Vessels such as ships and hovercraft have a large amount of rotating machinery, including engines, pumps, motors, gearboxes and fans. By using vibration sensors to continuously monitor the condition of this equipment, engineers can fine tune their maintenance schedules against the actual wear of components. The data can also be transmitted to the shore, so that in the event of a failure at sea the maintenance team can commence preparations before the vessel even docks to ensure the quickest possible return to service.
The marine environment is harsh and corrosive, so it is essential that sensors have housings that can prevent the ingress of moisture, dust, oils and other contaminants as well as resisting corrosion. For constant exposure to marine environments, high corrosion resistant duplex stainless steels can be specified.
Sealing around integral stainless steel braided cables has an IP rating of IP66, allowing regular soaking without leakage into the accelerometer case. However, for long term constant exposure to water a fully IP68 submersible version should be specified.
A typical submersible sensor is Monitran’s general purpose constant-current 1100W with AC outputs. They can be fed into a bulkhead-mounted waterproof MTN/5000 condition monitoring unit containing the appropriate number of signal conditioning units.