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What Plastic Fabrication Works Best

The use of  plastic molding in the manufacturing of a wide range of plastic products is increasingly on the rise. This is due to the numerous advantages and benefits that come with using these processes as compared to traditional forms of plastic manufacturing.

In the current world, plastic products are used in almost every industry, from the automotive, agricultural aviation industries among many others. As a result, people are always looking into improving plastic manufacturing, with processes that offer high quality of production at an affordable cost.

Examples of plastic molding processes include injection molding, blow molding and rotational molding or rotocasting.

Each molding process has its pros and cons, but so far rotational molding has outweighed the others in that it presents more advantages than disadvantages. Let’s look at each process and the benefits it has over the others:

Types of Plastic Molding Processes 

Rotational Molding

It is a process for creating stress free hollow products. Heated plastic is rotated inside an oven to take the shape of the mold, then cooled to give a finished product. The process therefore offers a lot of options in terms of production and design. It is possible to create hollow products of any size, shape, color etc at quite an affordable tooling cost. The process is ideal for creating a wide variety of products such as water tanks, car parts, complex medical products like syringes among many other products that have complex shapes.

Advantages of Rotational Molding

Durability – The products have uniform wall thickness, eliminating the risk of having weak parts especially in large tanks.

Size – It make it possible to manufacture products of any size. From a tiny ping pong ball to a large tank that can hold thousands of gallons of water.

Design – There is no limit to the design options when it comes to rotational molding. One can opt for very complex designs to fit specific purposes. There is also the option of making the product more durable by opting for ribbed designs.

Strength – The process allows for metal inserts to be placed in the mold when manufacturing, so the end product is very strong and resilient.

Low tooling costs – It is quite affordable for both the manufacturer and consumer because the upfront costs are lower when compared to injection molding.

Low production costs – The cost for making a mold is inexpensive and once created it can be adjusted to suit various needs. This flexibility makes it cheaper than injection molding.

Surface finish – Rotation of the heated plastic ensures that it takes the texture of the mold, allowing for lots of choice on how the finished product will look.

Decoration – With rotational plastic molders, one can add graphics, logos and other patterns, which means the finished product will have a beautifully permanent and vibrant imprinted feature. This is much better than the traditional process of adding logos on finished products.

Disadvantages

Longer process – The manufacturing process takes a relatively longer time. This is because the rotation process is slow to ensure that the raw material coats the mold evenly, thus needs a lot of patience to wait until the finished product cools.

Powder form – The raw material needs to be in powder form, which incurs extra costs when grinding the plastic polymer.

Limited – The process is only limited to raw materials that are poly based such as polythene, polycarbonate, etc nylon can also be used. These materials have to be ground before they are used in the rotomoulding process.

Injection Molding 

It is a process that involves injecting heated plastic into a mold. It is ideal for creating small durable products, since the high pressure used gives the products high tolerance.

Advantages of Injection Molding 

Production is very fast. It makes it possible to produce many parts within a short time. It can take about 30 seconds to have a number of finished products, depending on the amount of mould that you have placed in your tool.

Cuts down on labor costs – The tool can be automated to function with minimal labor. With this added benefit it can cut down on production costs.

Complex products – The use of extremely high pressure to compress the heated plastic into a mold makes it possible to add complex features that would be shaped into the finished product.

Accuracy – The molds are custom made, which means that it is very possible to get the exact product you want. This also allows for flexibility in design as long as one stays within the restrictions that come with this process of manufacturing.

Choices – With injection molding, it is possible to use more than one type of plastic on one product, a process called co injection molding

Disadvantages

Costly – The machine can be very expensive especially for a small start up company.

Limited – The design options are a bit limited with this process.

To Rigid – The fact that the molds are created before the process begins tends to make it rigid, with no room for flexibility once the manufacturing process has begun.

More Expense – The making of a mold is also costly when compared to rotational molding.

Less Stability – The products tend to be weaker when compared to other processes

Blow Molding

It is a plastic manufacturing process where air is used to create hollow plastics by inflating soft plastic against a mold. It is ideal for creating bottles and other plastic containers.

Advantages

The tooling cost is more affordable when compared to injection molding.

Disadvantages

Limited – The manufacturing options are limited to small hollow products.

Less control – The process makes it hard to control the wall thickness of a product, stretching the material according to the amount of air blown into the mold.

No hole option – It is impossible to manufacture holes into a product. This can only be done after the molding process is finished.

Longer process – Products take a longer time to cool when compared to injection molding.

It is evident that each plastic molding type is good for specific products. For instance, blow molding has an advantage over rotomoulding when it comes to bottle manufacturing. Rotomoulding on the other hand is better for the making of strong tanks and other complex products. Injection molding has the capability to manufacture a lot of goods within a short time but is relatively expensive. Depending on the product needed, the cost of production is highly dependent on the type of  plastic molders used.