1. Design the Lighting Housing Mold
CAD Design: Create a detailed computer-aided design (CAD) of the LED street light housing, specifying features like heat sinks, mounting points, and openings for wiring.
Mold Design: Based on the CAD model, design the die casting mold. The mold is usually made of steel and has two halves: a stationary half and a movable half. It should incorporate features like cooling channels to manage temperature during casting.
2. Select the MaterialAluminum Alloy:
Aluminum is the most common material for LED street lighting housings due to its lightweight, strength, and excellent thermal conductivity. Alloys like ADC12 or A380 are frequently used.
Zinc Alloy: Sometimes zinc is used for smaller components, though aluminum is more common for larger housings.
3. Prepare the Die Casting Machine
Machine Setup: Die casting machines come in hot chamber or cold chamber types. For aluminum, cold chamber die casting is typically used because aluminum requires higher melting temperatures.
Temperature Control: The machine heats the aluminum alloy to a molten state (around 660°C for aluminum). The mold is pre-heated to prevent temperature shock, which could lead to defects like warping or cracks.
4. Injection of Molten Metal
Metal Injection: Molten aluminum is injected into the mold cavity under high pressure (usually between 1500 to 2500 psi). The high pressure ensures that the metal fills even the smallest features of the mold.
Cooling: Once the mold is filled, the part is cooled rapidly inside the mold. The cooling time varies depending on the thickness of the housing, but typically ranges from 10 to 30 seconds.
5. Ejection of the Casting
After the metal solidifies, the mold is opened, and the newly formed LED street lighting housing is ejected using ejector pins built into the mold.
The part may still be very hot, so care is taken to handle it properly.
6. Trimming and Deburring
Trimming: Excess material or “flash” around the edges of the casting is removed using trimming dies, machines, or manually.
Deburring: Sharp edges or burrs that result from the casting process are smoothed out using deburring tools or abrasive machines.
7. Surface Finishing
Shot Blasting: The casting may undergo shot blasting to remove any remaining imperfections and give the surface a uniform appearance.
Surface Coating: To protect the housing from corrosion and enhance its appearance, various surface treatments can be applied. Common methods include:
Powder Coating: A durable coating that provides weather resistance.
Anodizing: For aluminum housings, anodizing improves corrosion resistance and surface hardness.
Painting: In some cases, paint is applied for aesthetic purposes or extra protection.
8. Quality Inspection
Dimensional Check: Measure the part to ensure it meets design specifications.
Surface Check: Look for surface defects such as porosity, cracks, or rough finishes.
Fit and Functionality: Ensure that mounting points, cable entry ports, and heat sinks are in the correct positions and function as intended.
Advantages of Die Casting for LED Housing:
Precision: Die casting allows for the creation of intricate designs with tight tolerances.
Strength and Durability: Aluminum alloys used in die casting provide excellent structural integrity and long-lasting performance.
Thermal Management: Die cast housings can be designed with integrated heat sinks to manage the heat generated by the LEDs.
Mass Production: Die casting is highly efficient for mass production, allowing for consistent and repeatable results.
By following these steps, manufacturers can produce high-quality, durable, and efficient LED street lighting housings that provide effective thermal management and protection for the lighting components.
