Sage-Tips

What is the difference between the cylinder lube oil and the main lube oil?

For a trunk piston engine or four stroke engines, the main lube oil is responsible for piston and liner lubrication; hence it comes directly in contact with the combustible fuel. For two stroke engines, separate grade of lube oil is used as cylinder oil and its alkalinity depends on the engine fuel grade (HFO or LSFO).

Why cylinder oil is used in main engine?

Cylinder lubrication is required in order to lubricate the piston rings to reduce friction between the rings and liner, to provide a seal between the rings and the liner, and to reduce corrosive wear by neutralising the acidity of the products of combustion.

What are the values of TBN for a e crankcase oil?

What will you do as 2/E, if main engine lubricating oil temperature abnormally high?

• Inform bridge & reduce engine speed.
• Check engine overload or not (Exhaust temp:, fuel rack,..)
• Check L.O sump & L.O cooler & L.O purifier temperature (set value)
• Check L.O sump tank heating valve.

When main engine is running the lube oil in the sump tank must be sufficient to prevent from what?

The level of lubricating oil indicated in the sump when the main engine is running must be sufficient to prevent vortexing and ingress of air which can lead to bearing damage.

What is TBN in motor oil?

For years, Total Base Number (TBN or BN) has been used as one of the key measurements in the field to help determine remaining oil life by indicating the amount of performance-related additive left in the engine oil. In short, it helps you know when engine oil needs to be changed.

What are properties required for cylinder oil in liner lubrication?

It Must Be Able To Burn Cleanly, Therefore Leaving As Little As Possible Soft Deposits. It Must Pocess Adequate Viscosity At High Working Temperatures. It Must Form An Effective Seal In Conjunction With Piston Rings To Prevent Blow By.

What is a cylinder oil?

Definition of cylinder oil : a heavy grade of mineral lubricating oil especially : such an oil used for steam-engine cylinders and valves.

What is main engine system oil?

This system supplies lubricating oil to the engine bearings, and cooling oil to the pistons.

Is higher TBN better?

Total Base Number (TBN) Generally, oils with a higher TBN better neutralize acids and combustion by-products, resulting in longer oil life and improved protection against corrosion.

What happens when TBN is high?

High TBN oils can produce high ash content that can impair engine efficiency and cause loss of power, this will lead to excessive deposit build-up on pistons and valves. Ash deposit build-up on pistons and valves. Loss of oil stability. Polishing of cylinder line bores.

At what point cylinder oil is injected?

The cross-head diesel engine relies on the injection of cylinder lubricant through the liner wall to lubricate the piston. Ideally, the cylinder oil is injected between the 1st and 2nd piston rings when the piston is approaching the top of its stroke, and, after performing its duties, drains away to waste.

What TBN means?

Total base number
Total base number (TBN) refers to the quantity of acid, expressed in terms of the equivalent number of milligrams of potassium hydroxide required to neutralize all basic constituents present in 1 gram of sample. TBN determines the effectiveness of the control of acids formed during the combustion process.