industrial level polymer shape production is conventional when we use injection molding. it will help you understand, how injection molding works and what may cause problems in it.

1. 1
Injection Molding:

2. mold cavity melt
nozzle
plastic pellets
hopper
screw
heating
coils
cold side hot side
parting line
plates
Injection Mold
Major
parts of
the
injection
molding
machine
barrel
2

3. Process
Plastic pellets fill the hopper…
…to form melt in the nozzle…
…fall into
the barrel…
…where
heat and
pressure
are
applied…
…which is pushed
into the mold.
3

4. Process
After cooling, the mold opens
and the finished part is removed.
The sprue is then removed
from the final part.
It is reground
and placed
back into the
hopper.
4

5. The diameter of the screw inside the barrel gradually increases to
generate more pressure and heat helping to melt the material.
5

6. Shape Complexity
Advantages
Quantity
Quality
Materials Available
Cost per Unit
6

7. Disadvantages
Complex geometry can render parts
impossible or extremely expensive.
Unless mass producing, the cost of the mold can
outweigh the benefits of injection molding.
7

8. Materials
Thermosets: Thermal Insulator
High Strength and Hardness
Nonreversible
Thermoplastics: Low Cost
Manufacturability
Reversibility
8
Two main types of plastics: