Technical Parameters:

Product Description:

The Double Stage Vacuum Extruder is the most crucial forming equipment on modern brick and tile (fired bricks, hollow bricks, blocks, etc.) production lines. It continuously extrudes prepared plastic clay into dense, uniform clay strips with certain strength and shape through a two-stage process (primary mixing/kneading and secondary vacuum extrusion), laying the foundation for subsequent cutting, drying, and firing.

"Double Stage" refers to the equipment consisting of two parts: the upper stage and the lower stage. "Vacuum" means that the clay is de-aired by vacuum treatment before extrusion in the lower stage.

Core Working Principle:

Its operation follows the process of "Pre-treatment → Vacuum De-aeration → High-pressure Extrusion":

1.Upper Stage - Mixing and Sealed Feeding:

Prepared clay is fed via conveyor into the upper stage mixing chamber.

The mixing shaft (typically equipped with paddle blades) further mixes, kneads, and conveys the clay, making its moisture and particle distribution more uniform and improving plasticity.

The end of the upper stage forces the clay into a sealed clay chamber, creating a seal for the lower stage vacuum chamber.

2.Vacuum Treatment - De-aeration and De-bubbling:

The clay enters the vacuum chamber of the lower stage.

The vacuum pump operates continuously to evacuate air from the vacuum chamber, achieving a high level of vacuum inside

Under negative pressure, air trapped within the clay expands rapidly and is removed. This process is vital for effectively eliminating bubbles and voids in the clay.

3.Lower Stage - High-pressure Extrusion and Forming:

The de-aired clay enters the lower stage extrusion screw (auger) area.

Driven by the screw with varying diameter and pitch, the clay is continuously compressed and conveyed, with pressure increasing sharply.

The high-density, bubble-free clay is finally extruded through the die mouth (mold), forming a continuous clay strip with the designed cross-sectional shape (solid, perforated, hollow, etc.).

Core Advantages and Features:

1.Improves Product Quality:

High Density: High-pressure extrusion results in denser green bodies, leading to higher fired strength.

Eliminates Defects: Thorough vacuum de-aeration removes internal laminations, cracks, bubbles, etc., significantly reducing waste.

Precise Shape: Extruded clay strips have accurate dimensions and clean edges.

2.Enhances Production Efficiency:

Continuous Operation: High automation enables stable output.

Strong Adaptability: Handles fluctuations in raw materials (shale, coal gangue, sludge, clay, etc.) relatively well.

3.Saves Energy & Reduces Consumption:

High-quality green bodies may allow shorter drying and firing cycles, reducing fuel consumption.

De-aired bodies have higher initial strength, reducing breakage during handling and setting.

4.Operational Flexibility:

Can produce bricks and blocks of different specifications and hole patterns by changing the die mouth (mold).

Upper stage mixing intensity and lower stage extrusion speed can be adjusted to suit clays with different plasticity.

Summary:

The Double Stage Vacuum Extruder is the cornerstone for modern brick plants to achieve high-quality, high-efficiency, and automated production. Its integrated "kneading-vacuum-high pressure" process fundamentally solves the inherent quality issues of traditional green bricks. Investing in a well-performing, reliable Double Stage Vacuum Extruder is a crucial decision for brick plants to enhance product competitiveness, lower overall production costs, and achieve sustainable development.