PE has many USES, such as wires, cables, hoses, pipes and profiles. The pipe range is used for thick wall black pipe which is used in the small section yellow pipe of natural gas to 48in diameter for industrial and urban pipe. A large diameter hollow wall that works as an alternative to concrete for rainwater and other sewer lines is growing rapidly.
Sheet and heat forming.
The thermoforming lining of many large picnics is made of PE, which is resilient, lightweight and durable. Other sheets and thermoforming products include fender, tank lining, pan - basin protective cover, transport case and tank. A large number of rapidly growing film applications are the mulch or the bottom village, which is based on the toughness, chemical resistance and impermeability of MDPE.
More than one third of hdpe-sold in the United States is used for blow molding. These range from bottles of bleach, oil, detergent, milk and distilled water to large refrigerators, car fuel tanks and canisters. The characteristics of the blow molding grade, such as melt strength, ES-CR and toughness, are similar to those used for sheet metal and thermal forming. Therefore, similar grades can be adopted.
Blow molding is usually used to make smaller containers (less than 16oz) for packaging medicines, shampoo and cosmetics. One of the advantages of this process is that the production of the bottle automatically goes to the corner and does not need to be processed in the late stages like the general blow molding process. Although there are some narrow MWD grades for improving surface finish, general use is wide to wide MWD grade.
HDPE has numerous applications ranging from reusable thin-walled drink cups to 5-gsl cans, consuming 1/5 of HDPE produced in China. The general melt index of injection grade is 5 ~ 10, which has a low level of flexibility and a higher liquid grade with machinability. USES include daily necessities and food thin-walled packaging; Resilient, durable food and paint can; High environmental stress cracking applications, such as small engine fuel tanks and 90-gal garbage cans.
The material used in this process is generally crushed into powder, which melts and flows in the heat cycle. Rollers use two types of PE: generic and cross-linked. Generic MDPE/HDPE generally has a density range of 0. 935 to 0. 945g/CC, with narrow MWD, makes the product have high impact and minimum warpage, and its melt index range is generally 3-8. Higher MI grades are generally not applicable because they do not have the impact and environmental stress cracking resistance of rolling plastics.
The high performance roll-plastic application system utilizes its unique properties of chemical crosslinked grade. These grades are in the first stage of the molding cycle, which is good in fluidity, and then crosslinked to form its excellent environmental stress cracking and toughness. Wear resistance and weather resistance. Cross-linked PE is only suitable for large containers, ranging from 500-gal transportation of various chemical storage tanks to 20,000 -gal agricultural storage tanks.
PE film processing is generally used for ordinary blown film processing or flat extrusion processing. Most PE is used for film, general low density PE (LDPE) or linear low - density PE (LLDPE) are available. HDPE films are generally used for superior tensile and excellent impermeability. For example, the HDPE film is often used in merchandise bags, grocery bags, and food packaging.