What is an Injection Molding Machine? Get to know everything about it! Plastic4trade
What is an Injection Molding Machine? Get to know everything about it!

17 May 2023

Injection molding is an important industrial technique. Although it is somewhat similar to die casting, but the raw material used in this case are different. Die casting uses metals that melt at extremely high temperatures, whereas injection molding mostly uses glasses, elastomers, and most frequently thermoplastic and thermosetting polymers. Nevertheless, this process is commonly used to create thermoplastic materials. In this method, raw materials are heated to a certain temperature and then injected under pressure into the mould cavity without changing their composition.


What are the main parts of injection molding machine?


The material hopper, barrel, an injection ram/rotating screw type plunger, heating element (heater), adjustable pattern, ejectors, and a mould inside mould cavity are the key components of an injection molding machine.


Injection molding machines typically operate horizontally. A barrel is part of an injection molding machine (cylindrical pipe). At one end of the barrel, there is a hopper. Inside the barrel is a revolving screw or hydraulic ram powered by an electric motor that provides force. The barrel has a heating element (warmer) attached to it that is used to melt the molding compound when it exits the hopper.


Mold cavity linked to the barrel's opposite side. During the entire production process, a movable pattern is used and the mould is situated inside the mould cavity. Typically, copper, aluminum, and tool steels are used to make mould. Distinct types of material moulds have different life cycles. This can be chosen based on your needs.


How does the injection moulding machine works?


Extrusion and injection molding both function similarly, as implied by their names. Using a feeding apparatus, molding material and raw materials are poured into the hopper. Following that, the molding material falls into the cylinder (barrel) as depicted in the diagram due to gravity. The material is melted using a circumferential heater that is mounted on the barrel. When molding compound in powder form enters the barrel from the hopper, it begins to melt, and a revolving screw or hydraulic ram applies pressure to advance the compound into the mould.


In this split mould, which is attached to the other side of the barrel, molten plastic material is pumped into a closed mould. The revolving screw constantly advances the molding material. The hydraulic system exerts pressure. Normal injection pressure ranges from 100 to 150 MPa. Following injection, pressure is exerted for a while or held in place with some force.


The pieces produced when the entire procedure is complete are appropriately cooled. The mould is then opened, and a few ejectors are utilized to remove the part properly and damage-free. The portion mould is reopened after removal. This process is very fast and automatically repeated. Here, it is simple to make pieces with complex shapes. The injection molding process may produce 12–16,000 components every cycle.


The Procedure


-    The process parameter fluctuates based on the circumstances and demands.
-    The components made with this method typically weigh between 100 and 500 g.
-    A single part's cycle time ranges from 5 to 60 seconds, depending on how the item is made.
-    The heating range for molding material is 150 to 350 degrees Celsius.
-    The molding machine has an injection capacity of 12,000 to 2.2 106 mm3.
-    100 to 150 MPa is the injection pressure.
-    From 0.1 to 8.0 MN is the locking force.


What are the advantages of Injection molding machine?


-    The fundamental benefit of this method is that intricately shaped components with thin walls (5–15 mm) may be molded with ease and retrieved from the die without being harmed.
-    Injection-molded components offer good dimensional tolerance.
-    The main benefit of this method is that it produces far less scrap than certain other methods.
-    Investment cast iron and intricately machined pieces compete with parts produced through the Injection Moulding Method.
-    In comparison to other procedures, this process has a high production rate.


What are the various types of injection molding machines?

Following are the different types of injection molding machines. Have a look:


Hydraulic Injection Molding Machine

Hydraulic injection molding machine were the only types of machine at start. It is the oldest one in the industry. Following are the benefits of this machine-


1. Economical price
These machines cost far less at the base level than comparable models.


2. Cheap parts
If a machine component needs to be replaced because it has been damaged or has reached the end of its useful life, the replacement parts are less expensive and more readily available.


3. Robust components
The machine's hydraulic components are longer-lasting and more resistant to deterioration.


4. Easy to use and maintain
High-pressure clamping forces are typically simple to adjust on hydraulic injection devices.


5. Powerful
The gripping force on hydraulic molding machines is outstanding.


Electric Injection Molding Machines

In the 1980s, electric injection molding machines were made available and soon gained popularity in the high precision plastic parts production sector. The positioning accuracy of today's full electric servo drive injection molding machines is exceptionally precise (of 0.0001 in), but at a very high cost.


1. Less idle time
There is no possibility of oil leaking. Additionally, since no oil is used, there is no need to replace filters, which lowers consumable costs.


2. Efficiency while using energy
Electric Injection Molding Machines only consume energy when they are in use, thus their output is limited to what is necessary to support the load.


3. Fast procedure
Since these machines are digitally controlled, the procedure can be completely repeated without any oversight.


4. Highly reproducible
The injection device can be accurately controlled, the molding conditions can be stabilized, the injection control (such as pressure and speed) can be regulated in fine units, and there is a highly accurate control and monitoring system. It can handle challenging tasks like multi-stage hydraulic system extension and control the extension.


Injection Molding Machine Price


There are various types of machines. The Injection Molding Machine Price will also vary according to the complexity of the machine. 
Costs for large industrial injection molding equipment can range from $50,000 to $200,000 or more. Additionally, the facilities needed to operate, maintain, and monitor these equipment are more demanding and call for expert staff.


Who are the best injection molding machine manufacturers?


There are many Injection Molding Machine Manufacturers in India; however, some of them offer the exception quality products that last longer. Here is the list of some trusted manufacturer in India-

  • Milacron

  • Yizumi Injection Molding Machine

  • Primex Plastics Pvt. Ltd

  • Windsor Machines Limited

  • Haitian

  • Hikon

  • ENGEL Global

  • Indo-MIM

  • Micro Plastic

  • Kruger

  • Vikas Industries

  • Jagmohan PlaMech Pvt. Ltd

  • Neelgiri Machinery

These are some of the leading manufacturers offering the best quality Injection Molding Products. If you are looking for someone in your region, you can try to search on Google and write Injection Molding Machine near me. This way, you will find the list of top-rated manufacturers offering top-notch services in your area.


Types of products made with injection molding machine


There are various types of products that can be made with injection molding machines.

Some of them are listed below-

  • Toys

  • Plastic bottles

  • Machinery and automotive components

  • Household products like molded closures, containers, etc.

  • Healthcare industry

  • Agricultural products


Injection moulding may appear to be a complicated procedure, yet it is the most popular manufacturing technique because it can manufacture a wide range of everyday things quickly and effectively. One of the most economical methods for producing both working prototypes and finished goods is injection molding.