Injection Moulding vs Vacuum Forming | Moldwel | Plastic Moulding

Injection Moulding and Vacuum Forming are the two most popular and commonly used processes in plastic manufacturing.

The aim of this Blog is to provide a brief overview of each method with the relative merits ( and drawbacks ) associated with each.

What is Vacuum Forming? 

Vacuum forming, sometimes also referred to as Thermoforming, is a process where plastic sheets are heated in automated forming equipment until soft and malleable, when it is then “formed” around a shape or mould. A vacuum source is then turned on to suck the plastic sheet to the mould shape. When the formed sheet has cooled sufficiently the excess sheet not used is trimmed off to give the final, finished component.

What is Injection Moulding? 

Injection Moulding is a far more complex, detailed process. The plastic used in this comes in a granule form which is then heated in a barrel until it becomes plasticised. This is then injected from the barrel into the mould tool. Once cooled the finish component, in its solid form is ejected from the tool.

 

Both processes have their own very distinct advantages and disadvantages.

Vac Forming

Advantages :

  1. Vacuum forming has shorter lead times on new tooling.
  2. Much lower tooling start up costs.
  3. This method has the ability to create larger plastic parts.
  4. Relatively low costs for smaller batch requirements.

 

Disadvantages :

  1. Consistency in wall thickness / uniformity of plastic products is not always achievable.
  2. Limited in the detail and complexity of parts.
  3. This method is not cost effective on larger batch runs.
  4. Additional time and cost involved in the finishing process.

Injection Moulding 

Advantages :

  1.  A wide variety of different materials, with different mechanical properties can be used.
  2. Parts can be made from any colour required.
  3. Inserts can be used within the moulding process.
  4. Closer tolerances and more intricacy within the design is possible.
  5. Far more cost effective on large run / repeat orders.
  6. Very little waste / scrap is produced – this can be reground and re-used.

 

Disadvantages :

  1. Higher initial start up costs because of the tooling needed.
  2. More skill, knowledge and experience is required.
  3. Initial tooling manufacture has a longer lead time.

 

Moldwel – We are leading plastic injection moulding suppliers based in the Midlands. Our team of expert technicians can help you with any project. Give us a call on 01922 631252 for free expert advice or visit our website for more information on plastic injection moulding.

If you enjoyed reading this article you may also like to see our previous post on our new injection moulding machine.