Types of Plastic Mould & Their Design, and Uses
Types of Plastic Mould & Their Design, and Uses
Plastic moulds are used in various industries to manufacture plastic components with precision and efficiency. Different moulding techniques are used based on the product design, material, and production requirements.
Injection Moulding : Click Here
Process:
- Molten plastic is injected into a mould cavity at high pressure.
- The plastic cools and solidifies into the desired shape.
- The mould then opens, and the finished part is ejected.
Design Features:
- Mould consists of a core and cavity.
- Includes cooling channels for uniform solidification.
- Uses ejector pins for part removal.
Main Parts:
- Hopper – Holds raw plastic pellets before melting.
- Barrel & Heater – Melts the plastic using heat and pressure.
- Screw & Reciprocating Plunger – Moves and injects molten plastic into the mould.
- Mould (Core & Cavity) – Shapes the plastic into the final product.
- Cooling Channels – Circulates coolant to cool and solidify the part.
- Ejector System – Pushes out the finished product from the mould.
- Clamping Unit – Holds the mould in place during injection.
Example: Car dashboards, plastic chairs, electronic casings
Uses: Mass production of automotive parts, medical devices, electronics, toys, and consumer goods.
Blow Moulding : Click Here
Process:
- A heated plastic tube (parison) is placed inside a mould.
- Air is blown inside, expanding the plastic to the mould’s shape.
- The plastic cools and solidifies, forming a hollow object.
Design Features:
- Mould has a cavity to shape the plastic.
- Uses air pressure for shaping.
- Cooling system integrated for quick solidification.
Main Parts:
- Extruder – Melts and forms plastic into a hollow tube (parison).
- Blow Pin/Nozzle – Injects air to expand plastic inside the mould.
- Mould Cavity – Shapes the outer structure of the plastic.
- Cooling System – Ensures quick solidification.
- Trimming System – Cuts off excess plastic after forming.
Example: Plastic bottles, fuel tanks, and containers.
Uses: Production of plastic bottles, containers, fuel tanks, and packaging materials.
Compression Moulding : Click Here
Process:
- A preheated plastic material is placed in a mould cavity.
- The mould is closed, applying heat and pressure to shape the material.
- The material solidifies into the final shape.
Design Features:
- Upper and lower mould plates apply pressure.
- Heating elements ensure even curing.
- Suitable for thermosetting plastics.
Main Parts:
- Upper (Top) Mould Plate – Applies heat and pressure to form the shape.
- Lower (Bottom) Mould Plate – Supports the plastic material.
- Heating System – Ensures even temperature for shaping.
- Hydraulic Press – Applies pressure to shape the plastic.
- Cooling System – Solidifies the final part.
Example: Electrical switchgear, automotive parts, rubber gaskets.
Uses: Used for making automotive parts, electrical switches, and heavy-duty components.
Extrusion Moulding : Click Here
Process:
- Plastic material is melted and forced through a shaped die
- The extruded plastic cools and hardens into a continuous shape.
Design Features:
- Includes a screw mechanism to push melted plastic.
- Die shapes the plastic as it exits.
- Cooling system ensures shape retention.
Main Parts:
- Hopper – Holds raw plastic material before melting.
- Extruder Screw & Barrel – Moves and melts plastic using heat and pressure.
- Die – Shapes the plastic into a continuous profile.
- Cooling System – Uses air or water to cool and harden the extruded plastic.
- Cutting System – Cuts the extruded plastic into desired lengths.
Example: Pipes, plastic straws, window frames.
Uses: Production of pipes, tubing, plastic sheets, and window frames.
Rotational Moulding (Rotomoulding) : Click Here
Process:
- Plastic powder is placed inside a rotating mould.
- The mould is heated, melting the plastic and coating the inner surface.
- The mould cools, solidifying the plastic into a hollow part.
Design Features:
- Mould rotates along two axes.
- No seams or joints in the final product.
- Mould is made of metal for even heat distribution.
Main Parts:
- Mould – A hollow metal structure that shapes the plastic.
- Heating Chamber – Rotates the mould while heating plastic powder.
- Rotation System – Moves the mould in multiple directions for even distribution.
- Cooling System – Helps the plastic solidify inside the mould.
- Demoulding System – Releases the final product from the mould.
Example: Water tanks, kayaks, playground equipment.
Uses: Large hollow tanks, playground equipment, kayaks, and traffic cones.
Thermoforming : Click Here
Process:
- A plastic sheet is heated until flexible.
- The sheet is placed over a mould and shaped using vacuum or pressure.
- Excess material is trimmed off.
Design Features:
- Uses a single-sided mould.
- Vacuum or pressure ensures shape formation.
- Simple and cost-effective for thin plastics.
Main Parts:
- Heating Element – Warms the plastic sheet to make it flexible.
- Mould – Forms the plastic into the required shape.
- Vacuum System (or Pressure System) – Pulls or pushes plastic onto the mould.
- Trimming System – Cuts excess plastic after shaping.
- Cooling System – Solidifies the shaped plastic.
Example: Disposable cups, food packaging trays.
Uses: Used for packaging trays, disposable cups, and food containers.
Transfer Moulding : Click Here
Process:
- Heated plastic is placed in a chamber and forced into a closed mould using pressure.
- The material solidifies inside the mould cavity.
Design Features:
- Requires high-pressure injection.
- Uses pre-measured plastic for minimal waste.
- Can mould complex shapes with high precision.
Main Parts:
- Transfer Pot – Holds preheated plastic material.
- Plunger/Ram – Pushes molten plastic into the mould cavity.
- Mould Cavity & Core – Shapes the final product.
- Heating System – Ensures uniform plastic flow.
- Ejector System – Removes the solidified product from the mould.
Example: Electrical insulators, circuit breaker casings.
Uses: Used for electrical components, circuit breakers, and industrial parts.