Choosing The Best Degassing Technology for Your Aluminum Die Casting Process

In aluminum die casting, molten metal quality is one of the most critical factors that determine the strength, durability, and surface finish of castings. One of the biggest challenges is hydrogen gas, which easily dissolves into molten aluminum. If not removed, it causes porosity, lower mechanical properties, and higher rejection rates.

To address this, foundries rely on degassing units. Two widely used technologies are Static Gas Bubbling (SGB) and Rotary Gas Bubbling (RGB). But which one is better for your process? Let’s break it down.

 

1. Static Gas Bubbling (SGB)

How it works:
SGB introduces inert gas (usually argon or nitrogen) through a static lance or bubbling pipes inserted into the molten aluminum.

✅ Advantages:

• Simple system, easy to install.
• Lower investment cost compared to rotary systems.
• Practical for small molten metal furnaces for aluminum.

⚠️ Limitations:

• Gas forms larger bubbles, leading to less effective hydrogen removal.
• Slower degassing process.
• Inconsistent performance for larger melting furnaces for HPDC.

2. Rotary Gas Bubbling (RGB)

How it works:
RGB uses a rotating shaft and impeller to disperse inert gas into the molten metal, creating fine and evenly distributed bubbles.

✅ Advantages:

• Superior hydrogen removal due to fine bubble distribution.
• Faster and more consistent degassing performance.
• Highly effective for aluminum die casting furnaces with larger capacity.
• Advanced ceramic-coated impellers provide longer service life.

⚠️ Limitations:

• Higher initial investment compared to SGB.
• Requires periodic maintenance of shaft and impeller.

3. Which Technology Should You Choose?

The choice between RGB and SGB depends on your furnace type, production capacity, and quality requirements:

• SGB: Best for small-scale operations, lower budget, and standard quality requirements.
• RGB: Ideal for high-quality aluminum die casting, large-scale production, and furnaces for HPDC where porosity control is critical.

Both Static Gas Bubbling (SGB) and Rotary Gas Bubbling (RGB) play important roles in removing hydrogen from molten aluminum. SGB is cost-effective and simple, while RGB delivers higher efficiency and consistency for demanding aluminum die casting processes.

At PT Wilisindomas Indahmakmur, we provide customized degassing solutions for every aluminum die casting furnace—helping manufacturers achieve the right balance between cost, efficiency, and product quality.

Contact us today to find the most effective degassing technology for your process.