An Easy Guide to the Ship's Main Engine Lubricating Oil System.

 

Marine lube oil gadgets or any lubricating oil device in precise form works on 4 key sorts of lubrication; hydrodynamic, hydrostatic, boundary, and elastohydrodynamic lubrication.

 

Adequate lubrication of components is required to keep away from heat build up and wear; as a consequence, it enjoys an essential position in the working of ship equipment and the marine diesel engine in particular.

 

Many a time, engine lube oil is used to decide or predict the genuine fitness and situation of the engine. Lubricating oil is used for more than just lubrication; it also serves as a cooling medium, protects against corrosion, contains residue for filters, neutralises acid, and reduces wear.

 

According to a record posted by the Swedish membership and later confirmed by Alfa Laval, engine damage accounts for 34% of the renovation fee with only 24% of all equipment claims.

 

Further, in 48% of cases, lubrication failure or a lubricating oil device is the cause. Making it the top most motive for the most important engine failure. Therefore, it is vital to ensure ample lubrication at all times.

 

This is frequently performed through an environmentally friendly lubricating oil system. The lubricating oil device is in charge of creating a thin film of oil between two shifting components using a constant flow of lubricant, resulting in much less wear and friction between transferring parts.

 

The lube oil of a two-stroke marine engine consists of two main systems; cylinder lube oil gadget and the most important lubrication system. But for four-stroke marine engines, there is a single lubrication device for each crankcase and cylinder.

 

The predominant or crankcase lube oil machine consists of six principal elements; sump/drain tank, a strainer, lubricating pumps, a filter, a lube oil cooler, and a distribution manifold.

 

Under normal circumstances, the lube oil pump takes suction from the drain sump through a strainer and pumps it to the cooler via a filter. From the lube oil filter, it goes to special devices by means of a distribution manifold.

 

 

System for Lubricating Oil in Ship's Main Engines

 

The lube oil of a two-stroke marine engine consists of two systems: the cylinder lube oil gadget and the foremost lubrication system. But for four-stroke marine engines, there is a single lubrication machine for crankcase and cylinder lubrication.

 

The primary or crankcase lube oil gadget consists of six major elements; sump/drain tank, the strainer, the lubricating pumps, the filter, the lube oil cooler, and the distribution manifold.

 

Under everyday circumstances, the lube oil pump takes suction from the drain sump through a strainer and pumps it to the cooler by way of a filter. From lube oil filter it goes to unique devices through distribution manifold.

 

 

1) Sump for lubricating oil

 

The predominant engine lubricating oil sump is a giant house used to shop lubricant surrounded by using cofferdams. It is placed beneath the crankcase below the fundamental engine with a double bottom It is the place in the engine room the place all the lubricating oil wished for the fundamental engine operation is saved in one place. Typically, the lube oil pump draws suction from this oil sump. placed underneath the engine or a drain tank under the engine block. Furthermore, it is region the place all the returns tracesto allow the lube oil to meet and drain Therefore it is covered with fundamental gadgets such as degree gauge, heating pipes, sounding pipes, suction port, etc.

 

 

2 ) A Strainer

 

A strainer is a kind of filter with a giant mesh size; normally equipped at low stress or suction aspect of a pump in a lubricating oil system. Strainers are pretty handy to smooth and are hooked up to face up to very massive particle size. It wants to be cleaned normally in any other case the strain distinction throughout its aspects might also turn out to be un-operational. On ship’s foremost lube oil gadget a strainer is geared up on the suction of the oil pump internal the sump/drain tank. There it restricts the steel particles from getting into the system.

 

 

3) Pump for the main engine's lubricating oil

 

The lube oil gadget carries two screw pumps used to supply lubricating oil to all the components of the engine. Under everyday conditions, one pump is operational while the other is on standby. The pump takes suction from the engine sump/drain tank and pumps it to the distribution manifold through a filter and cooler. From the distribution manifold, the lube oil reaches a number of working devices of the engine, i.e., bearings, guides, underneath piston space, hydraulic strength grant unit, etc. These pumps are mainly engine-driven for slow-speed engines and motor-driven for medium- and high-speed engines. Further, the outlet valves are of the non-return type. In the event of a failure, the pumps are truly switched over, which has no effect on the operation of the lubricating oil system.

 

 

4) Filter for Lube Oil

 

Marine lubricant oil filters are installed immediately following the pumps on the discharge side. They are put in place to stop incredibly small particles from entering the system. Only one of the two filters is ever active, while the other is always ready to go. Metals and foreign particles that could increase friction and lead to wear are removed by the lubricating oil filter. Prior to the introduction of auto backwash and centrifuge filters, this friction was of the duplex filter type.

 

 

5 ) Lubrication Oil Coolers

 

The temperature of the working lube oil at the engine inlet is between 45 and 50 degrees Celsius. If it reaches or exceeds 60 degrees Celsius, an alarm will sound, and the engine will shut down gradually or completely, depending on the lubricant temperature.

 

Thus, to maintain lubricant temperatures at 45 degrees Celsius, lube oil coolers are mounted in the system. A typical lubricating oil cooler circulates lube oil through pipes surrounded by water.

 

A bypass valve is furnished to modify and manage the quantity of lubricant oil flowing via the cooler. This performs an essential function in increasing, reducing, or retaining the lube oil temperature. In the lubricating oil system, the cooler is mounted after the filter to decrease the stress drop throughout its inlet and outlet valves. Plus, if the cooler is hooked up earlier, there is a greater hazard of contaminants being settled in the lube oil cooler; affecting the rate of heat transfer.

 

In addition, having a cooler after the filter unit allows for higher filtration of much less viscous fluid/oil. This will increase the effectivity of the filtration unit and similarly reduce the viscosity drag.

 

 

6) Extensive Distribution

 

After the lube oil cooler, the lubricating oil goes to the distribution manifold, from which it is distributed to all the parts of the engine. The major part of the lube oil is then sent to the crosshead via a telescopic pipe.

 

The oil is further redirected from the crosshead to the bearings, guides, and area under the piston. It is now drilling to the bottom end bearing from the connecting rod's drillings.

 

The thrust bearing, chain drive, hydraulic power supply unit, exhaust valves, main bearings, and vibration dampeners all use the remaining oil. The return oil drain then empties into the oil sump.

 

 

System for Lubricating Cylinders

 

Unlike in excessive velocity or trunk-type engines, where there is a single lubrication gadget for each cylinder and crankcase lubrication, Modern two-stroke engines have a separate lubrication machine for their cylinders, liners, and piston rings. The cylinder lubricating oil gadget consists of four primary parts: a storage tank, a day tank, a distribution manifold, and a cylinder oil lubricator. The function of cylinder lubrication is to lubricate the liner and the piston ring.

 

This reduces the friction between the liner and the piston ring.Furthermore, it aids in the formation of a combustion seal and the neutralisation of acidic combustion by-products, reducing the amount of corrosion caused by acidic corrosion.In the trunk-type engine, this is achieved via splash lubrication.But in a slow-speed, massive marine engine, it is accomplished by using quills managed by means of a cylinder lubrication manipulation system.Having the right grade of cylinder oil is necessary for environment friendly engine operation.

 

 In a marine engine, the grade of lubricant used depends on the sulphur content of the gas oil.For example, a separate tank is stored to save separate lubricating oil for LSFO (low sulphur gasoline oil). At present, a marine engine runs on BN 30/40/50 for LSFO and BN 70/100 for HSFO.