Showing posts with label TURBINE. Show all posts
REASON OF TURBOCHARGER DAMAGE
Diesel Engine Exhaust Turbocharger Failure
Turbochargers are among the foremost technologically advanced engine element aboard ship. impeller blades of a medium sized turbocharger often rotate at the maximum amount as 400 revolutions per second. The outer edges of the rotor blades therefore move at 1.5 times the speed of sound.
In the method, the turbocharger digests contaminated exhaust gases of up to 700 degrees centigrade. Thus, the turbocharger may be a terribly sensitive piece of high-speed machinery incessantly serving in harsh conditions and underneath extreme strain. Being on the receiving end of gas flows, turbocharger damages are typically caused by the failure of varied upstream elements.
Turbochargers are among the foremost technologically advanced engine element aboard ship. impeller blades of a medium sized turbocharger often rotate at the maximum amount as 400 revolutions per second. The outer edges of the rotor blades therefore move at 1.5 times the speed of sound.
In the method, the turbocharger digests contaminated exhaust gases of up to 700 degrees centigrade. Thus, the turbocharger may be a terribly sensitive piece of high-speed machinery incessantly serving in harsh conditions and underneath extreme strain. Being on the receiving end of gas flows, turbocharger damages are typically caused by the failure of varied upstream elements.
(1) Diesel engine inlet pressure to reduce main reasons:
(a) the compressor of the filter contamination.
(b) the impeller and vanes diffuser contamination.
(c) the supercharger turbo memory have more carbon deposit, spin resistance increase.
(d) the inter-cooler contamination, increased intake resistance.
(e) turbine exhaust not clear, this is because the pipe blockage, deformation caused by rotor speed rise is not high.
(f)supercharger outlet pressure drop suddenly, it is because of bearing damage caused by.
(2) Compressor surge main reasons:
(a) diesel engine emergency cut-off or sudden unloading (urgent throttle back).
(b) the atmospheric temperature changes cause surge. In the summer of the supercharger with test, in winter could happen surge, this is because the temperature change make working point change and cause.
(c) compressor contamination, especially vanes diffuser contamination.
(d) a engine plant 2 sets of supercharger, Shared a piece of inlet manifold, when a cylinder does not work, can lead compressor surge.
(3) Diesel engine inlet pressure is too high. Generally speaking, the inlet pressure is too high in the supercharger itself is not the problem, but by the engine of the cause, the main reasons are:
(a) the vent valve leakage.
(b) because of engine fuel injection timing inappropriate or other causes for combustion period is too long, to drive a turbine heat increase, speed up, inlet pressure increase.
(4) Produce continuous abnormal sound: this kind of failure is due to the majority of rotor and shell as a result of the collision. Due to the rotor and shell assembly clearance is small, if installation misadjustment or bearing serious damage, then hitting.
(5) The lubricating oil temperature is too high (above 105 ℃) of the main reasons:
(a) the turbine oil, gas seal damage, high temperature gas into the oil chamber.
(b) the bearing damage.
(6) Oil leakage: compressor seal close to the edge of the impeller is low pressure area, easy to produce the oil leakage fault. Main reasons are:
(a) the lubricating oil return not free. The reason has return line congestion, return line sectional area is too small, pipe joint gasket inner hole diameter less than return line; Diesel engine in the crankcase oil level higher than standard, cause oil return difficult; Diesel engine crankcase ventilation blocking or cylinder seal bad, gas expell, make the crankcase internal pressure rise.
(b) the compressor end O ring damage or material ageing and lose sealing effect.
(c) turbocharger oil inlet pressure is too high. Normal pressure is 0.25 ~ 0400000 mpa, if pressure is higher than 0.6 million mpa, from exhaust muffler nozzle will find from the supercharger turbo end leakage oil.
(d) ring not installed correctly or damage.
Tag :
TURBINE,
TURBOCHARGER
CARGO OIL PUMP TURBINE OPERATING INSTRUCTIONS
STARTING
1.
Check all the turbine lubricating oil sumps for water
using the sump
drain valve and drain as necessary.
2.
Top up the oils to slightly above the working level.
3.
Check and replenish the governor oil levels.
4.
Open the cargo oil pump turbine vacuum condenser inlet
and outlet SW
valves.
5.
Check that the seawater overboard valve is full open.
6.
Open the vacuum condenser cooling seawater pump
suction and
discharge valves.
7.
Start the vacuum cooling seawater pump. Vent any air
from the
condensers.
8.
Open the air ejector condenser inlet and outlet
cooling FW valves.
9.
Open all cargo oil pumps lubricating oil cooler inlet
and outlet FW
valves. Cooling water is supplied from the low temperature
cooling
fresh water system.
10. Start the local cargo
oil pump turbine pre-lubricating oil pumps.
11. Check the oil levels in the lubricating oil sumps.
Check that oil pressure
reaches the priming pressure of 0.3kg/cm2
12. Ensure that the trip
cylinders move out and that the trip latch is in a
position to engage.
13. Open the cargo oil
pump turbine exhaust valves.
14. Open the vacuum condenser condensate pump suction and
discharge
valves, balance line valves and the condenser recirculation and level
control valves.
15. Start one condensate pumps and ensure that the hot
well level remains
normal.
16. Prepare and warm through the air ejector steam lines.
17. Open the air ejector condenser drain to the vacuum
condenser valves.
18. Full vacuum will not be achieved until gland steam is
supplied to the
turbines.
19. Open all the turbine drain valves, steam chest drain
valves, individual
steam line drain valves, low point steam trap valves and
drain separator
steam trap drain valves.
20. Slowly and carefully open the cargo oil pump main
steam stop warming
through valve.
21. Warm and drain the steam lines and turbines, closing
in the drains as
necessary.
22. Warm through and supply gland steam to the turbine
gland systems.
23. If inert gas is required prior to the starting of the
cargo pumps open
the inlet and outlet valves to the main steam dump valve and
set the
boiler to IGS top up mode.
24. Put the required COP on worm up mode and it will
rotate at 200 r.p.m.
for set time.
25. Change over the COP control to remote.
STOPPING
1.
Close the cargo oil pump turbine main steam stop valve
and close all
the gland steam valves.
2.
Open all the turbine, line and steam chest drains.
3.
Ensure that all the lubricating oil-priming pumps are
running.
4.
Close the cargo oil pump turbine exhaust valves.
5.
If the vacuum condenser is not required for any other
service shut down
the air ejector(s).
6.
Stop the condensate pump. Leave operational in case
the condenser hot
well level rises due to condensation.
7.
Leave the sea water-cooling operating for at least two
hours.
8.
When the system has cooled down, close the lubricating
oil cooler water
supply valves.
9.
Leave the lubricating pumps running to reduce
corrosion in the turbine
gearing.
10. Shut down the fresh
water-cooling to the air ejector condenser and
seawater cooling to the vacuum condenser.
seawater cooling to the vacuum condenser.
Tag :
CARGO OIL PUMP,
TURBINE