Premium Cosmetic Packaging Box – Injection Molding Manufacturing Case Study

I. Product Shape and Description

1. Product Shape: See the image below.

2. Product Description:

Outer Diameter: 60mm; Height: 40mm;

Product Weight: 100g;

Maximum Wall Thickness: 15mm;

Number of Outlets: 1 outlet + 2 inlet;

Feeding Method: Hot Runner Material: PCTA

II. Problems and Solutions in Injection Molding Production

1. Cold Glue

The solution is to select a good hot runner, reasonable back pressure, allowance, and hot runner temperature.

2. Flow Marks and Air Blows

The solution is to control the injection speed; it should be slow but not too slow, otherwise defects such as "cow dung" marks, ripples, and dullness will appear.

3. Shrinkage and Vacuum Bubbles

The solution is to adjust parameters such as holding time, holding pressure, and mold temperature.

4. Final Process Adjustment

A. Barrel Temperature: The temperatures of the front and rear barrels (5 short intervals from front to back): 245, 250, 240, 200, 180 degrees Celsius.

B. Injection Parameters:

Injection 1: 1200kg pressure, 6% speed, 5% glue feed;

Injection 2: 1200kg pressure, 3% speed, 5% glue feed;

Injection 3: 900kg pressure, 20% speed, 70% glue feed;

Injection 4: 700kg pressure, 15% speed, 10% glue feed;

The actual total injection time is approximately 10 seconds.

C. Holding Pressure Parameters: Roughly 800kg pressure, holding pressure for 25 seconds.

D. Other Parameters: Back pressure 5kg. Cooling time is normally over 100 seconds, but due to the use of advanced processes, the time is reduced to 40 seconds, with the final cycle time approximately within 90 seconds.