Comprehensive Analysis of Aluminum Cup Manufacturing — Core Processes Chapter

Every cup holds a story, and life is filled with warmth. Hello everyone, and welcome to "Dong Dong's Cup Talk" Many friends already know that I primarily specialize in producing various types of stainless steel cups and plastic cups. Although I previously shared an in-depth analysis of glass cups, https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmlit was made possible with the help of friends. If you encounter any issues when purchasing or developing stainless steel or plastic cup products, feel free to message me privately. I am more than happy to provide you with dedicated assistance.

Perhaps due to the season or the arrival of another peak sales period, I have recently received numerous inquiries from around the world about purchasing aluminum cups. This inspired me to share some insights about aluminum cups. https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmlConsidering my limited expertise in this area, I have invited Mr. Xuan, who has nearly 20 years of experience in operating an aluminum cup factory, to elaborate on the intricacies of aluminum cup manufacturing.

Detailed Explanation of Core Production Processes for Aluminum Cups (Using Deep Drawing as an Example)

1. Uncoiling and Blanking of Aluminum Coil

- Aluminum coil (3104/H24 state alloy, thickness 0.8-1.2mm) is selected, leveled, and punched into circular blank discs.

- Expert Tip: The blank diameter must be precisely calculated. Excess size wastes material and increases drawing resistance, https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmlwhile insufficient size may lead to inadequate cup height or cracking.

2. Deep Drawing Forming (Key Process Analysis)

- Process: The blank disc is pressed by a hydraulic machine, where the punch forces it into the die, forming the basic cup shape in a single stroke.

- Technical Challenges and Solutions:

- Wrinkling: Caused by instability at the flange edge under pressure.

Solution: Precisely control blank holder force (dynamically adjusted during the process), polish the die entry radius to a mirror finishhttps://www.zhanyict.com/en/ProductsDetail-VB-10098.html (Ra ≤ 0.2μm), and apply high-viscosity drawing oil (e.g., chlorine-based additives).

- Cracking: Stress concentration at the bottom corner.

Solution: Increase the punch head radius (at least 3 times the material thickness), polish the die corner to eliminate seams, and design micro vent holes (φ0.3mm) at the die corner to prevent air cushion effects that cause suspended stretching and cracking.

- Uneven Wall Thickness: Caused by uneven punch speed.

Solution: Use servo hydraulic machines with variable speed curves: https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmlslow initial contact → medium-speed forming → fast demolding.

3. Trimming and Cleaning

- Laser precision trimming removes excess flange edges.

- Alkaline degreaser (60°C) thoroughly eliminates drawing oil and oxides.

4. Internal Coating (Core Technology)

- Electrostatic spraying is used to uniformly coat the inner wall with food-grade epoxy resin (film thickness 15-20μm), https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmlcured at 280°C to form a dense protective layer.

- Expert Tip: Ensure the cup is completely dry before coating to prevent pinholes in the coating.

5. External Surface Treatment

- Anodizing (High-End Mainstream Method):

- Conducted in a sulfuric acid electrolyte to generate a dense Al₂O₃ oxide film (12-15μm thick).

- Can be dyed in various colors, https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmloffers high hardness (HV300+), and is wear-resistant.

- Painting/Powder Coating:

- Suitable for complex patterns.

- Solution for Peeling Issues: The base material must undergo chromating or phosphating to enhance adhesion. Use weather-resistant polyester powder (cured at 200°C) with a film thickness of 60-80μm.

6. Spinning and Curling

- CNC spinning machines are used to gather and curl the cup mouth, https://www.zhanyict.com/en/ProductsDetail-VB-10098.htmlforming a smooth and thick lip.