What is plastic blow molding process?
Blow molding is the forming of a hollow object by inflating or blowing a thermoplastic molten tube called a “parison” in the shape of a mold cavity. The process consists of extruding or “dropping” a parison on which female mold halves are closed. The female mold halves contain the shape of the product to be produced.
What type of plastic is used in blow molding?
The materials used for blow moulding include Polyethylene (High Density, Low Density and Linear Low Density), Polypropylene, Polyethylene-Terephthalate (PET), and PVC.
What companies still make blow molds?
Leading Manufacturers
- Western Industries Plastic Products LLC. Winfield, KS | 620-221-9464.
- Blow Molded Products. Riverside, CA | 951-360-6055.
- Iceberg Molding. Sturgis, MI | 269-651-9488.
- Hi-Rel Plastics & Molding. Riverside, CA | 951-354-0258.
- SPI Blow Molding LLC. Coloma, MI | 269-849-3200.
What are the two types of blow molding?
In general, there are three main types of blow molding: extrusion blow molding, injection blow molding, and injection stretch blow molding. The blow molding process begins with softening plastic, by heating, and forming it into a parison or, in the case of injection and injection stretch blow molding (ISB), a preform.
How much does a blow mold cost?
Molds are not inexpensive; a new mold can cost anywhere between $5,000 – $100,000 depending on the size and complexity.
How does a blow mold work?
With blow molding, a plastic tube is heated and filled with air until it essentially becomes a balloon of hot plastic called a “parison.” A mold is then clamped around this, trapping the plastic while air continues to fill the parison into the shape of your part.
Why is it called a blow mold?
Blow molding has its roots in glass blowing, where a craftsman would heat the glass to its melting point and then blow through a tube to inflate the glass.
What is the best plastic for a mold?
HDPE, LDPE, and PET are all low-cost plastics that resist both moisture and chemicals. LDPE is softer and more flexible than HDPE, which is an opaque material.
What are blow molds made of?
Both blow molding and injection molding involve the use of liquid material — typically plastic — that’s forced into a mold cavity.
Are blow molds worth money?
Smaller blow molds, the kind you can hold in the palm of your hand, might go for $30. Larger ones, nearly life sized, sell for almost $500.
Do they make blow molds anymore?
We’ve got good news and bad news. The bad news is they can be hard to find these days since there aren’t a lot of manufacturers anymore. But the good news is that blow mold manufacturers still exist, and there are quite a few easily accessible retailers who sell them online.
What is blow molding?
Blow molding is the forming of a hollow object by inflating or blowing a thermoplastic molten tube called a “parison” in the shape of a mold cavity. The process consists of extruding or “dropping” a parison on which female mold halves are closed.
What is the most commonly used blow molded plastic?
HDPE is the world’s #1 plastic and the most commonly blow molded plastic material. It’s used in a vast array of products, including bottles for consumer liquids such as shampoo and motor oil, coolers, play structures, fuel tanks, industrial drums, and carrying cases.
What is blow mold pet?
PET is a polyester that is usually injection blow molded into clear containers. While it isn’t impossible to extrusion blow mold PET, it is less common, as the resin requires extensive drying. The largest PET blow molding market is for soft drink and water bottles. PET recycling rates are growing under recycle code 1.
What is the blow molding process of plastic containers?
This final blow molding process is widely used by PET material throughout the manufacturing process of hollowed plastic containers. Similar to the blow molding injection technique, molten polymer flows on a hot runner block into the injection cavity to make the Preform.