Lost Foam Casting

Explore the efficiency of Lost Foam Casting (LFC), a transformative foundry method where metal is seamlessly poured into an expanded polystyrene foam pattern, facilitating the creation of complex, finely detailed castings. Noted for their high precision, dimensional accuracy, and superior surface finish, these castings set a new standard in the industry.

In castings without cores, the cost-savings are 20% and as compared to the conventional castings with cores, cost-savings in LFC are more than 30%.

At GDM TECHNICS, we specialize in providing comprehensive project consulting for setting up Lost Foam Casting foundries.

Our turnkey solutions are tailored to meet the unique needs of each client, their products and future product plan, ensuring a seamless transition to this advanced casting technology.

Lost Foam Casting Process by GDM Technics:

1. Creating Precise Foam Patterns & Gating Systems
   • In this innovative casting technique, foam patterns are fabricated or die-moulded to replicate the final metal product’s exact shape. The gating system, essential for directing the molten metal, can be either integral or attached to these patterns. This results in precise and efficient casting.
   • Combining foam patterns with gating systems forms a crucial mould tree module. This step is pivotal for aligning components accurately, minimizing errors, and ensuring consistent production of complex metal parts.
2. Applying & Drying Refractory Coating
   • The assembled module receives a coat of refractory by dipping, flooding or flow-coating to a certain Baume degree. Once dried, this forms a sturdy tree, enhancing the mould’s resilience against heat and pressure during the casting.
3. Setting the coated foam pattern in the flask
   • The coated tree is then placed in a moulding flask, enveloped by dry sand. This stage is critical for maintaining the mould’s shape, ensuring stability during casting, and achieving uniform sand compaction.
   • Vibrating the moulding flask allows the sand to fill every part of the mould, ensuring detailed and accurate casting through effective compaction.
   • Activating the vacuum assistance in the sandbox enables the desired mould hardness. Vacuum also ensures the evacuation of foam and metal fumes.
4. Molten Metal Pouring & Foam Vaporization
   • Molten metal is poured into the mould, evaporating the foam pattern. This step guarantees that the metal precisely forms the desired casting, maintaining the shape while reducing imperfections, and accommodating complex designs.
5. Knock-Out Phase
   • The sandbox is turned over. The free-flowing sand flows to the sand cooler and casting is retrieved.

The recyclability of the used dry sand contributes to cost-savings and energy conservation.

Lost foam casting distinguishes itself from traditional methods like sand casting or investment casting through its unique capabilities. This method excels in fabricating complex and detailed designs that might be challenging with other techniques.

LFC caters to a range of products from simple to highly complex. It is compatible with various metals, including steel, ductile iron, grey iron, aluminium, magnesium, and brass.

What are Lost Foam Casting Benefits?

• LFC produces castings with high dimensional accuracy (±0.005mm/mm) and state surface finish between 2.5 and 25 µm.
• Eliminating the draft requirement and parting lines, hence no flash or fins, and no machining is needed post-casting.
• LFC leverages the low boiling point of foam made of Expanded Polystyrene or STMMA-FD, streamlining the process of casting, and making it more economical as compared to conventional methods.
• LFC can perform highly intricate and detailed castings.
• No rejections due to core shifting; and if there is no core, no core cost.
• Sand can be re-used since no binder is used in LFC, almost zero wastage.
• LFC is metallurgically efficient and has fewer steps, hence lower costs.
• Lost Foam Casting is a versatile foundry process that can cast from 0.5 Kg to several tons.
• Minimum wall thicknesses are just 2.5mm with no upper limit.
• Another significant benefit of Lost Foam Casting is the reduced need for risers. The process inherently allows for natural directional solidification because the molten metal vaporizes the foam, then fills and cools in the mould, ensuring quality and consistency in the final product.
• Most economical, sustainable, and eco-friendly, and clean moulding process.
• Satisfied customers, greater reputation of foundries, and hence more orders!

Fabricating or Die-Moulding the Lost Foam Pattern

The creation of a foam pattern in lost foam casting is a finely tuned process, heavily influenced by the design and intricacy of the product. The initial step involves utilizing an EPS (Expanded Polystyrene)/ STMMA-FD moulding machine, a cornerstone in the lost foam casting process.

The intrinsic properties of foam make it an ideal material for LFC. It’s notably easy to shape, carve, and adhere.

The precision of shaping foam is enhanced with the use of a CNC hot wire foam cutter, further elevating the process’s efficiency and accuracy.

This adaptability of foam is a crucial advantage in LFC, often permitting the fusion of multiple components into a single, unified part through CNC glueing.

Lost Foam Casting in India

Lost Foam Casting is revolutionizing India’s foundry sector with its cost-effectiveness and superior quality. Indian foundries are swiftly adopting LFC, driven by its ability to modernize operations, elevate profitability, and significantly grow order volumes.

GDM TECHNICS leads this change, pioneering Lost Foam Casting in India. Renowned for our project consulting expertise, we cater to key foundry hubs such as Bhilai, Raipur, Vadodara, Rajkot, Ludhiana, Kolhapur, and Belgaum.

Our expertise extends to delivering LFC turnkey projects across various industries, including steel and sinter plants, pellet plants, coke ovens, railway coach factories, and the automotive sector. We also cater to the needs of pump casings, valve bodies, motor bodies, bi-metallic crusher parts in foundries, and the mass manufacturing industry.