ABOUT Blow Molding
Technology: Blow Molding Services are manufacturing services that form plastics and glass into hollow products such as containers and bottles. Three main techniques used in blow molding are extrusion blow molding, injection blow molding, and stretch blow molding. Although common for making plastic bottles, blow molding is also used to make many hollow flat parts as well, such as tool set kits, in addition to a host of products ranging from medical wares to recreational goods. Blow molding produces parts that can accept variations in wall thickness because air pressure is used to expand softened plastic forms, called parisons, against the inside surfaces of hollow molds. Blow molding can create large items. In most blow molding operations, plastic material is extruded into a molten cylindrical tube which drops vertically between two mold halves. After the mold closes, a nozzle injects pressurized air into molten cylinder, expanding it out to the surfaces of the mold. Other blow molding operations are two stage where performs are made on injection molding machines, often with neck features such as cap threads formed there as well. These preforms are then heated again during the blow molding process and formed.Tooling is less expensive than injection molding molds due to lower pressureExternal threads can be molded inLarge part capabilitiesSuccessful molding requires adjustment and tuning of the parison, knowledge of which many services can offer
Advantages: Blow molding services offer an alternative to injection molding and rotational molding services.
Limitations of Blow Molding ServicesHole making is a secondary stepTight tolerances held on exterior surfaces onlyLonger cooling times than injection molding
Applications: Blow molding services apply to plastic moldings where hollowness is desired/acceptable and only exterior tolerances are of concernBottle and containersSporting goodsPlastic shelters/sheds