What is a plastic extrusion process in a step-by-step guide?
2020-12-24What are the pros and cons of plastic extrusion molding?
Nowadays we can see a great innovation and versatility in plastic products. All these plastic products are making our lives better and safer like never before. Moreover, these products are adding extreme comforts in our daily lifestyle. But all these useful plastic objects are just because of plastic extrusion.
In fact, extrusion is a very effective way to produce several shapes using many different materials. Further these shapes and products are helpful in both industrial and domestic industries. But here we are discussing the plastic products that have created by extrusion.
If we consider at the uses of modern plastic products, we will acknowledge that,
- our modern life;
- and all its comforts;
are only possible because of these products. You can see them in your smartphones, computers, television and several other electronic devices. Moreover, there are countless uses and benefits of plastic products which have created by plastic extrusion.
In this guide, we will explain you about, extrusion, plastic extrusion and its different types of processes. Additionally, you will see the pros and cons of extrusion by using material of plastic.
So, let’s dive in!
What do you mean by the word extrusion?
Basically, extrusion is a manufacturing process which creates shapes by forcing the melting material into a specific die. This die helps to create objects with several particular profile and shape. As the melting materials pass via this die, it changes its shape according to the shape of die.
The process of extrusion is highly systematic. Further, it is almost similar for materials of rubber and plastic. The only difference is between their operating temperatures and some other necessary deference. But all the basic rules and principles are same in all extrusion process.
Today, manufacturers are widely using several metals, plastic and ceramic materials in extrusion to get the desired shapes.
Now let’s start to know deeply about plastic extrusion.
What is plastic extrusion?
In this type of extrusion, manufacturers use plastic as the base material. In fact, plastic extrusion helps to get the several different types of shapes. It is very easy to get simple to complex designs by using a die. Actually, in extrusion, manufacturers put melted plastic and then resolidified it.
So, they use thermoplastics in getting their final designs. Because only thermoplastics have ability to undergo extrusion. This type of plastic has many good properties. Because it is good for recycling,
- numerous post-consumer goods;
- scrap pieces, etc.
with the help of plastic extrusion, manufacturers create consumer as well as industrial goods. It is very easy to get simple to complex designs by using a die.
Different types of products which you can get from plastic extrusion
In fact, plastic extrusion helps to get the several different types of shapes. Moreover, it can produce different items, such as,
- tubing or pipe;
- fencing;
- window frames;
- plastic sheeting and films;
- weatherstripping;
- deck railing;
- wire insulation;
- solid shapes;
- thermoplastic coating and many, many more.
Which kind of plastic is ideal for plastic extrusion?
Actually, manufacturers use commodity plastics in plastic extrusion because they are suitable for the majority of applications. Additionally, they are account for almost 90% of all thermoplastic use.
Basically, these plastics are very easy to process. Moreover, they are very easily available as well as extremely cost effective to use for your extruded products.
Its most common examples are:
- polyethylene (PE)
- polypropylene (PP)
- polyvinyl chloride (PVC).
How does plastic extrusion work?
You can get several different forms of plastic products by the help of extrusion. But the process which takes place to get these different objects is same whether these products are,
- small;
- simple or complex.
Furthermore, they all start with the same material, like, resin and in the same place. It is actually very easy process. We can easily describe the whole process in just few words. For example, in plastic extrusion, the selected plastic beads are melted then filtrate to get uniform consistency.
In the next step this melted resin have pushed into die for specific shape. Hence, the required shape has to cool down for a while and your final product is ready now. Further, these plastic items are helpful to use in,
- building materials;
- industrial goods;
- countless consumer objects and so on.
Although this process of extrusion by using plastic is simple but it is highly technical also. So, we have decided to describe you, the whole process in a step-by-step guide. Let’s take a deep look!
Step # 1:
In the first step of plastic extrusion, manufacturers load raw plastic materials, such as
- pellets;
- powder;
- granules;
inside a hopper. Next, this resin has fed into a long heated cylindrical chamber. This long heated cylindrical chamber has known as an extruder.
With the help of a revolving screw, it moves through this chamber. In fact, several extruders may have one or two revolving screws. But it totally depends on their particular designs.
For a best shape of plastic profile, it is very important to design the die in a smooth way. Because melted resin should flow smoothly to get the final shape of the object. Actually, for getting best products, the consistency in the flow is extremely critical.
What are the types of plastic extrusion process?
Basically, there are different types of extrusions in plastic. And it totally depends to the types of products which you want to get through plastic extrusion. These different types of plastic extrusion are:
- Film or sheet extrusion
- Blown film extrusion
- Over jacketing extrusion
- Tubing extrusion
- Extrusion coating
Famous uses of plastic extrusion
The manufacturing companies are rapidly using extrusion molding to produce consistent cross-section products. Furthermore, if we consider its uses in our surrounding, we can easily find these products, like,
- rain gutters;
- PVC pipes;
- automotive trim;
- vinyl siding;
- windshield wiper and much more.
What are the pros and cons of plastic extrusion?
In fact, extrusion molding process offers several advantages to the manufacturers. As well as it has some disadvantages also. So, here we are giving you some pros and cons of plastic extrusion.
Pros | Cons |
This process is actually low in cost than other molding processes | It provides you limited variations in designs |
It is highly efficient | Your plastic products can little expand even after final design configuration due to unpredictable expansion |
It allows you to some post-extrusion manipulations | Actually, there is a problem of die swell |
You can produce complex shape with great flexibility |
Conclusion:
Basically, plastic extrusion has ability to provide high volume output with continuity. Hence, this benefit makes this process extra economical method to produce plastic products. Moreover, its cost of tooling is extremely low. Plastic films, tubing, piping are only some examples of its products.
However, in this modern age, its uses are countless due to its flexibility and effectiveness.