Centrifugal casting Bronze

Centrifugal casting bronze is a high-quality manufacturing process used to create cylindrical components. This technique spins a mold at 300 to 3000 RPM while pouring in molten material, which spreads across the mold’s surface to shape the product. It’s ideal for making large pipes, cylinder liners, and hollow parts from various materials, especially metals and bronze alloys like tin bronze and bronze rings. Metals like cast irons, steel alloys, and non-ferrous metals, including bronze, can acquire excellent heat-resistant properties through this process.

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Specializing in the Centrifugal Casting Bronze production of various grades of castings with a rotating center

Centrifugal casting for bronze bearing parts involves pouring molten bronze into a rotating mold, which can be vertical or horizontal depending on the desired shape. The rotation spreads the molten bronze along the mold walls with forces over 100 times gravity. As the bronze cools and solidifies from the outside in, denser materials move outward, pushing impurities and lighter materials to the center. This process ensures that the denser, purer bronze forms the exterior, while impurities are concentrated near the inner diameter, which is later machined to achieve the desired internal dimensions. Our specialists are available to answer questions about product details or advise on the best alloy for your application.

Precision bearings, Types of metal alloys

The mold design includes a central sprue connected to multiple cavities by runners, directing molten bronze to fill each cavity. Pouring can begin with the mold in motion or stationary and continues until the required bronze volume, including materials for runners and sprue, is used. Rotation continues post-pour to ensure the bronze spreads evenly as it solidifies. Once solidified, rotation stops, and the cast part, nearly flawless and free from defects or porosity, is removed. This process ensures that bronze bearing bushings produced by centrifugal casting meet high standards of precision and integrity. Alloy Casting Manufacturer – China Alloy Casting Factory!

BRONZE WORM GEAR cual10ni alloy code
C90700 (SAE 65) Bronze Bearing groove bearing plain sliding bearing bushing flange

Centrifugal casting bronze Advantages

This method yields parts with excellent metallurgical qualities, such as superior grain structure and directional solidification, making it perfect for hollow cylindrical shapes like pipes, tubes, and rings. Centrifugal casting enhances uniformity and mechanical properties, reducing defects and producing bronze components with outstanding strength and durability.

Copper & Centrifugal Casting Bronze Parts across various industries, including material handling, ocean energy, mining, mineral processing, cement, and others.

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Stay competitive in extreme conditions

Amid industry risks, capital demands, and volatility, increasing productivity and profitability remains crucial. Adapting with customized solutions is essential to withstand intense global competition.

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Material handling

Our extensive range of centrifugal casting bronze bushings and asset management solutions is crafted to enhance productivity and reliability.

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Ocean energy

Enhance reliability, availability, and maintainability for future technologies with our expertly designed, self-lubricating centrifugal cast copper bearings, tailored for demanding seawater environments. Our custom solutions boost operational efficiency and set the stage for your future success.

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Mining, mineral processing and cement

Mining, mineral processing, and cement production operate in harsh, remote environments, facing heat, contaminants, vibration, heavy loads, and high production demands. Reliable bronze parts are crucial to ensure uptime, reduce maintenance costs, and enhance safety.

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Easy-to-operate pumps keep equipment running smoothly

These cost-effective bronze bushings feature a compact, lightweight design, ideal for oil and fluid grease use. Crafted from durable Centrifugal Casting Bronze, they ensure reliability in demanding applications.

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Wind energy

Stay competitive and tackle technical challenges in the wind industry, which is under pressure to reduce the cost per megawatt-hour. This requires improving turbine centrifugal cast bronze bearings, enhancing performance and reliability, and minimizing maintenance costs. We provide self-lubricating copper bearings to optimize turbine efficiency, reliability, and energy output. Our products include precision-engineered bearings, bronze rings, and self-lubricating sliders that support more cost-effective wind energy production and lower lubricant use.

Centrifugal, and Centrifugal Casting Bronze alloy, Type of material

Comparative Casting Methods

Various casting methods are used for ferrous and non-ferrous metals, each with specific advantages and disadvantages. Below is a brief description of some common methods along with relevant data.

Sand Casting: This method involves packing moist bonded sand or resin-coated sand around a wooden or metal pattern of the item to be cast. After removing the pattern, the resulting cavity is filled with molten bronze. Once cooled, the castings are separated from the gate and runner system.

Advantages:

  • Versatility in casting metals of any type—ferrous or non-ferrous—without restrictions on size, weight, or shape.
  • Cost-effective for both small and large production runs, including lower tooling costs.

Disadvantages:

  • Achieving close tolerances is challenging; additional machining is often necessary.
  • Generally results in interconnected porosity and a rough surface finish around 1000 RMS.
  • Typical tolerances range from ±1/32 inch to ±.090 inch or greater across parting lines.

Permanent Mold Casting: In this method, mold cavities are machined from nickel steel or cast-iron blocks, designed for repeated use. Steel cores or intricate sand cores are employed, the latter being expendable due to casting heat. The molten bronze is poured into the cavity by gravity or under low-vacuum pressure to minimize turbulence.

Advantages:

  • Offers good dimensional accuracy and rapid chilling results in a fine grain structure.
  • Achievable casting tolerances range from ±.010 to ±.015 per side, with parting lines held to about ±.030.

Disadvantages:

  • Typically limited to non-ferrous alloys.
  • Size, shape, and complexity are somewhat restricted, although thinner sections than sand castings can be achieved.
  • Requires a moderate annual production volume (between 1,000 to 50,000 pieces) to justify the high tooling costs.
  • Each casting must have a gate and riser, which can affect the yield’s effectiveness.

These methods represent just a snapshot of the broad field of casting, each suited for different types of production needs and metal characteristics.

Comparative Casting Methods

Centrifugal Casting: This method involves using steel or cast-iron dies into which molten metal is poured while the die rotates or spins. After pouring, water spray is directed onto the rotating die to cool it more rapidly.

Advantages:

  • The centrifugal force ensures that the metal is free of porosity and is more dense, making it ideal for applications requiring resistance to heavy loads and impacts.
  • Suitable for both ferrous and non-ferrous alloys, this method produces alloys that can withstand substantial hydraulic pressures without leaking.

Disadvantages:

  • Although the die sets a controlled stock allowance, machining is typically required to remove the rough surface finish and excess material.

Continuous Casting Method: In this process, a die made of carbon graphite, surrounded by a cooling jacket through which water flows, is used to chill and solidify the cast tube, bar, or shape as it exits the furnace by gravity.

Advantages:

  • Minimal stock allowance, usually within plus-or-minus .015, reduces the need for extensive machining.
  • Various shapes can be cast to near-final dimensions without the need for precision machining.
  • The structure is generally suitable for radiographic tests and can withstand substantial hydraulic pressure without leaking.

Disadvantages:

  • High initial cost and substantial space requirements.
  • Graphite dies must be replaced after each run, and each size requires a separate cooling jacket.

Die Casting: Molten metal is forced into closed steel dies at high velocities by the application of pressure.

Advantages:

  • Provides excellent dimensional accuracy, with tolerances across parting lines of plus-or-minus .005 and extremities ranging from plus-or-minus .001 to .003.
  • Surface finishes of 100 RMS or less are typically achieved.

Disadvantages:

  • High production volumes (from 20,000 to over a million pieces) are necessary to offset the high cost of die casting.
  • Limited to non-ferrous metals, and porosity may occur due to entrapped air in the die.
  • Size limitations are typically around 3 feet square and under 15.0 pounds.

Investment Casting: This method uses various ferrous and non-ferrous materials to create a wax or thermoplastic pattern, which is expendable.

Advantages:

  • No parting line or draft is needed.
  • Surface finishes are typically less than 125 RMS.
  • Capable of casting complex shapes not possible with other methods.
  • Economical when it eliminates two or three machining operations.
  • Tooling costs are lower than those for pressure-die casting.

Disadvantages:

  • Despite fewer design limitations in terms of shape and size, the cost per pound for this process is comparatively high.

These casting methods represent a broad spectrum of techniques, each with unique benefits and challenges, catering to various industrial applications and material specifications.

Material composition and properties
Code JDB650 JDB650 S1 JDB650 S2 JDB650 S3 JDB650 S4 JDB (HT250) JDB (Gcr15)
material grade CuZn25Al6

Fe3Mn3		 CuZn25Al6Fe3Mn3 CuAl9Fe4Ni4Mn2 CuSn5Pb5Zn5 CuSn12 HT250 Gcr15
density 8.0 8.0 8.5 8.9 9.05 7.0 7.8
hardness HB >210 >250 >150 >70 >80 >190 HRC>58
tensile strength N/mm2 >750 >800 >800 >200 >260 >250 >1500
Elongation % >12 >8 >15 >10 >8 >5 >15
coefficient of linear expansion 10-5/°C 1.9 1.9 1.9 1.8 1.8 1.0 1.1
Operating temperature °C -40~+300 -40~+150 -40~+400 -40~+400 -40~+400 -40~+400 -40~+400
Maximum dynamic load N/mm2 100 120 150 60 70 90 200
Maximum line speed m/min (Dry) 15 15 20 10 10 8 5
Max.PV N/mm2 *m/min 200 200 60 60 80 40 150
Compression Set 300N/mm2 <0.01 <0.005 <0.04 <0.05 <0.005 <0.015 <0.002

Regarding machinability, high-strength yellow brass has a rating of 65 percent on the machining index, indicating excellent machinability. This characteristic implies that the material can be effortlessly shaped, cut, or drilled, which makes it an ideal option for detailed and precise applications.

If you’re in search of bronze casting alloys, viiplus offers high-quality alloys and exceptional customer service.

We provide a variety of products for specific applications, from standard bronze to specialty alloys.

Our experts are always ready to address any questions or concerns about our products and services.

Contact us now to discover how we can assist you with your bronze casting project.

Material correspondence table
Material code
Codes		 China
GB1176-87		 internationality
ISO 1338		 Germany
DIN		 Japan
JIS		 U.S.
ASTM(UNS)		 U.K.
BS		 France
NF		 Applicable
JDB650
High strength alloy copper		 ZCuZn25Al6
Fe3Mn3		 GCuZn25Al6
Fe3Mn3		 DIN1709
G-CuZn25Al5		 H5102
CAC304		 B30-92
C86300		 HTB2 High load, low speed, general use
JDB650 S1
High strength alloy copper		 ZCuZn25Al6
Fe3Mn3		 GCuZn25Al6
Fe3Mn3		 DIN1709
G-CuZn25Al5		 H5102
CAC304		 B30-92
C86300		 HTB2 Ultra high load, low speed, high load
JDB650 S2
Cast tin bronze		 ZCuSn5
Pb5Zn5		 GCuPb5
Sn5Zn5		 DIN1705
G-CuSn5ZnPb		 H5111
BC6		 B30-92
C83600		 LG2 CuPb5
Sn5Zn5		 medium load, low speed
JDB650 S3
Cast aluminum bronze		 ZCuAl9Fe4
Ni4Mn2		 GCuAl10
FeNi5		 DIN17656
G-CuAl10Ni		 H5114
AlBC3		 B30-92
C95500		 AB2 CuAl10
Fe5Ni5		 Medium load, medium speed, general use
JDB(HT250)
cast iron		 GB5675-85
HT250		 FC250 ASTM
Class40		 medium load, low speed

Effect of Casting Method on Bronze Alloys

The casting method significantly influences the properties of bronze alloys, including grain size, density, hardness, and mechanical and physical properties. The selection of a casting method should be aligned with the intended service conditions of the bronze alloy, such as the type of load (steady, intermittent, or shock), surface speeds, and other crucial factors.

Sand Casting In this method, molten bronze is poured into a sand mold which insulates thermally, causing the casting to cool slowly. This gradual cooling enlarges the grain size, typically resulting in a lower density and structural integrity compared to other casting methods.

Permanent Mold Casting This method employs nickel steel or cast-iron molds that rapidly cool the molten bronze, leading to a faster solidification and a finer grain size. The result is a casting with no interconnected porosity, a finer surface finish, and enhanced physical and mechanical properties.

Centrifugal Casting Here, molten metal is poured into a rotating die, where centrifugal force drives the metal against the die walls, eliminating porosity. Rapid cooling achieved by water spray further refines the grain size, enhancing the physical and mechanical properties over those obtained by sand casting or permanent mold casting.

Continuous Casting Continuous casting involves molten metal flowing through a graphite die, immediately chilled by a surrounding cooling jacket. This process further reduces the grain size, significantly enhancing the mechanical strength and durability of the casting. Typical increases include tensile and yield strengths by 5,000 to 10,000 PSI and hardness by 10 to 20 Brinell points.

Enhancing Properties Through Extrusion and Forging While casting methods provide foundational properties, extrusion and forging can further refine the grain size, although these processes are special operations beyond the capability of basic casting methods.

Wear Resistance of Bronze Bearing Materials

Bronze bearings are favored for their excellent wear resistance, critical for maintaining performance across various applications. Even when lubricant films fail, leading to direct contact and wear, the resilience of the material is paramount.

Comparison of Wear Resistance Among Bronze Alloys

  • Aluminum Bronze CDA 954 stands out with the highest wear resistance.
  • Comparatively, CDA 954 is 3.9 times more wear-resistant than CDA 938.
  • CDA 863 has 2.5 times the wear resistance of CDA 938.
  • CDA 905 shows an improvement of 1.9 times over CDA 938.
  • CDA 932 is found to be 1.2 times more wear-resistant than CDA 938.

Factors Influencing Wear Resistance

  • Material Composition: Varying levels of strength, hardness, and ductility in different bronze alloys affect their wear performance.
  • Lubrication Conditions: Effective lubrication significantly reduces wear, whereas inadequate lubrication increases friction and wear rates.
  • Operating Environment: External conditions like temperature, contaminants, and bearing alignment play a significant role in wear resistance.
  • Mechanical Properties: Alloys with higher tensile and yield strengths generally exhibit better wear resistance.

Conclusion

Aluminum bronzes, particularly CDA 954, are highly valued for their superior wear resistance, ideal for bearing applications where longevity and reliability are crucial. Understanding the comparative performance of various bronze alloys helps in selecting the best material for specific operational needs.

Centrifugal Cast Bronze Bearings and Copper Tubes

Centrifugal casting is an efficient casting process primarily used for manufacturing high-strength and wear-resistant copper alloy products. Below is a detailed introduction to this process.

Centrifugal Casting Process
Centrifugal casting involves pouring molten metal into a rapidly rotating mold, using centrifugal force to evenly distribute the metal and allow it to solidify. This method offers the following advantages:

  • Good Density: Due to the centrifugal force, the crystallization of the metal occurs sequentially from the mold wall towards the inner surface, reducing the formation of air bubbles and inclusions. This improves the density and strength of the cast product.
  • Material Savings: Centrifugal casting does not require complex pouring systems or risers, resulting in higher material utilization and lower production costs.
  • Strong Adaptability: It can cast copper alloy products in various shapes and sizes, making it especially suitable for large components such as copper bushings and bearing sleeves.

Characteristics of Bronze Materials
Bronze is an alloy primarily composed of copper and tin, known for its excellent mechanical properties and corrosion resistance. Common types of bronze include:

  • Leaded Bronze: Contains lead and is used for manufacturing bearings and other components requiring good wear resistance.
  • Aluminum Bronze: Known for its high wear resistance and corrosion resistance, commonly used in high-load applications such as ship propellers.

Production Process
The typical production process for centrifugal cast bronze bearings and copper tubes is as follows:

  1. Material Preparation: Raw materials are prepared according to the required alloy composition (such as Pb, Sn, Cu, etc.).
  2. Melting: The raw materials are heated in a furnace until molten, usually at a temperature range of 1100°C to 1150°C.
  3. Casting: The molten metal is rapidly poured into the rotating mold. Due to the high speed of rotation, the metal is forced against the mold walls, forming the desired shape as it cools.
  4. Cooling and Removal: Once the metal has fully solidified, the rotation is stopped, and the cast product is removed. Subsequent processing may include removing excess material or surface treatments.

Applications
Centrifugal cast bronze bearings and copper tubes are widely used in:

  • Marine components
  • Industrial equipment
  • Automotive parts
  • High-load mechanical parts

This process not only enhances the quality of the products but also effectively reduces production costs, making it a crucial part of modern manufacturing industries.

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Applications of Centrifugal Casting

Bronze is a strong, durable metal known for its corrosion resistance, making it widely used in statues, coins, industrial machinery, and high-strength components in the automotive and marine industries. It is also popular for sculptures and art pieces.

Bronze Parts Made by Centrifugal Casting

Centrifugal casting is a widely used technique for casting bronze alloys, particularly for intricate small parts. In this process, the mold is spun while molten bronze is poured into its center, allowing centrifugal force to press the bronze against the mold walls for a smooth finish. Once cooled, the mold is removed to unveil the final product. This method provides precise control, resulting in highly accurate replicas.

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Continuously Cast Bronze Bearing

Continuous casting is a modern technique in which molten bronze is continuously poured into a mold to produce long shapes, such as tubes and pipes. A roller system controls the speed and cooling of the bronze as it solidifies. The finished product is then cut to specified lengths, ensuring a smooth bronze flow. This efficient method is favored by manufacturers of large quantities of bronze alloys.

Continuous Cast Bronze Alloy

Bronze alloys can be cast using several methods, each with distinct advantages and disadvantages. Sand casting is traditional and economical, while centrifugal casting offers high precision for small, intricate pieces. Continuous casting is efficient for producing long shapes, making it suitable for large-scale production. Regardless of the method, bronze casting remains a timeless and captivating technique used in a wide range of products, from everyday items to industrial machinery.

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