Types Of Blow Molding Machine And The Benefits Of Buying Used Blow Molding Equipment

By Author: ADVAN
Total Articles: 389
Comment this article

What Is Blow Molding?

Blow molding is a manufacturing process for forming thermoplastics into hollow objects. Soft drink bottles, shampoo and conditioner bottles, oil bottles, and water containers are all examples of thermoplastics that have been blow molded into the shape of a receptacle.

What Are The Types of Blow Molding?

Extrusion Blow Molding (EBM) is by far the most common form of blow molding. The process begins by heating the parison, which is a hollow tube through which compressed air can be routed. Then the thermoplastic material is heated to make it pliable. The material is placed inside the mold in the blow molding machine and compressed air forces the thermoplastic material into the shape of the mold in a fraction of a second. The material is then cooled at a controlled rate, where it hardens in the shape in which it was formed.

Compression Blow Molding (CBM) is also common and is used to mass produce plastic automotive parts. The process begins by heating the plastic material to make ...
... it pliable and securing it to the bottom half of a mold in the blow molding machine. The top half of the mold is then pushed into the bottom half of the mold, forcing the plastic material to take the shape of both sides of the mold. This too happens in a fraction of a second. The material is then cooled, at which point it hardens and is ejected from the bottom half of the mold by way of an ejector pin.

Injection Blow Molding (IBM) is similar to Extrusion Blow Molding but is used in applications where more precision and detail is required. The hot material is kept inside the pin, which is inserted into the mold, and then blown into the shape of the mold out the pin. The blow molding equipment is different to that of extrusion or compression blow molding.

Injection Stretch Blow Molding (ISBM) takes the process of injection molding and then, following a few days rest, reheats the material and blows it into another mold where it takes its final shape.

Advantages and Disadvantages of Blow Molding

Advantages

With all types of blow molding, the process allows for quick production and very high volumes of product to be produced in a short time. Although weaker than other types of plastic manufacturing, blow molded product is the ideal strength for drink bottles and containers of all shapes and sizes.

The cost of producing tools and dies for this form of manufacturing is very low, and the process allows for complex molding, including handles as a part of the design.

Disadvantages

The equipment itself, however, is very large and requires a lot of floor space. Designs are limited to hollow parts, and parts produced from this method are low strength. And, of course, blow molding is limited to thermoplastics.

Why You Should Buy Blow Molding Machine Used

The most obvious benefit to buying used blow molding equipment is that there is a lower upfront cost than buying new. This means you avoid initial depreciation costs. This has a knock-on effect of lower insurance rates for the lifetime of the equipment, and many times there is a wider selection of equipment available on the used market.