How to Repair a Deformed Propeller? | Underwater Hydraulic Intervention Methods
How to Repair a Deformed Propeller? | Underwater Hydraulic Intervention Methods
Ship propellers are exposed to high forces and currents, which may cause bending, cracking, or structural deformation over time. These issues can reduce maneuverability and increase fuel consumption. Deformed propeller repair is often performed underwater by professional teams, eliminating the need for dry-docking and saving both time and cost.
What Is the Purpose of Propeller Repair?
The goal is to correct imbalances by restoring bent blades to their original shape as closely as possible. This reduces vibration, increases efficiency, and ensures safe navigation. A detailed underwater survey is essential before any repair to assess the severity of the deformation.
How Is the Hydraulic Method Applied?
The most common technique is underwater hydraulic pressing. Using specially designed hydraulic equipment, the diver carefully bends the damaged blades back into place. The operation is coordinated via a CCTV system, with real-time communication between the diver and the surface team. All angles and corrections are measured using precise instruments.
Equipment Used
- Hydraulic press system
- CCTV and communication units
- Measurement tools (goniometer, caliper, angle meter)
- Diver air system, pressure tanks, generator
- Propeller support and lifting straps
Repair Process Steps
- Damage assessment and measurement
- Corrective strategy planning
- Hydraulic system setup and underwater positioning
- Divers perform precise blade corrections
- Final measurement and symmetry check
- Operation is documented and submitted to class society
Advantages
- Eliminates dry-docking
- Allows ship to remain operational during repair
- Ensures high-precision correction
- Approved by classification societies
Conclusion
Deformed propeller repair can be safely performed underwater using expert divers and specialized hydraulic systems. This method preserves vessel performance, minimizes operational interruption, and ensures long-term durability of the propeller.