Discover essential insights from the Wartsila 18V50 running data of engines. Get a comprehensive overview of performance and operation.
Wartsila 18V50 Running data
| Description | Parameter |
| Charge Air Temp. in air receiver | 55 ℃ |
| Exhaust Gas Temp. Before TC (A Bank) | 530 ℃ |
| Exhaust Gas Temp. After TC (A Bank) | 335 ℃ |
| Exhaust Gas Temp. (Cylinder) | 480 ℃ |
| Cylinder Liner Temp. | 121 ℃ |
| Lube Oil Temp. Before Engine | 63 ℃ |
| Lube Oil Temp. After TC | 93 ℃ |
| Fuel Oil Temp. | 110 ℃ |
| Main Bearing Temp. | 92 ℃ |
| Big End Bearing Temp. | 80 ℃ |
| Thrust Bearing Temp. | 80 ℃ |
| CA Pressure Engine Inlet | 4.0 bar |
| HT Temp. Engine outlet | 94 ℃ |
| LT Temp. Before Cooler | 50 ℃ |
| LO Pressure TC Inlet | 2.2 bar |
| TC Speed | 17000 rpm |
| Crank case Pressure | 0.5 mbar |
| Torsional Vibration Level | 90 mdeg |
| Active Power | 18415 kW |
| Reactive Power | 12800 KVar |
| Power Factor | .80 |
| Frequency | 50 Hz |
| Engine Speed | 500 rpm |
| Fuel Rack Control | 68% |
| Mixing Tank Pressure | 4.5 bar |
| Fuel Pressure Engine Inlet | 7-9 bar |
| FO Flow rate | 3600 kg/hr |
| FO Viscosity Engine Inlet | 20 cst |
| Generator Winding Temp. | 100 ℃ |
| Generator Bearing Temp. | 80 ℃ |
| LO Pressure Engine Inlet | 4.1 bar |
| HT water pressure | 3.7 bar |
| LT water pressure | 2.5 bar |
| Radiator Speed | 55 % |
ENGINE SPEED
- Measured by camshaft wheel or flywheel.
- Unstably, engine speed can be caused by wrong governor settings worn/jamming regulating mechanism.
- Alarm/safety blockings.
- Safety functions: over speed.
TURBO CHARGER SPEED
- This is an important factor to follow since the turbo speed gives an indication when the nozzle ring gets dirty. I.e. the turbo speed increases slightly.
FUEL RACK POSITION
- Indicates the amount of sprayed fuel oil (engine load).
- Increased fuel rack index (same load) can be the result of the worn pump (bigger internal leakages), a change in fuel quality, or a lower heat value.
IGNITION QUALITY PARAMETERS
- Energy
- Viscosity
- Maximum firing pressure.
- Injection delay
- Ignition delay
ENERGY COMPARISON
- The injection pump is a volumetric pump.
- The higher the density, the more energy it contains per volume unit.
- The density difference between HFO and MDO is larger than the difference in net calorific value.
VISCOSITY COMPARISON
- The viscosity of MDO is lower than the viscosity of HFO (even HFO is heated)
- Lower viscosity fuels result in more internal leakage in the injection pump from the high-pressure side to the low-pressure side.
- Internal leakage has to be compensated by giving more fuel racks.
MAXIMUM FIRING PRESSURE
- Depending on the charge, air pressure
- To achieve proper combustion, the firing pressure has to be high and thus also the charge air pressure.
- Timing of the fuel pump
- INJECTION DELAY is the time it takes to build up a pressure higher than the opening pressure of the nozzle
- The delay is comparable to the condition of injection equipment
- IGNITION DELAY is the time gap between the commencement of injection and the commencement of ignition.
- Depending on the fuel quality
- Compression temperature has a big influence on the ignition delay
- Compression temperature is not high enough for the fuel to ignite longer ignition delay
HIGHER PEAK PRESSURES AND HIGHER EXHAUST GAS TEMPERATURES
- Normally, 1…2 ° of crank angle.
- Too early timing of injection
- Higher peak pressure
EXHAUST GAS TEMPERATURE AFTER CYLINDER
- Measured individually after each cylinder
- Each cylinder has two measuring points.
- The average temperature of all exhaust temperature sensors is approximately 100 °C lower than the exhaust gas temperature before the turbine.
- Maximum allowed difference between valves in one cylinder.
- Maximum allowed difference of one cylinder average from the average of all cylinders, alarm.
- In normal operation, the average temperature Cylinder temperature deviation can be up to 30 – 40 °C.
- The engine is (depending on installation) provided with a safety slow-down arrangement if the temperature difference is too big.
- A 10 °C increase in ambient temperature will result in approximately 15 °C increase in exhaust gas temperature.
EXHAUST GAS TEMPERATURE AFTER TURBOCHARGER
- Indicates the kinetic energy of the exhaust gases that are running the turbine
- Indicates the condition of the turbo, i.e. scavenging of the engine
- If a de-Nox catalysator is installed, the temperature has to exceed a certain level to ensure the function of the catalysator.
PRESSURE DIFFERENCE OVER THE CYLINDERS:
- Measuring the pressure difference between the charge air manifold and the exhaust gas manifold. Indicates how well the scavenging works.
- Depends on the turbocharger. Therefore, the values below should be considered as allusive.
- The bigger the DP is, the better the scavenging.
- The normal value with a 100% load varies depending on installation. Once the value has been dropped down, it is an indication that something is wrong with the engine -e.g. dirty nozzle ring & turbine.
DIRTY CHARGE AIR COOLER:
- As indicated by the increase of the pressure difference over the cooler, remember that the dirtiness of the cooler aggravates the cleaning of the cooler.
CONSEQUENCES:
- Less fresh air to cylinders
- Higher exhaust gas temperatures
- Improper combustion
- Low peak pressures
- More deposits to the nozzle ring
- Increased SFOC
- Increased SLOC
- Higher fuel rack reading at the same load
CONDENSE WATER IN CHARGE AIR:
- Condense water that is condensing in the cooler has to be drained out
- Causes wear in the pistons, piston rings and cylinder heads
- Will cause inlet seat ring problems
- The amount of condensed water may be reduced by increasing the charge
- Air temperature, but the maximum temp must not be exceeded, which is 55 ° C
- Increases thermal loading of the engine
DIRTY NOZZLE RING:
- Indicated by;
- Slightly higher turbine speed
- Higher receiver temperature
- Decreased pressure difference over the cylinders
POSSIBLE CONSEQUENCES
- Remainder pressure in the cylinders increase
- less fresh air to cylinders
- worse scavenging
- delayed combustion
- more deposit accumulations
- higher exhaust gas temperatures
- increased thermal load
- increased risk of engine failure
- piston seizure
- hot corrosion
- increased fuel consumption.
LOW PEAK PRESSURES-HIGH EXHAUST GAS TEMPERATURES:
- Obvious reason:
- DELAYED COMBUSTION
- Dirty air cooler
- dirty nozzle ring(s)
- injection nozzles in bad condition
- worn injection pumps
- a long injection delay
- bad fuel
- high CCAI value, poor ignition properties
- high water content
- high exhaust gas temp
HIGH EXHAUST GAS TEMPERATURES
- Injection valves in bad condition
- dirty nozzle ring
- dirty air cooler
- Low fuel viscosity
- worn injection pumps
- bad fuel
- burned valves or seats
HIGH FUEL RACK READING COMPARED TO LOAD
- Worn injection pumps
- more internal leakage
- too low viscosity of the fuel
- more internal leakage
- low heat value of the fuel
- high water content
- dirty fuel filter
- too low fuel pressure
- big fuel leakage
