C90700 Bronze Bushes
C90700 Bronze Bushes
Self-lubricating bronze bearings are engineered for applications where external lubrication is impractical. Solid lubricants are compressed and molded directly into the bearing to guarantee a maintenance-free product. No additional lubrication is necessary.
ZCuSn10Zn2 (SAE 65 / ASTM C90700) Continuous Casting Bronze
ZCuSn10Zn2 is commonly cross-referenced internationally to SAE 65 / UNS C90700 (often described as a high‑tin bronze). In North America, C90700 is widely supplied as continuous-cast bronze bar/tube/plate under ASTM B505 (continuous cast copper alloy shapes), then finish‑machined into bearing components.
Across industrial supply and foundry datasheets, C90700 is repeatedly positioned for high strength, heavy loads, and relatively low speeds, especially where motion is slow, oscillating, or intermittent—conditions that are typical in many heavy marine mechanical joints (e.g., large pins, trunnions, and shafts).
Key practical reasons it is selected for marine heavy-duty parts include:
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High load-carrying capability at low sliding speed (typical of many marine hinges and pin joints).
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Good wear resistance in bearing service.
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Availability as continuous-cast tube/bar, allowing large bushings/sleeves to be machined with reliable, consistent stock.
Attributes and Advantages
C90700 Tin Bronze distinguishes itself with its formidable and sturdy attributes, providing commendable corrosion resistance, notably in marine surroundings. Its prowess as a bearing material stems from its durability against wear and fatigue. The alloy presents moderate machinability, rendering it apt for diverse manufacturing processes.
A pivotal advantage of C90700 lies in its resistance to dezincification, a phenomenon where zinc seeps out of brass or bronze, resulting in brittleness and weakness over time. This property assures sustained durability and reliability of components fashioned from this alloy.
1. Corrosion Resistance: C90700 bronze exhibits exceptional resistance to corrosion, especially in seawater environments. This quality renders it an optimal selection for marine applications, safeguarding against damage from saltwater and harsh chemicals.
2. Wear and Fatigue Resistance: Renowned for its robustness against wear and fatigue, C90700 bronze proves indispensable for components subjected to heavy loads and stresses. Its resilience makes it ideal for enduring applications like gears and worm wheels, ensuring long-term durability.
3. Machinability: With moderate machinability, C90700 bronze facilitates easier fabrication and shaping into desired configurations, catering to diverse application requirements.
4. Strength: Possessing notable strength and hardness, this alloy furnishes outstanding mechanical properties crucial for various industrial applications, including bearings, bushings, and mechanical components.
5. Versatility: Embracing a broad spectrum of applications ranging from gears and bearings to marine fittings and piston rings, C90700 bronze stands as a versatile material, meeting the demands of multiple industries with aplomb.
6. Cost-Effectiveness: Offering a more economical alternative compared to materials like aluminum bronzes, C90700 bronze emerges as a pragmatic choice across applications where cost considerations weigh heavily.
7. Suitability for High-Speed and High-Load Applications: Tailored for tasks necessitating high strength and wear resistance under intense speeds and heavy loads, C90700 bronze excels in demanding environments, ensuring steadfast performance.
Applications of C90700 Bronze Bushes
C90700 Tin Bronze finds extensive employment in critical sectors such as:
- Gears and worm wheels
- Bearings
- Marine fittings
- Piston rings
- Pump components
These applications benefit from the alloy’s strength, wear resistance, and corrosion protection, positioning it as a preferred choice for parts subjected to harsh conditions or necessitating prolonged service life.
Specific marine machinery locations where C90700 bushings are used
Below are high-probability, real-world heavy marine machinery locations where a C90700 (SAE 65) continuous-cast bronze bushing/liner is a good fit, because the duty cycle matches “heavy load + low speed + oscillation/intermittent movement.”
A) Rudder system (steering): rudder stock / pintle bushings
Component form: flanged bushing or sleeve bushing
Where it sits:
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In the rudder horn / rudder carrier or pintle/gudgeon joint, as the sacrificial bearing surface between steel pin/stock and steel housing.
Why the alloy fits:
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Rudder motion is typically slow and oscillatory, but loads from hydrodynamic forces can be very high.
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Bushings allow controlled clearance, alignment, and service replacement during maintenance.
B) Deck crane, A‑frame, and heavy lifting equipment: boom foot pin / luffing joints
Component form: heavy-wall sleeve bushing, often with grease grooves and seals
Where it sits:
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At boom foot pins, sheave pin joints, luffing cylinder pin joints, and other articulated joints where a large pin rotates or oscillates within a bore.
Why the alloy fits:
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These joints see very high bearing pressure with relatively low sliding speed.
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Bronze bushings can be made thick and robust and are straightforward to replace.
C) Winches, windlasses, and capstans: shaft support bushings
Component form: sleeve bearing / bearing liner
Where it sits:
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Supporting drum shafts, worm gear shafts, or auxiliary pivots in deck machinery.
Why the alloy fits:
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C90700 is also frequently cited for worm gear and gearbox applications, aligning with deck machinery drive trains.
Note: Exact equipment design varies by OEM and class rules; the “bushing at a heavily loaded steel pin/shaft interface” pattern is the common thread.
Specifications and Chemical Composition
C90700 Tin Bronze complies with various standards, including ASTM B 505 Alloy 90700, SAE 65, ASTM B 271 Alloy 90700, SAE J461, SAE J462, QQC 390 Alloy 90700, and ASTM B427 Alloy 90700. These standards uphold the alloy’s quality and uniformity for industrial applications.
The chemical composition primarily comprises copper (Cu) with substantial tin (Sn), alongside potential inclusion of other elements like zinc (Zn), lead (Pb), iron (Fe), phosphorus (P), nickel (Ni), aluminum (Al), and antimony (Sb). The precise composition is:
- Copper (Cu): 88.00-90.00%
- Tin (Sn): Significant but unspecified percentage
- Other elements: Present in minor proportions to enhance the alloy’s attributes
This composition fosters exceptional mechanical and physical properties, apt for demanding applications.
Mechanical Properties
C90700 Tin Bronze exhibits notable strength and commendable machinability, rendering it suitable for crafting intricate parts. While specifics such as tensile strength, yield strength, and hardness may fluctuate based on manufacturing procedures and treatments, the alloy generally furnishes a harmonious blend of strength and ductility for industrial usage.
In essence, C90700 Tin Bronze bushes command esteem across various industries for their robustness, corrosion resistance, and wear resilience. Their extensive array of applications, spanning from marine fittings to bearings and gears, underscores the alloy’s versatility and dependability in challenging environments.
