Ship's Main Engine Performance Test | Chief MAKOi

Summary

This video explains how ships measure the performance of their main engines, from traditional mechanical tools to modern automated systems. It covers the measurement process, including setting engine speed, taking pressure readings, and calculating power output. The video demonstrates the use of advanced transducers and computer systems to monitor engine performance, generating PT and PV diagrams to assess compression and combustion pressures. A detailed example calculation illustrates how engine power is determined. The process ensures engines run efficiently and helps with troubleshooting, ultimately optimizing performance during voyages.

Takeaways

• 😀 Regular performance checks of the main engine are crucial for ensuring optimal working conditions on board ships.
• 😀 Performance tests can also help with troubleshooting engine issues.
• 😀 In the past, mechanical indicator tools were used to measure engine performance, but modern automatic monitoring systems provide faster, more accurate measurements.
• 😀 Main engine performance is only measured during transit, in calm seas, and with good weather conditions, typically once a month.
• 😀 Proper coordination with the bridge is essential to avoid engine turns or course changes during measurement.
• 😀 Engine speed is set to 85% of the maximum continuous rating (MCR) to begin the performance measurement process.
• 😀 Fuel oil, cylinder lube oil flow meters, and lube oil leakage are important parameters to monitor alongside engine speed.
• 😀 Modern indicator tools use transducers and computers instead of mechanical components for measuring engine performance.
• 😀 The transducer is mounted on the indicator valve to measure cylinder pressures, both from compression and combustion.
• 😀 The results of each measurement are automatically recorded and displayed on the computer, showing diagrams like the PT and PV diagrams.
• 😀 The PT diagram shows the compression pressure and maximum pressure of each cylinder, while the PV diagram displays pressure variations during the cylinder cycle.
• 😀 Indicated power is calculated using formulas that incorporate pressure, stroke length, cylinder area, and the number of power strokes per second, leading to power output values like kilowatts or horsepower.

Q & A

Why is it important to regularly check the performance of the main engine on ships?

Regular checks are essential to ensure the main engine operates optimally, which helps prevent breakdowns and allows for troubleshooting if issues arise.

How was engine performance measured in the past, and how has technology improved this process?

In the past, engine performance was measured using mechanical indicator tools. However, technological advancements have led to the use of automatic monitoring systems, which are faster, easier, and more accurate.

When are the main engine performance measurements typically conducted?

Measurements are typically conducted while the ship is transiting in calm seas and good weather, usually once a month.

What is the required engine speed for conducting performance tests?

The engine speed should be set to 85% of the Maximum Continuous Rating (MCR), which for this engine is 81 revolutions per minute (RPM).

What additional measurements are necessary during the performance test, aside from engine speed?

In addition to engine speed, readings for fuel oil, cylinder lube oil flow meters, and the rate of lube oil leakage in the piston rod stuffing box are also necessary.

How does the modern measurement tool differ from the old mechanical indicator tool?

The modern tool uses a transducer, a calibration box, and a computer, whereas the old tool used mechanical springs, a stylus, and magnetic paper.

How is the transducer connected to the engine during the performance test?

The transducer is mounted on the indicator valve, which taps into the cylinder to measure pressure from both compression and combustion.

What is the PT diagram, and what does it measure?

The PT (Pressure-Time) diagram displays the pressure changes within the cylinder during the engine cycle. It helps measure the cylinder's compression pressure (P-comp) and maximum pressure (P-max).

What does the PV diagram represent, and how is it used in performance testing?

The PV (Pressure-Volume) diagram shows the variation of pressure within the cylinder during a complete cycle. It is used to measure the indicated pressure in the cylinder, which helps in calculating the engine's indicated power.

How is the indicated power of the engine calculated?

Indicated power is calculated by multiplying the indicated pressure, the cylinder's stroke length, the cylinder bore area, and the number of power strokes per second.

Can you give an example of how the engine's power output is calculated from the measurements?

For example, using an average indicated pressure of 12.3 bar, a stroke length of 2.4 meters, and a bore of 0.6 meters, the engine's power output is calculated to be 1127 kilowatts per cylinder, resulting in a total output of 6762 kilowatts or 9068 horsepower for six cylinders.