Counterweights Integrating Plastic Film Vacuum Process Production Line Cast iron

Vacuum-process casting, also known as vacuum-sealed molding, is an advanced casting technology based on physical molding and negative-pressure fixation. It fundamentally differs from traditional sand casting by eliminating the use of binders and moisture. Instead, it relies on plastic film sealing, dry quartz sand filling, and vacuum negative pressure to stabilize the mold, producing castings with smooth surfaces, high dimensional accuracy, and dense internal structures.

In simple terms, the core process flow is as follows:

1. Film Heating and Forming System

   The EVA film is automatically cut, stretched, and heated so that it perfectly adheres to the mold surface. This is the first critical step in achieving a smooth and high-quality casting surface.

2. Sand Flasks and Traveling Vibration Compaction Table

   Specialized sand flasks are equipped with high-efficiency pneumatic vibration tables, ensuring that dry sand is uniformly and densely compacted into every corner of the mold under negative pressure.

3. Vacuum System (The Heart of the Production Line)

   This is the core component of the line. We provide stable, efficient, and energy-saving vacuum pump units combined with an intelligent control system to maintain a constant and adjustable negative pressure throughout molding, pouring, and cooling. This is essential for preserving mold strength.

4. Flask Turning and Mold Closing System

   Using precision guiding mechanisms and power drives, this system enables smooth flask turning and accurate mold closing, ensuring precise alignment between upper and lower flasks and reducing mismatch defects.

5. Rainfall-Type Sand Filling System

   By simulating a “rainfall" effect, dry sand is filled into the flask evenly and gently, avoiding impact on the film and mold while preventing uneven sand compaction.

6. Sand Drop and Sand Reclamation System

   After pouring and cooling, the vacuum is released, allowing the casting to automatically separate from the sand mold. The dry sand is then cooled, dedusted, and screened, achieving nearly 100% recycling, significantly reducing material costs and environmental burden.

7. Intelligent Control System

   A PLC / industrial PC centralized control system with an integrated Human–Machine Interface (HMI) is adopted. It enables real-time monitoring of all key parameters—such as vacuum level, vibration time, film heating temperature, and production takt—while supporting one-touch start/stop, fault diagnosis, data traceability, and report generation, laying a solid foundation for a smart factory.

1. Ultra-High Casting Quality

   Excellent surface finish: Casting surface roughness can reach Ra 12.5–25 μm, approaching the level of investment casting, greatly reducing cleaning and machining time.

   High dimensional accuracy: By eliminating expansion and deformation caused by moisture and binders, the process ensures excellent dimensional stability.

   Fewer internal defects: Outstanding sand mold permeability effectively reduces defects such as porosity, sand inclusions, and slag entrapment.

2. Significant Cost Savings

   Low material cost: Sand requires no binders or water, with a recycling rate of over 97%, resulting in minimal sand consumption.

   Lower energy and labor costs: A simplified process eliminates sand mixing and mold drying, is easy to automate, and can reduce labor requirements by 30–50%.

   Lower environmental compliance costs: No harmful gas emissions and simple dust control significantly reduce environmental management investment.

3. Truly Green and Environmentally Friendly

   Pollution-free: No harmful fumes (such as formaldehyde or SO₂) generated from chemical binders like resins or sodium silicate.

   Low emissions: The working environment is greatly improved and fully complies with the most stringent environmental regulations, making it an ideal choice for sustainable development.

4. Outstanding Process Flexibility

   Wide choice of molds: Wooden, resin, and metal molds can be used. Mold costs are relatively low, and design modifications can be implemented quickly.

   Broad application range: Particularly suitable for medium and large-sized, thin-walled, and complex castings, such as machine tool beds, housings, pallets, pressure-resistant valve bodies, and artistic castings.

• Process support: From product manufacturability analysis to mold design guidance
• Turnkey projects: From site planning to installation, commissioning, and personnel training
• Lifetime service: Spare parts supply, remote diagnostics, and process optimization services to ensure long-term stable operation of the production line

Step into high-end casting—starting with one right choice.

Contact us today to obtain a customized V-process casting solution and a comprehensive economic benefit analysis report tailored to your products.