Types of Plastic Moulding How to Choose the Right Type!

Does this sound familiar? You’ve just launched your new product! Your business is growing steadily and now that you need to hire a professional designer – which means preparing product design guidelines is important!

But how do you begin this journey as a designer? There are plenty of factors to take into account as you design, and here we will outline five types of plastic moulding every designer should know about.

1. Injection Moulding

Injection moulding is the process of manufacturing plastic parts using a mould. This involves injecting melted polymer into an exact replica of the finished part, usually made out of tool steel due to its resistance to high temperatures caused by melting polymers.

Injection moulding is commonly used for thermoplastic materials such as polyacetal (POM), nylon, polycarbonate (PC), polypropylene (PP), acrylonitrile butadiene styrene (ABS) and high impact styrene acrylonitrile (HIPS).

Injection Moulding Process

The Injection Moulding Process involves placing raw materials into a hopper and melting their consistency in a heating chamber called a heater barrel. The melted plastic then passes through an injection unit where it is forced into the mould cavity under pressure from a hydraulic ram called an actuator. The ram pulls back once the plastic has been injected into the cavity, ejecting any excess material left in the nozzle. Once cooled down and solidified, the finished product is ejected from its mould by an ejector pin or punch mechanism that pushes the mould open and releases the part.

The main advantage to this type of manufacturing system is that it allows for fast production rates while using relatively low energy consumption levels due to its high production volume per cycle time period.

2. blow moulding

Plastic blow moulding is used for the production of large hollow or hollow-bodied products with a large connecting surface area between the inside and outside walls of a part.

Blow moulding is a method used to manufacture bottles and other containers. It begins with an airtight preform made of either raw plastic or glass that contains a hollow cavity filled with molten material that cools and solidifies into the desired shape of the bottle or container. After heating the preform until it loses its shape, another one is replaced and the process continues until all cavities have been filled.

Blowing moulding is a process in which a heated blow mould is placed over a plastic pellet. As the pellet melts and flows into the cavity of the blow mould, cooling and hardening takes place until its desired shape is achieved. Once opened, one can admire the finished product!

Blow molding offers numerous advantages.

One of the most cost-effective manufacturing processes, this makes it ideal for high volume runs.

It can manufacture very large products, including those too big to fit in other machines (like bottles). Furthermore, this process is ideal for creating complex shapes like sports balls or toys with moving parts.

3. Extrusion moulding

Extrusion moulding is a plastic processing method that uses a material to push through a die in order to create a consistent final product. The type of material used depends on the end result, but many extrusion processes use molten thermoplastics.

In this process, a solid or semi-solid plastic is forced through an opening called the die. This creates a hollow tube of plastic that can be cut into different lengths or shaped into various shapes.

Extrusion moulding has many advantages over other methods of plastic processing, including:

Consistency

this method produces consistent results because it uses the same amount of pressure and speed for each part. It also ensures that all parts are exactly the same size and shape as one another.

Low cost

because extrusion requires less labour than other forms of plastic processing, it can be done quickly and cheaply. This makes it ideal for mass production environments where large volumes of parts are needed quickly and cheaply .

Versatility

extrusion can be used to create a variety of shapes and sizes, including: pipes, rods, bars, tubes and sheets. This makes it flexible enough to produce a wide range of products.

Durability

because extruded plastic is hard and rigid, it can be used in applications where strength is important. This makes it a good choice for components that will be subject to stress or impact, such as: handles, hinges and brackets.

4. Compression moulding

Compression moulding is a manufacturing process in which two or more materials are heated and pressed together to form one solid mass. It has similar characteristics to injection molding, except that compression molding involves an upper die with cavities and a lower platen.

The upper die is typically constructed out of steel, while the lower platen can be constructed out of either steel or aluminum. When heated and forced together, molten plastic material will seep out between them creating a uniform thickness between both dies.

Plastic resin is injected into the die cavity as it’s compressed by the upper die and lower platen. This creates high pressure at every point on the resin surface, producing a strong finished product with few air bubbles present.

5. Rotational moulding

Rotational moulding is a manufacturing process that uses an array of hollow plastic molds to create objects by injecting heated plastic into the mold. These molds are mounted onto a rotating platform, which turns in order for the item to be formed.

Compression moulding is a manufacturing process in which two or more materials are heated and pressed together to form one solid mass. It has similar features to injection moulding, except that an upper die with cavities and a lower platen are employed.

The upper die is typically constructed out of steel, while the lower platen can be composed either of steel or aluminum. When heated and forced together, molten plastic material is squeezed out between them creating a uniform thickness between both dies.

takeaway

Knowing what type of plastic to work with can make all the difference between a successful project and a failed one. Knowing more about the different types of plastic that can be used for various projects, then, is helpful for designers and engineers of all stripes. And with so many options available, whether it’s in the form of resin or non-resin products, it helps to know what the differences are between each option and how to decide which one will be right for your needs.