Blow Moulding

Blow molding is a manufacturing process that creates hollow plastic parts or other hollow shapes, such as glass bottles. It's a common technique used in the production of consumer and industrial products, including: 

• Containers: Bottles for food, beverages, pharmaceuticals, and cosmetics 
• Automotive: Ducting 
• Industrial: Tubs and drums 
• Medical: Lightweight, easy-to-sanitize products 

The blow molding process involves:

1. Heating: Melting the plastic
2. Inflating: Also known as parison or preform, this is the plastic tube that's heated and inflated
3. Molding: Cetakan are placed on either side of the preform, and air is introduced to expand the plastic and make the walls thinner
4. Cooling: The product is cooled and removed from the mold
5. Finishing: The product is cleaned and prepared for final use The process of Extrusion Blow Moulding Machine | Central

There are several types of blow molding, including extrusion, injection, and injection stretch. The main difference between types is how the preform or parison is produced. 
Blow molding has several advantages, including:

• Cost
• Molds and manufacturing are usually less expensive than other plastic manufacturing methods.
• Custom shapes
• Extrusion blow molding can create intricate, custom shapes with precise sizes, finishes, and wall thicknesses. 

However, there are also some disadvantages, such as:
Wall thickness: There are limits to how much the wall thickness can be varied.
Recycling: Products made from thermosetting polymers can be harder to recycle.