Risk of potentail harm
To achieve this, the dredger is equipped with robust pumps and motors capable of extracting sand, clay, silt, and gravel efficiently. Despite ships being equipped with earthing systems, there's still a risk of flying sparks that could potentially harm the shaft bearings of propulsion engines. To mitigate this risk, investing in a specialized propeller shaft earthing kit is advisable. It helps in minimizing the electrical current passing through the bearings and gearbox to the hull, thereby reducing the likelihood of damage and early maintenance costs.
Components of the earthing system
A reliable propeller shaft earthing kit includes components designed with very low electrical resistance to effectively direct the electrical current from the propeller shaft to the ship's hull. The grounding device comprises a 75 mm. wide copper slip ring with a silver insert at its core. Running in parallel on this silver insert are two silver-graphite brushes (comprising 80% Ag), housed within a holder equipped with a pressing mechanism. These brushes play a crucial role in providing the drive shaft with the necessary low ohmic resistance, essential for minimizing the strong electrical current flow through the bearings and gearbox to the hull. The brush holder is securely connected to the ship's hull via a grounding cable.
Additional visual monitoring
Apart from the earthing set for propeller shafts, an additional monitoring set has been installed. This set serves the purpose of preventive maintenance by providing visual feedback on the condition of the propeller shaft grounding kit through an analog mV meter. Ideally, when the grounding kit is functioning correctly, the mV meter will display a reading below 50mV. However, if the reading exceeds 50mV, it indicates a malfunction within the PSE system, which could result from dirty or worn components or incorrect installation. Furthermore, the monitoring set can be equipped with a 4-20mA converter, adding an extra layer of alarm functionality. This feature enables the system to send a signal to the bridge in case the voltage difference rises too high due to a malfunction in the PS.
Related products
8047A-8047M Propeller Shaft Earthing and Monitoring System
- Complete system
- Propeller shaft earthing set
- Cabin monitoring system included
8047M Potential Monitoring Set
- Optimal functionality
- Including brushholder
- Analog mV-meter
8047A Propeller Shaft Earthing Set
- Complete monitoring set
- Indispensable for seagoing ships
- Directs electrical current that flows through the propeller shaft to the hull of the ship
Benefits of Propeller Shaft Earthing sets
The Propeller Shaft Earthing System minimizes electrical current flow through the bearings and gearbox, reducing maintenance costs. Additionally, the monitoring set with an analog mV meter helps visualize the system's condition, with values below 50mV indicating proper functioning. Althen offers specialized propeller shaft earthing kits and monitoring sets to safeguard against damage and ensure smooth operations. With our solutions, you can minimize maintenance costs and maximize performance.
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