What are the precautions that you should do when the oil mist detector alarms?

How will you take action when oil mist detector alarm is on?

1. Inform to chief engineer.
2. Inform bridge, take the permission to stop the engine.
3. Gradually reduce the engine and then stop.
4. Cool down the engine.
5. Check the inside parts of the crankcase inspection.
6. Make necessary repair.
7. Reset OMD and start engine.

What is a oil mist detector?

Oil Mist Detectors protect large diesel, gas and dual fuel engines of all applications. They protect against heavy consequential damage due to oil mist explosions, a result of overheating of bearings or moving parts.

How do you maintain an oil mist detector?

Proper watch on all running gears temperature & pressure to be maintained. Blow through all sampling tubes of Oil Mist Detector (OMD) regularly. Zero adjustment & sensitivity of OMD to be checked regularly. Check for oil leakage at crankcase explosion relief doors & check for the operation by hand.

Why is it important to have oil mist detectors in a diesel engine?

Oil Mist Detectors protect large Diesel, Gas and Dual Fuel engines of all applications from heavy consequential damage due to oil mist explosions as a result of overheating of bearings or other moving parts.

What causes oil mist?

Formation of Oil Mist Oil mist may form when high pressure fuel oil, lubricating oil, hydraulic oil, or other oil is sprayed through a narrow crack, or when leaked oil connects with a high temperature surface, vaporizes, and comes in contact with low air temperature.

What is the purpose of oil mist detector onboard ship?

The Oil mist detector takes continuous samples from the main engine crankcase and check whether the sample concentrations of mist are well below the level at which a crankcase explosion can take place.

How does oil mist lubrication work?

Oil Mist is a centralized system in which the energy of compressed gas, usually air taken from the plant supply, is used to atomize oil. Oil is then conveyed by the air in a low pressure distribution system to multiple points of lubricant application. The compressed air is passed through a venturi.

What is the purpose of oil mist?

Oil Mist is created in the crankcase when the lubricating oil is splashed by moving and rotating parts of the engine. This oil mist reduces the flash point of the oil, allowing it to catch fire in presence of a hot spot.

What conditions can result if a build up of oil mist is allowed?

: The presence of an oil mist in the crankcase is the result of oil vaporisation caused by a hot spot. Explosive conditions can result if a build up of oil mist is allowed. The oil mist detector uses photoelectric cells to measure small increases in oil mist density.

How is the crankcase oil mist being formed?

When the oil comes in contact with the hot spot, these oil particles vaporize and smaller particles are formed. These particles move towards the colder region inside the crankcase space and when in contact with the cold region, form a white mist.

What causes crankcase explosion?

A crankcase explosion is caused by ignition of oil mist, itself created by the presence of a hot spot, which led to the evaporation of lubricating oil and its condensation into an oil mist. Its consequences can be severe, including death and serious injury to personnel and extensive damage to the engine.

Which type of engine is usually employed with mist lubrication system?

two-stroke engines
In two-stroke engines, mist lubrication is used where crankcase lubrication is not suitable. In a two-stroke engine, as the charge is compressed in the crankcase, it is not possible to have the lubricating oil in the sump. Hence, mist lubrication is adopted in practice.