Skip to main content

ME-GI injection system

  • Dual fuel operation requires the injection of both pilot fuel and gas fuel into the combustion chamber. Different types of valves are used for this purpose.
  • wo are fitted for gas injection and two for pilot fuel. 
The auxiliary medium required for both fuel and gas operation is as follows:
  1. High-pressure gas supply.
  2. Fuel oil supply (pilot oil).
  3. Control oil supply for actuation of gas injection valves.
  4. Sealing oil supply. 
  • The gas injection valve design complies with traditional design principles of the compact design. Gas is admitted to the gas injection valve through bores in the cylinder cover. 
  • To prevent a gas leakage between the cylinder cover/gas injection valve and the valve housing/ spindle guide, sealing rings made of temperature and gas resistant material have been installed.
  • Any gas leakage through the gas sealing rings will be led through bores in the gas injection valve to the space between the inner and the outer shield pipe of the double-wall gas piping system. This leakage will be detected by HC sensors.
  • The gas acts continuously on the valve spindle at a max. pressure of about250 bar. To prevent gas from entering the control oil actuation system via the clearance around the spindle, the spindle is sealed by sealing oil at a pressure higher than the gas pressure (25-50 bar higher). 
  • The pilot oil valve is a standard ME fuel oil valve without any changes, except for the nozzle. The fuel oil pressure is constantly monitored by the GI safety system in order to detect any malfunctioning of the valve. The oil valve design allows operation solely on fuel oil up to MCR.
  • The gas engine can be run on fuel oil at 100% load at any time, without stopping the engine. For prolonged operation on fuel oil, it is recommended to change the nozzles and gain an increase in efficiency of around 1% when running at full engine load. 
  • ME-GI injection system consists of two fuel oil valves, two fuel gas valves, ELGI for opening and closing of the fuel gas valves and a FIVA (fuel injection valve actuator) valve to control - via the fuel oil valve – the injected fuel oil profile. Furthermore, it consists of the conventional fuel oil pressure booster, which supplies pilot oil in the dual fuel operation mode.
  • The fuel oil pressure booster is equipped with a pressure sensor to measure the pilot oil on the high pressure side. As mentioned earlier, this sensor monitors the functioning of the fuel oil valve. If any deviation from a normal injection is found, the GI safety system will not allow opening for the control oil via the ELGI valve. In this event no gas injection will take place.

Labels:

Comments

Post a Comment

If you have any doubts.Please let me know

Popular posts from this blog

Differences between MC/MC-C and ME/ME-C engines

The electrohydraulic control mechanisms of the ME engine replace the following components of the conventional MC engine: Chain drive for camshaft Camshaft with fuel cams, exhaust cams and indicator cams Fuel pump actuating gear, including roller guides and reversing mechanism Conventional fuel pressure booster and VIT system Exhaust valve actuating gear and roller guides Engine driven starting air distributor Electronic governor with actuator Regulating shaft Engine side control console Mechanical cylinder lubricators. The Engine Control System of the ME engine comprises: Control units Hydraulic power supply unit Hydraulic cylinder units, including: Electronically controlled fuel injection, and Electronically controlled exhaust valve activation Electronically controlled starting air valves Electronically controlled auxiliary blowers Integrated electronic governor functions Tacho system Electronically controlled Alpha lubricators
9 comments
Read more

Main engine interlocks

Interlocks are provided so that the engine can be started or reversed only when certain conditions have been fulfilled. When there is a remote control of engines, it is essential to have interlocks. This reduces the possibility of engine damage and any hazards to the operating personnel. Turning gear Interlock . This device prevents the engine from being started if the Turning gear is engaged. Running Direction Interlock . This prevents the fuel from being supplied if the running direction of the engine does not match the Telegraph. Starting Air Distributor in end position . This prevents starting from taking place if the shifting of the Distributor has not been completed. Main Lube. oil pressure, Piston cooling pressure, Jacket water pressure, and important parameters must be above the required minimum. Auxiliary Blower Interlock . The Auxiliary Blower is provided in case of Constant pressure turbo charging. Air Spring pressure Interlock . In case of the present generation...
7 comments
Read more

Why is a man hole door elliptical in shape?

Any opening in a pressure vessel is kept to a minimum and for a man entry an elliptical hole  is lesser in size than the corresponding circular hole. More over it is prime concern to have a  smoothed generous radius at the corners to eliminate stress concentration. Hence other  geometrical shapes like rectangle and square are ruled out.  To compensate for the loss of material in the shell due to opening, a doubler ring has to be  provided around the opening. The thickness of the ring depends on the axis length along the  dirrection in which the stresses are maximum and the thickness of the shell. It is important to  align the minor axis along the length of the vessel, as the stress in this direction is  maximum. Longitudinal stress: Pd/2t where P= pressure inside the vessel, d= diameter of the arc, t=  thickness of the shell plating  Circumferential stress: Pd/4t  More over a considerable material and weight saving is achieved as...
20 comments
Read more