 |
| Quantity: | |
|---|---|
Customized
NHD
▍What is a graphite boat for metallurgical casting?
A graphite boat for metallurgical casting is a carbon container used in high-temperature environments to hold, contain, and protect molten metal, serving the dual functions of a melting crucible and a molding die. Unlike small laboratory crucibles, industrial-grade graphite boats must meet the following requirements:
High-capacity holding — Capable of melting tens of kilograms to several tons of metal in a single batch, the boat must possess high compressive strength and structural stability
Repeated thermal cycling — Metallurgical furnaces undergo multiple daily cycles of startup, melting, pouring, and cooling; graphite boats must withstand thermal shock without cracking
Multi-metal compatibility — From ferrous metals (steel, iron) to non-ferrous metals (copper, aluminum, gold, silver) and rare earth metals, each with varying chemical inertness requirements
Long service life and cost-effectiveness — Industrial applications require graphite boats to maintain dimensional accuracy after hundreds of cycles, thereby reducing overall operating costs
Ningheda Carbon addresses the demanding conditions of metallurgical casting by offering material grading options (standard compression-molded grade, high-density isostatic grade, ultra-high-purity grade), structural reinforcement designs (ribs, buffer grooves, lifting structures), and optimized surface treatments (anti-oxidation impregnation, anti-adhesion coatings). This ensures that our graphite boats deliver the best value for money in your smelting environment.
High Purity Graphite Melting Boat
Custom Size Graphite
Sintering Boat Set
Rectangular Graphite Crucible Boat
▍Product Specifications
Performance Specifications | Standard Molding Grade | Isostatic Pressing, Premium Grade | Ultra-high purity grade |
Bulk density | 1.70-1.80 g/cm³ | 1.85-1.90 g/cm³ | 1.82-1.88 g/cm³ |
Grain size | ≤0.8mm | ≤25 μm | ≤25 μm |
Ash content | ≤0.3% | ≤500 ppm | ≤300 ppm |
Compressive strength | ≥50 MPa | ≥85 MPa | ≥90 MPa |
Flexural strength | ≥25 MPa | ≥39 MPa | ≥42MPa |
Resistivity | ≤12 μΩ·m | ≤10 μΩ·m | ≤10 μΩ·m |
Maximum operating temperature (inert atmosphere) | 1350°C |
1650°C |
1650°C |
Customizable Dimensions:
Standard boat-shaped molds: Length 200–1,500 mm × Width 100–800 mm × Height 50–500 mm
Wall Thickness: Standard 15–40 mm; Heavy-duty versions up to 80 mm
Cavity Customization: Single-cavity, multi-cavity (2–12 compartments), and custom-shaped casting runners
Accuracy Grade: General-purpose grade ±0.5 mm; Precision casting grade ±0.1 mm
▍Key Product Features
High dimensional accuracy: Manufactured using precision CNC machining, the cavity dimensions and inner wall flatness strictly meet specifications, ensuring smooth casting and discharge, and making it suitable for automated and semi-automated production lines.
Stable physical and chemical properties: With a low coefficient of thermal expansion, deformation at high temperatures is negligible, and the mold retains its original shape and volume even after long-term use.
Acid, alkali, and corrosion resistance: Resists corrosive fumes and molten metal erosion generated during metallurgical processes; the surface is resistant to corrosion and peeling.
Smooth surface for easy demolding: The smooth inner walls prevent molten metal from sticking, making discharge and cleaning simple and convenient, thereby reducing manual maintenance efforts.
Graphite Boat Box With Lid
Industrial Graphite Mold & Boat
▍Proper Use and Maintenance of Graphite Boats
To extend the service life of graphite boats, we recommend following these guidelines:
Slow heating: Avoid rapid heating, which can cause thermal shock cracking; it is recommended to heat the boat in tandem with the furnace.
Avoid mechanical impact: Handle graphite boats gently when removing or placing them; do not strike them.
Prompt slag removal: After each use, allow the boat to cool before removing any residual metal or furnace slag to prevent contamination or corrosion during subsequent use.
Store in a dry environment: Store in a dry environment to prevent moisture from affecting the service life.
Regular inspection: Replace immediately if obvious cracks or severe corrosion are detected.
▍Product Applications and Benefits
Metal-Melting-Casting
Vacuum-Induction-Furnace
Powder-Sintering-Graphite-Boat
Use Cases | Specific Uses | Benefits and Value |
Smelting and Casting of Non-Ferrous and Precious Metals | Smelting metals such as aluminum, copper, zinc, lead, gold, silver, and platinum | Graphite's non-wetting properties reduce slag adhesion and oxidation losses, thereby increasing metal yield; its high thermal conductivity shortens melting time and saves over 20% in energy consumption. The smooth inner walls ensure easy demolding and produce castings with a smooth surface; |
Induction Furnaces and Brazing Furnaces | As a workpiece for induction heating, or for use in brazing fixtures | Graphite is a highly efficient heat conductor that heats up rapidly; when used for brazing cemented carbide and diamond tools, it ensures uniform heating and produces strong, durable joints. |
Powder Metallurgy Sintering | Used to hold metal powder during high-temperature sintering and forming | Maintains dimensional stability at high temperatures; the boat does not deform; can be designed with multiple chambers or partitioned structures to enable batch sintering; offers excellent dimensional consistency. |
▍FAQ
Q1: What is the difference between a graphite boat and a graphite crucible? Which one should I choose?
A: The main differences lie in their shape and intended use. Graphite boats are typically open-top, boat-shaped, rectangular, or multi-chambered, making them suitable for holding and sintering sheets or small parts; they are also commonly used in induction heating applications. Graphite crucibles are bowl- or jar-shaped and are designed for melting and holding large quantities of metal. If you are melting kilograms of gold, silver, aluminum, or copper, we recommend using a crucible; if you are sintering powders, holding multiple small parts, or using them in an induction furnace, a graphite boat is more suitable. Of course, we can also customize shapes that fall between the two based on your drawings.
Q2: The furnace chamber dimensions at our factory are quite unique. Do you support custom-made irregularly shaped graphite boats?
A: Absolutely. We have a professional CNC machining team that can customize graphite boats, graphite fixtures, and matching connectors with various complex structures based on the furnace chamber drawings or samples you provide, ensuring a perfect fit for your equipment.
Q3: Do new graphite boats require pre-treatment before first use?
A: We recommend low-temperature drying before initial use to remove trace moisture from the product. Then, gradually heat it to the operating temperature to effectively extend its service life. We will also provide corresponding usage instructions.
Q4: Will smelting precious metals result in contamination or impurities?
A: No. Our products are made from high-purity, low-ash graphite raw materials with stable chemical properties. They do not react with precious metals such as gold or silver at high temperatures, nor do they release impurities, fully meeting the stringent requirements of precious metal casting.
Q5: What are your after-sales service and delivery lead times?
A: Standard stock models can be shipped promptly after ordering; delivery dates for custom models will be agreed upon based on complexity. Products undergo multiple quality inspections before leaving the factory. For quality issues not caused by human error, we will promptly address them and provide technical support regarding product usage and operational conditions throughout the entire process.
+86-795-4605783 
sales@nhdcarbon.com 
No. 966 of Tiangong South Avenue, High-tech Industrial Park, Fengxin County, Yichun City, Jiangxi Province, China.