Q. Give A Brief Description About Alpha Lubricator?
Ans: Advent Of New Technology And Increment In The Prices Of Oil Forced To Cut The Running Costs Of Marine Machineries. Alpha Lubricator Can Be Considered As The Result Of The Same. It Hasn't Only Reduced The Operational Cost But Also Optimized The Engine Performance. It Is Modern Method Of Controlled And Calibrated Cylinder Lubrication. Individual Cylinder L.O. Quantity Control Can Be Achieved In Alpha Lubricators. Oil Is Supplied To The Liner Walls Through Quills And Quantity Of Oil Is Controlled By Changing Position Of Central Piston In The Lubricator Unit.
Q. What Are The Main Components Of Alpha Lubricators?
Ans: 1. Pump Station And Starter Panel: Two Pumps (individually Operating) Take Suction From Suction Tanks, Through Filters. Heating Coil Is Also Fitted In The Tanks To Ensure Inlet Temperature In Cold Time. Power Is Supplied To The Pumps Trough Two Circuit Breakers, One Supplying Each Pump.
2. Lubricator Unit: It Is Consisting Of Two Or One Lubricator (depending On Cylinder Bore). Each Lubricator Unit Equipped With One Accumulator With Nitrogen Pressure Of 25-30 Bar On The Inlet Side And One At Outlet Side With A Pre Pressure Of 1.5 Bars For Every Lubricator. A Feed Back Peak Up And Solenoid Valve Is Also Fitted In The Lubricator Unit.
3. Alpha Lubricator Control Unit (ALCU)
4. Load Transmitter: It Is Connected To The Fuel Rack, Transmitting Fuel Rack Index (%) To Master Control Unit (MCU), Calculates Engine Load And Detects Rpm.
5. Trigger System (Shaft Encoder): Shaft Encoder Is Connected At The Fore End The Fore End Of The Crank Shaft Transmits Signal To The Computer Panel. It Helps To Decide Piston Position Hence Injection Timing.
6. Back Up Trigger System: Two Tacho Pick Ups In A Box At Turning Wheel Transmitting Engine Rpm To The Back Up Control Unit (BCU). It Helps BCU To Meter Oil Amount As Per The Engine Rpm When MCU Gets Failed. It Is Also Connected To MCU For Surveillance Purpose.
7. Human Machine Interface (HMI): It Helps Engineer Officers To Do Various Adjustments And Controls.
– Lubrication Feed Rate Adjustment
– Control Of Pump Station
– Display Various Alarms
– Shows Amount Of Oil Consumed
Q. What Are The Main Advantages Of Alpha Lubricator?
Ans: 1. Reduction In SLOC (up To 0.7 Gm/Kwh) Hence Reduction In Cost.
2. Optimum Distribution Of Oil On The Cylinder Walls.
3. Less Deposits In Combustion And Scavenge Spaces.
4. Better Pre Lubrication Can Be Achieved.
5. Individual Cylinder Feed Rate Adjustment.
Q. Give A Brief Description Of Its Working Principle?
Ans: 1. Pump Supplies Oil To The Alpha Lubricators At A Pressure Of 40-45 Bar (varies According To The Cyl. Bore)
2. Injection Timing Decided By The Tacho Peak Ups And MCU Commence The Oil Injection By Activating Solenoid Valve On The Relevant Lubricator, Which Allows Oil To Flow To The Liner Walls Through Quills.
3. A Feed Back Signal By Led Confirms Oil Injection.
4. During Normal Operation System Is Controlled By MCU And If Any Failure Occurs, BCU Automatically Takes Over.
**BCU Is Based On Random Time Injection. However, Amount Of Injection Depends On The Engine Rpm. In BCU Mode Injection Is 50% Surplus Of The Normally Required At That Rpm.