Find HS Code and trade information for foundry adhesive

Foundry Adhesive

Foundry adhesives are specialized bonding agents designed for use in foundry applications, primarily for securing sand molds and cores during the metal casting process. They are crucial for maintaining mold integrity and achieving accurate castings.

Material Composition

Foundry adhesives are broadly categorized based on their binder systems:

• Sodium Silicate-Based: These are the most common type, utilizing water glass (sodium silicate) as the primary binder. They react with CO₂ to form a silica gel that binds the sand particles. Variations include those modified with phenolic resins for improved strength and heat resistance.
• Phenolic Resins: These offer higher strength and better resistance to high temperatures and chemical attack compared to sodium silicates. They are often used in more demanding applications.
• Furan Resins: These are thermosetting polymers that provide excellent strength, dimensional stability, and resistance to hot metal erosion. They require a catalyst for curing.
• Urea-Formaldehyde Resins: Less common now due to environmental concerns related to formaldehyde emissions, but still used in some applications where cost is a primary factor.
• Water-Based Adhesives: Newer formulations utilizing acrylic or other polymer emulsions to reduce environmental impact and improve handling characteristics.

Purpose and Function

The primary functions of foundry adhesives are:

• Bonding Sand Grains: To create cohesive molds and cores capable of withstanding the stresses of pouring molten metal.
• Core-to-Core Bonding: To join core pieces together, forming complex internal geometries.
• Mold-to-Core Bonding: To secure cores within the mold cavity, preventing movement during metal pouring.
• Surface Coating: Some adhesives are used as coatings to improve mold surface finish and reduce metal penetration.
• Refractory Bonding: To bind refractory materials in the production of cores and molds for high-temperature applications.

Usage Scenarios

Foundry adhesives are employed in a wide range of casting processes:

• Sand Casting: The most common application, utilizing green sand, dry sand, or chemically bonded sand molds.
• Shell Molding: Bonding sand grains with phenolic resins to create thin, strong shells.
• Investment Casting (Lost Wax Casting): Adhesives may be used in the assembly of wax patterns or ceramic shells.
• Lost Foam Casting: Adhesives can be used to bond foam patterns together.
• High-Temperature Casting: Utilizing refractory adhesives for molds and cores exposed to extreme heat.

Common Types & Applications

• Sodium Silicate Adhesive (Water Glass): General-purpose bonding for green sand molds and cores. Economical and widely used.
• Phenolic Resin Adhesive: High-strength bonding for shell molds, cores requiring high temperature resistance, and complex geometries.
• Furan Resin Adhesive: Used in cores requiring exceptional strength and dimensional stability, particularly in automotive and aerospace applications.
• Core Paste: A highly concentrated adhesive used for bonding core pieces and sealing joints. Typically sodium silicate based.
• Refractory Cement: Used to bond refractory materials for high-temperature applications, often containing sodium silicate or phosphate binders.
• Paintable Refractory Adhesive: Designed for coating molds and cores, providing a smooth surface and preventing metal penetration.

Foundry adhesive is not explicitly defined within the provided reference material. However, based on potential material composition and application, the following HS codes may be relevant:

• 3926904000: This code covers “Other articles of plastics and articles of other materials of headings 3901 to 3914: Other: Imitation gemstones”. While seemingly unrelated, certain adhesives may utilize plastic components and fall under this broad category if not specifically classified elsewhere. The total tax rate is 32.8% (Base tariff: 2.8%, Additional tariff: 0.0%, Tariff after April 2, 2025: 30.0%).
• 3901909000: This code covers “Polymers of ethylene, in primary forms: Other: Other: Other”. If the foundry adhesive is based on ethylene polymers, this code could apply. The total tax rate is 61.5% (Base tariff: 6.5%, Additional tariff: 25.0%, Tariff after April 2, 2025: 30.0%).
• 3901905501: This code covers “Polymers of ethylene, in primary forms: Other: Other: Ethylene copolymers”. If the adhesive is an ethylene copolymer, this code is applicable. The total tax rate is 61.5% (Base tariff: 6.5%, Additional tariff: 25.0%, Tariff after April 2, 2025: 30.0%).
• 6815910011: This code covers “Articles of stone or of other mineral substances (including carbon fibers, articles of carbon fibers and articles of peat), not elsewhere specified or included: Other articles: Containing magnesite, magnesia in the form of periclase, dolomite including in the form of dolime, or chromite Containing by weight more than 70 percent magnesia, expressed as MgO, with carbon content ranging from trace amounts to less than 30 percent, and chemically bonded by resin or pitch”. If the adhesive contains a significant proportion of magnesia and is bonded with resin or pitch, this code may be relevant. The total tax rate is 55.0% (Base tariff: 0.0%, Additional tariff: 25.0%, Tariff after April 2, 2025: 30.0%).
• 6815994110: This code covers “Articles of stone or of other mineral substances (including carbon fibers, articles of carbon fibers and articles of peat), not elsewhere specified or included: Other articles: Other: Other Containing by weight more than 70 percent magnesia, expressed as MgO, with carbon content ranging from trace amounts to less than 30 percent, and chemically bonded by resin or pitch”. Similar to the previous code, this applies if the adhesive contains a significant proportion of magnesia and is bonded with resin or pitch. The total tax rate is 55.0% (Base tariff: 0.0%, Additional tariff: 25.0%, Tariff after April 2, 2025: 30.0%).

According to the provided reference material, the HS code options related to 'foundry adhesive' are limited, with only the following 5 found. It is crucial to determine the precise material composition of the adhesive to ensure accurate classification.