Construction Materials for Ship Propeller
- Categoy: Especial Articles
- 3 Comment
- 18 December 2012
There exist quite various types of constructual materials that are used for ship propellers. Whereas, the propellers used by Merchant vessels are usually divided into two main groups based on the construction materials used. These are:
1. Aluminum – Bronze alloyed propellers
2. Manganese – Bronze alloyed propellers
Other than these, the propellers made of cast iron and cast steel are also rarely seen.
Aluminum – Bronze alloyed propellers are approximately 10% lighter compared to Manganese – Bronze alloyed propellers and in fact, this is a factor that reduces the ship’s daily fuel expenditure.
As it is known, cavitation occurs at the propellers and hence maintenance is time to time required. Because the material of the aluminum – bronze propeller is much more resistant to cavitation then the acquisition costs of the maintenance of Aluminum – Bronze alloyed propellers are quite lower than that of Manganese – Bronze alloyed propellers.
Aluminum – Bronze propellers can easily be maintained. Pittings due to cavitation can also easily be filled by the welding rods. Pre-heating is not necessary.
Aluminum – Bronze propellers are more expensive but during long-term operation they will pay off that difference.
Because of the low cost of the maintenance, the manganese – bronze alloyed propellers are widely used in commercial vessels, however due to all above stated reasons, the aluminum – bronze alloyed propellers are more advantageous than the manganese – bronze alloyed ones.
Chemical Composition
| Element / Propeller Material | Aluminium – Bronze | Manganese – Bronze |
| Copper | %78 – %81 | %55 – %60 |
| Zinc | %0.37 – %0.62 | %35 – %40 |
| Nickel | %4.5 – %5.5 | %4.3 |
| Iron | %3.5 – %5.5 | %0.9 – %2.0 |
| Manganese | %0.5 – %1.0 | %0.3 – %0.9 |
| Aluminum | %9.0 – %10.3 | %0.7 – %1.0 |
| Lead | %0.01 max. | %0.4 max. |
| Tin | – – – | %1.5 max |
| Other | %0.5 max | – – – |
Translation By: Huseyin Sahin
3 Comments
Jul 18 2013 tarihinde 06:50'de yazıldı.
i need to know that propellers can be designed using other than al-bronz nd mn-bronz
Sep 28 2013 tarihinde 06:21'de yazıldı.
Dear sir,
Is the Zinc Content in Aluminum Bronze is that low of the order less that 1.0%
Can you confirm it?
Thanks
Rajeev Vaghmare
India
Aug 25 2019 tarihinde 00:43'de yazıldı.
For thousands of years bronze has been an alloy of copper and tin.
Your article refers to propellers made of an alloy principally made up of copper and zinc.
That alloy is BRASS.
If a propeller was ordered in bronze as per your article and delivered in brass, also as per your article, what would be the liability if it failed and the ship was lost?