Procedure for Boiler blow down

Precautions

1.     Ensure nobody is near the ship side blow down valve.

2.     Not to be carried out in drydock or alongside.

3.     Valve sequence to be followed.

4.     Boiler shouldn’t be left unattended during blow down.

5.     Monitor the end of blow down. Long blow down to be avoided.

6.     Don’t blow down to the E/room bilges.

Procedure

1.    Ship side valve 1 is opened followed by valve 2.

2.    Valve 2 is NR which is fully opened to avoid cutting off seat.

3.     Rate of blow down controlled by Valve 3.

4.     For scum blow down valve 4 & 5 are used.

1. During maneuvering Bursting disc of air compressor get damaged, what action to take?

1.     Inform the bridge about the problem and to give lesser kicks.

2.     Start the stand by compressor.

3.     Isolate the compressor whose bursting disc is damaged.

4.     Change the bursting disc, if available onboard.

5.     If Not available, then let the S.W go into the E/room bilges, otherwise Fresh water cooled , then join a flexible hose and put into the expansion tank.

What all clearances taken in centrifugal pump?

1.     The wear ring & impeller.

2.     The wear ring & the casing.

3.     Shaft and the bush.

How Alkalinity test of boiler water is carried out?

1.     Take 200 ml water sample in the stoppered bottle.

2.     Add one P.Alkalinity tablet & shake or crush to disintegrate.

3.     If P.Alkalinity is present the sample will turn blue.

4.     Repeat the tablet addition, one at a time, until the blue colour turns to permanent yellow.

5.     Count the number of tablets used and carry out the calculation:

P.Alkalinity, ppm CaCO3 = (Number of tablet x 20) -10

f. Record the result obtainied on the log sheet provided, against the date on which result was obtained.

Overhauling procedure of Diesel engine fuel valve.

Safety Precautions:-

a. Check whether all tools and spares are available or not.

b. If so, then start the Stand by generator.

c. Check all parameters are normal.

d. Now share the load with the help of synchroscope.

e. Again check all the parameters are within normal range.

f. Put full load on the Stand by generator.

g. Stop the generator on which work has to be carried out.

h. Put MEN AT WORK tag.

i. Shut the air starting valve, fuel oil inlet & outlet valves and isolate the system.

j. Let lube oil priming pump run for half hour after then stop it.

k. Remove the lock nut of the high pressure pipe.

l. Now, remove the high pressure pipe.

m. Take out the fuel injector using it tool.

n. Put it on the testing kit.

o. Check the lifting pressure, atomization, pressure falling steadily, dripping of oil.

p. Now, take out the injector from the testing kit, put in a diesel oil & clean it.

q. Make sure the workshop table should be clean, no rags or jute to be there.

r. Put the injector on the vice and tighten it.

s. Loosen the lock nut of the injector.

t. Now loosen the compression nut to release the spring pressure, then take out the spring.

u. Open the cap nut and take out the needle and guide.

v. Put the parts on the cleaned table.

w. Check the condition of spring by dropping on the floor plate, it should jump and also check it by tightening in the vice and then releasing. The difference in the length,no cracks to be there.

x. Check visually needle, there shouldn’t be any scoring marks because it is made of Nitrite material.

y. Try to insert the needle inside the guide at angle of 45degree, the needle should on its own weight.

z. Check the size of injecting holes by using Go or No go gauge.

i. If go gauge is going then hole size is OK.

ii. If no go gauge going, then it means the size has increased, then nozzle needs to be changed.

iii. Now assemble the injector and do the lifting pressure setting on test kit by adjusting the compression nut.

iv. After this check the injector again for its lifting pressure, atomization, steady fall of pressure and dripping.

Reasons for Boiler Blow back and actions in case of blow back.

Reasons:-

1.     Insufficient pre-purging.

2.     Blower not working.

3.     Accumulation of oil.

4.     Leaky solenoid valve.

5.     Dripping of burner.

Action:-

1.     Stop the firing.

2.     Check the condition of burner, if it is dripping, then overhaul is required.

3.     Do the inspection of the furnace.

4.     Carry out sufficient pre-purging.

5.     Start the boiler on “Auto” mode.

Checks to be carried out during normal running of Auxiliary / generator engine

Checks:

1.     Check scavenge air temperature.

2.     Check Exhaust gas temperature.

3.     Check r.p.m

4.     Check load on A/E.

5.     Carry out peak pressure.

6.     Check for any abnormal noise or vibration.

7.     Check jacket water inlet & outlet temperature.

8.     Check Lube oil temperature & pressure.

What to do if domestic fridge is short cycling?

- L.P Cut out is defective.

- L.P Cut out setting not correct, too low difficult for Cut In.

- Lesser gas flow

1.     Less gas in system.

2.     Drier Choked.

3.     Expansion valve filter choked or Expansion valve Malfunction.

4.     Evaporator Choked.

5.     Compressor valves leaking.

Actions:-

a. Check L.P. Cut out setting, Cut out pressure OK.

b. Check flow of gas by seeing sight glass which should show full flow of refrigerant.

c. If no full flow- Either less gas or drier chocked, Clean the drier.

d. Check level in receiver, if low, then charge gas.

e. Expansion valve filter choked, then clean it.

f. Expansion valve malfunctioning- Change it.

g. Evaporator choked- Blow-thru evaporator with nitrogen.

Actions in case of lot of smoke coming out of funnel

1.     Reduce load on engine.

2.     Check purifier operating alright/ reduce throughput to have better purification.

3.     Drain water from settling & service tank.

4.     Check scavenge air temperature & adjust if reqd. .

5.     Soot blow the economizer.

6.     Ensure, fuel oil end heater outlet temperature proper corresponding to attain viscosity at the point of injection.

7.     Check, if any particular Exhaust temperature is higher than others, if so, then stop the engine, Change the injector with a spare overhauled injector.

8.     Check all fuel pump timings are correct or not.

9.     Dismantle and carry out overhaul of T/C.

10.   Send fuel oil for Laboratory analysis.

Reasons:

1.     Improper combustion.

2.     Burning of carbon particles collected at EGE.

3.     Overloading of engine.

4.     Inform bridge & Chief engineer.

5.     Raise engineers’ call/emergency alarm.

6.     Before starting bilge pump note down the position of vessel & time of starting.

7.     Other engineers will in between try to locate the hole or burst of pipe and repair.

8.     If ingress of water very high, start another pump.

9.     Reduce the engine r.p.m.

10.   Change over main s.w suction to emergency bilge suction.

11.   If level is still coming up try to protect the motor from short-circuiting , if required start emergency bilge suction valve.

12.   If situation is not coming in control, prepare lifeboat for lowering.

What is Air Compressor Bumbing clearance? How to Check and adjust it?

1.     Start the Stand by compressor.

2.     Stop the compressor whose bumping clearance has to be taken.

3.     Isolate the system.

4.     Put “Men at Work” tag.

5.     Loosen the cylinder head bolts and lift it.

6.     Measure the diameter /size of the lead ball.

7.     Bring piston to TDC and put lead ball on centre of it.

8.     Now, put the cylinder head and tighten it to required torque.

9.     Now, again loosen the cylinder head bolt and remove the ball.

10.   Measure the size of the ball.

11.  The difference between the initial size and final size is the bumping clearance.

It can be adjusted by either putting a thinner gasket or putting shim on top half