PRESSURE LUBRICATION SYSTEM G.R.K

 

Pressure Lubrication System

Brief Overview:
This system uses a pump to deliver oil under pressure to critical engine components, ensuring smooth operation, cooling, and protection.

Here’s a diagram depicting the flow of oil from the sump, through the pump, filter, galleries, and to moving parts.

Construction & Components:

·         Oil Sump / Pan: Reservoir at the engine’s base, storing the lubricating oil.

·         Oil Pickup & Strainer: Screened inlet that draws oil from the sump, preventing large particles from entering.

·         Oil Pump: Typically gear or rotor type, driven by the crankshaft or camshaft; pressurizes and circulates oil.

·         Oil Filter: Removes smaller impurities before oil enters engine passages. Pressure Relief Valve: Prevents excessive oil pressure by bypassing oil when needed.

·         Oil Galleries (Passages): Network of drilled passages distributing oil throughout engine.

·         Lubrication Targets: Includes crankshaft bearings, camshaft bearings, connecting rod bearings, piston pin, cylinder walls, valve train, etc.

·         Oil Return Paths: Gravity-fed return of oil from parts back to the sump.

Working Principle:

1.      Oil pump draws lubricant from the sump via the strainer.

2.      Oil passes through the filter, which removes contaminants.

3.      Pressurized oil enters the main galleries and is distributed to:

o    Main bearings via drilled passages.

o    Connecting rod big-end, through drilled holes from the crank journals.

o    Piston pin and small-end bearings, via further passages.

o    Valve gear and camshaft bearings, via separate lines.

4.      Excess or relief oil returns to sump by gravity.

5.      Pressure relief valve ensures system operates within safe pressure limits (around 2–4 MPa or ~2–4 kg/cm²).

Functional Advantages:

·         Provides consistent lubrication to all critical components, even under heavy loads.

·         Prevents metal-to-metal contact by maintaining hydrodynamic oil film.

·         Aids in cooling engine components via oil heat absorption and transfer.

·         Helps remove contaminants, protecting engine integrity.

Distributor-Type Fuel Injection Pump

Definition:

A distributor-type fuel injection pump is a rotary-type pump that meters and distributes high-pressure fuel to each cylinder of a diesel engine in the correct firing order.

Construction:

·         Cam Ring: Stationary outer ring with cam lobes.

·         Rotor & Plunger: Rotates inside the cam ring. The cam lobes cause the plunger to reciprocate and pressurize fuel.

·         Distributor Head: Has outlet ports connected to injectors.

·         Control Sleeve (or collar): Regulates fuel quantity.

·         Governor: Controls engine speed.

·         Timing Device: Advances or retards timing based on engine speed/load.

Working:

1.      Fuel intake: The low-pressure pump draws fuel from the tank.

2.      Pressurization: As the rotor turns inside the cam ring, the cam lobes cause the plunger to move inward, pressurizing the fuel.

3.      Distribution: The pressurized fuel is routed to the proper injector via the rotor's distributor ports.

4.      Fuel metering: The control sleeve adjusts the quantity of fuel injected based on load/speed.

5.      Timing and delivery: The governor and timing device ensure accurate timing and fuel delivery.

Advantages:

·         Compact and lightweight.

·         Suitable for 3 to 6-cylinder engines.

·         Precise control over fuel delivery.