MEOclassIIexamnotes

Scuffing is a form of micro-seizure of Piston Ring when LO breaks down.  Scuffing is caused due to;  Bad Cylinder Lubricant  Defective Cyl. Lubricator  Insufficient LO Points  No oil groove in liner  Absence or wrong Scraper Rings.

» When it is necessary to cut-off T/C due to heavy vibration, bearing failure, etc. cutting  procedure should be done as per engine maker’s instruction.  » Cutting-off operation depends on number of T/C installed and number of T/C damaged.  Following procedures are in accordance with Sulzer RT engine practice:  Case I: Failure of one T/C, with Exhaust by-pass piping: Lock rotor as per T/C manual.  Remove blank flange in by-pass exhaust piping. Open covers of scavenge air trunk.  Auxiliary blowers must be running during operation.  If casing is cracked, stop T/C cooling.  If T/C is supplied with external lubrication, shut L.O. supply.   Output 25%: RPM 60% at MCR.  Case II: Failure of one T/C, of two T/C engine: Lock rotor of damaged T/C.  Remove expansion joints of both exhaust inlet and air outlet of damaged T/C,  and put blank flanges.  If casing is cracked, stop T/C cooling.  If T/C is supplied with external l...

1. Gas freeing is essential before entering empty tank.  2. Manhole doors to be opened for at least 24 hours before entry.  3. Forced ventilation with air duct, to be done with electric blower, for at least 24 hours.  4. With forced exhausting system, minimum of 2 air changes should be completed during  that time. [For every dangerous space, 10 to 20 air changes are necessary.]  5. After thorough ventilation, tank atmosphere tested for any toxic or explosive gases, by  invited Chemist or with Safety Lamp before entering. [Flame will burn clearly, if free  from foul gases. Faint blue cap will show presence of explosive gases. If burning black  or flame goes out, it shows presence of CO₂ gas, which is fatal to life].   When tested by Chemist, TLV must be taken as a standard.  6. When the tank is gas free, following LSA to be carried or kept ready, when entering.  a) Lifeline or harness to be put on.  b) Spark proof hand torc...

An IC engine of over 200-mm bore or crankcase volume of 0.6 m³ and above,  shall be provided with crankcase relief door with sufficient relief area.(Regulation)  Opening pressure = 1/15 bar (0.07 bar) above Atmospheric pressure, but ≯ 3∼7  bar of explosion pressure.  Free area of each relief valve ≮ 45 cm².  Combined area of relief valves ≮ 115 cm² per m³ of crankcase volume.