Shaft grounding systems
Our shaft grounding systems drain any possible current sent out by the ICCP system and sacrificial anodes that may enter into the propeller shaft through the propeller. If left undrained, the potential difference between the propeller shaft and the hull may cause stray currents in the propeller shaft bearings or gearboxes, which could lead to corrosion and subsequent premature failure. Generally, each propeller shaft should be fitted with a grounding system.
The system consists of a set of silver brushes sliding over a copper slip ring with a silver strip. The silver brushes are pressed on the silver strip, ensuring maximum contact with the least resistance and thus allowing for optimal drainage of the current. The brush holders are mounted around shaft utilising spindles, of which we have two types:
- electrically isolated: brush and brush holder are connected to a power unit to monitor the shaft grounding system’s performance
- non-isolated: a bare metal spindle is used for draining the current to the hull