In internal combustion engines or any machinery that involves moving parts, it needs lubrication for the basic reason that it will avoid wear and tear in between moving parts. In shipping where the size of the engines is huge, lubrication requirements are specific and much important. On board ship mainly lubrication is needed for main engines in large scale, so I have discussed this whole article in keeping marine engines at the center. So let’ first see what the functions of lubricants are.
Use of Lubricants in Engine Lubrication
First of all it forms a medium between the two surfaces and thus avoids any metal to metal contact. It reduces static and dynamic friction, and reduces the wear and tear between the parts.
A lubricant also helps to remove to the heat from the bearing which is developed to the high speed of moving parts. So, we are getting a cooling effect also and that is the reason why lubricants are designed to withstand high temperatures.
To protect the metal from getting corroded, lubricants avoid any type of corrosion taking place in the combustion chamber of the engine. Also it protects the engine from cold corrosion.
During combustion and engine being in motion, lots of carbon deposits are accumulated at the end of the moving surfaces. Lubricants have detergency quality and they tend to wash away these carbon deposits and thus avoid deposition of carbon particle locally.
It dampens the load acting on the bearings and also reduced noise that is caused when two surfaces are moving against each other.
Another unique function of lubricants is that they act as a sealant and avoid blow by gases being passed from the scavenge
space to the crankcase space.
They take up the high stresses when the load on the engine increases. So these were some of the functions of lubricants in engine lubrication.
Types of Lubrication in Engines
Boundary or thin film lubrication
Partial Film Lubrication
It is said that type of lubrication that is in the middle of Hydrodynamic and Boundary lubrication is an aid to partial film lubrication.
Elasto hydrodynamic Lubrication