Tuesday, December 17, 2013

Single Phasing of a Motor?

Single Phasing of a Motor?

Single Phasing is where one of the 3-phase's supplying the Motor becomes disconnected.  The Motor will continue to run if this happens and can result in Motor Burnout.  The effect of Single Phasing is to increase the Current in the two remaining Lines and cause the Motor to become very noisy due to uneven Torque produced

How is 15ppm reached in an Oily Water Separator?

How is 15ppm reached in an Oily Water Separator?


15ppm is achieved in an Oily Water Separator by normally passing through a Two Stage Separator where in the first stage Oil/Water is passed into the coarse separating compartment. Here some oil will rise to the top of the Compartment due to its lower density, Heating Coils may aid this. 
  The remaining Oil/Water will flow down into the Fine separating Compartment and moves slowly between Catch Plates.  More Oil will separate out onto the underside of these Plates and travel outwards until free to rise to the oil collecting space. 
  The almost Oil Free Water (usually being at 100ppm at this stage) will then pass to the second stage of the separator, which is a Filter Unit comprising of two Filter Units.  
The first Filter Stage removes Physical Impurities present and promotes some Fine Separation. 
  The second Stage Filter uses Coalescer Inserts to achieve the fina, Oil/Water Mixture leaving this Stage at less than 15ppm.

Why is Simultaneous Injection of Fuel Oil and Starting Air into a Main Engine Cylinder Undesirable and How is it Prevented?

Why is Simultaneous Injection of Fuel Oil and Starting Air into a Main Engine Cylinder Undesirable and How is it Prevented?

Simultaneous Injection of Fuel and Starting Air into a Cylinder is Undesirable as it could lead to an Explosion in the Start Air System. 
It is prevented by means of Interlock, which prevents Fuel being Injected when the Air Start Auto Valve is Open. 

The Interlock Operates a Stop Solenoid, which keeps the Fuel Rack at Zero Position. 

What are the Safety Devices fitted to an Air Compressor?

What are the Safety Devices fitted to an Air Compressor?

Low Lub Oil Pressure Shut Down
High Air Temperature Shut Down
1st Stage Relief Valve
2nd Stage Relief Valve
A Fusible Plug is fitted after the 2nd Stage Cooler, Set at 120°C

If Water Cooled, a Jacket Water Safety Valve is fitted.

What is the Primary Function of the Expansion Valve in a Refrigeration System?

What is the Primary Function of the Expansion Valve in a Refrigeration System?

The Primary Function of an Expansion Valve in a Refrigeration System is to regulate the Flow of Refrigerant from the H P side to the L P side of the System. 

The pressure drop causes the Saturation Temperature to drop, enabling it to boil off at the Low Temperature of the Evaporator.

Cloverleafing-

Cloverleafing-
When the cyl l.o. has inadequate acid neutralising properties for the fuel being burnt or if there is insufficient quantity of oil injected then cloveleafing can occur
This is basically regions of corrosive wear midway between the quills and upwards towards the top of the liner. These areas may be visible due to the corrosive effect and they are cloverleaf shaped.
 Eventually the rings become unsupported in these areas, gas builds up on the front face and the ring is subject to collapse.

Emma Mersk

The Most Powerful Diesel Engine in the world-1.jpg

The Most Powerful Diesel Engine in the world-2.jpg



The Most Powerful Diesel Engine in the world-6.jpg


The Most Powerful Diesel Engine in the world-10.jpg


The Most Powerful Diesel Engine in the world-13.jpg