60 ° during which the general use of cold water for the main, mainly for the drainage pipe on the main road, which after the home Of the drainage pipe selection, will choose PPR pipe.
PE pipe light weight, good elasticity, high impact resistance, non-toxic, cheaper unit price, low temperature performance is better, is now municipal construction, real estate, factories, water conservancy construction and other water supply and drainage pipeline must.
HDPE is a thermoplastic polyolefin produced by copolymerization of ethylene. Although HDPE was introduced in 1956, but this plastic has not yet reached a mature level. This common material is also constantly developing its new uses and markets. The thermoplastic resin. The appearance of the original HDPE was milky white, in a slight cross-section was a certain degree of translucent. PE has excellent resistance to most of the characteristics of life and industrial chemicals. Certain types of chemicals can produce chemical corrosion, such as corrosive oxidants (concentrated nitric acid), aromatic hydrocarbons (xylene) and halogenated hydrocarbons (carbon tetrachloride). The polymer is not hygroscopic and has good resistance
PE can be manufactured with a wide range of different processing methods. Including extrusion such as sheet extrusion, film extrusion, pipe or profile extrusion, blow molding, injection molding and rotomoulding.
HDPE pipe is the traditional steel pipe, PVC drinking water pipe replacement products.
The roughness coefficient of the HDPE pipe is between 0.009 and 0.01, which is much smaller than the roughness coefficient of the reinforced concrete pipe (0.013-0.014). It can be seen that compared with the reinforced concrete pipe with the same diameter, In the traffic will be greater. For the municipal drainage works, through the application of HDPE off, can effectively increase the amount of emissions, thereby reducing the construction of sewage pumping stations, reducing the cost of urban sewage treatment.
HDPE pipe is a flexible pipe, in its interface is usually used in a flexible connection, it has a good sealing performance, and has a strong ability to adapt to the pipeline foundation uneven settlement, anti-leakage is very strong. Compared with the clean concrete pipes used in the traditional municipal drainage works, the HDPE pipe is flexible on the material and foundation, and it can play an effective anti-underground pollution because of its good sealing and good anti-leakage.
HDPE pipe and the traditional reinforced concrete pipe is different from the use of high-density polyethylene inert materials, so a variety of chemical have a strong corrosion resistance, so in high acid, high alkali or sewage discharge has a good effect The In the underground use, HDPE pipe can be used for more than 50 years, while the reinforced concrete pipe is susceptible to corrosion in the soil, usually in the service life of about 20 years. It can be seen, compared with the traditional reinforced concrete pipe, HDPE has a longer or useful life.