- Severe damage to complete bearing area.
- Cavities are usually around at low pressure areas i.e. oil groove or oil holes.
- Caused by an implosion of gas or air bubbles released from a lubricating oil film under particular conditions
- The pressure set up locally during theses implosions are very high , possibly 220 bar & may cause a pitting / cavitation
- Prevention – May be reduced by viscous oil because of damping effect high viscous oil & viscosity must be in limit.
1. High cost: Manganese bronze is a costly alloy, making it less economical for large propellers. 2. Low strength-to-weight ratio: Compared to other propeller materials like nickel-aluminum bronze or stainless steel, manganese bronze has a lower strength-to-weight ratio. 3. Susceptible to corrosion: Manganese bronze can corrode in seawater, especially when exposed to high velocities and turbulence. 4. Poor cavitation resistance: Manganese bronze is more prone to cavitation damage than other materials. 5. Difficult to cast and machine: Manganese bronze is challenging to cast and machine, making it less desirable for complex propeller geometries. 6. Limited weldability: Manganese bronze has poor weldability, making repairs and modifications difficult. Nickel-aluminum bronze or stainless steel are commonly used for propellers due to their: - High strength and durability - Excellent corrosion resistance - Good cavitation resistance - Ease of casting and machining - Weldability
Sir, What about cavitation erosion on the water side of the engine cylinder liners ?
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