The usage of plastic bottles is everywhere today. From home to shops we need plastic bottles, tank holders, etc. With such huge demand, the importance of the Molding Machine, used in the production of plastic bottles, plastic tanks, containers, etc. We need a good HDPE Molding Machine for the production of plastic bottles. Here’s understanding the entire concept of blow molding in a simplified manner:
The Basic Concept Of Blow Molding –
Blow molding is a process where you blow out molten base material and mold into desired shapes. It is a type of manufacturing process which is used mostly in plastic industries. It is equally used in the glass bottle industry. This technique helps in the formation of a hollow object created by blowing a thermoplastic molten tube or a parison according to the shape of a mold cavity.
Origin of Blow Molding-
Blow molding originated from the idea of glassblowing. Blow molding machine was first produced in 1938 by the duo Enoch Ferngren and William Kopitke. Ferngren and Kopitke sold this to the Hartford Empire company which initiated the blow molding process commercially. Glass was gradually replaced by plastic. This process is now mainly used for the production of plastic bottles.
 Blow Molding Process-
In Blow molding, you have to first begin by melting the base plastic and forming it into a parison or a preform. The parison has a hole in one end from where you can push in compressed air. You need to keep the parison clamped into a mold. Following this you blow air into it. The air pressure blows out the plastic as per the shape of the mold. You follow this with a cooling process. Once it becomes hard, the mold opens. The shaped plastic then ejects out.
 Blow molding is of three types: extrusion, stretch, and injection blow molding.
Extrusion Blow Molding –
This is the largest user of HDPE or High-Density Polyethylene. We use it for productions of bottles, fuel tanks, large holding tanks, etc. Extrusion blow molding can be of two types: continuous extrusion and intermittent extrusion. Intermittent extrusion can be divided into the reciprocating screw, ram, and accumulator parison extrusion.
In the case of Continuous extrusion, you continuously extrude the heated parison. There is a stationary extruder that pushes the molten plastic through the head. It forms a continuous parison.
Injection Blow Molding-
Where you have a requirement for hollow plastic objects in large quantities, you use Injection Blow Molding. Here you inject a polymer into a core pin and rotate core pin in a blow molding station which you then inflate and cool. This process is used for the production of single-serve or medical bottles. You need to follow three steps involved: injection, blowing and ejection.
 Priti International is one such company that runs and supplies HDPE PVC Molding Machine for making bottles. They are one of the best turnkey consultants.