Assessing Gas Turbine LM2500 Technology

The LM2500 is considered as the most versatile engine as it has been uprated as well as improved several times since its commercial inception. This gas turbine can be found in utility/IPP peaking, combined cycle plants and cogeneration as well as in trailer mounted emergency/standby packages, mechanical drive applications, drilling platform service, marine main propulsion systems and industrial combined heat and power.

Gas Turbine lm2500 - Engineering gas turbine

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Gas fuel control and regulating valves were found to be the leading cause of forced outages in over LM2500 engines within the electric generation service. Communication/controllers/control issues were second on the top ten list of forced outage causes. An assessment of the turbine for peaking machines over a five year period revealed the following:

  • An improved forced outage factor of 0.4% in 2013 that was far much better than the annual 4.28% average between 2009 and 2013.
  • Fleet availability averaging 95.3% annually
  • Maintenance outage factor of 0% in 2013 with a five year average of 0.6%
  • Planned outage factor of 3.4% in 2013 that was a point above annual average for the period
  • Service factor of 2.3% in 2013 that is slightly below the annual average of 3%.

In terms of cycling engines, the numbers were as follows:

  • Service factor 24.4% in 2013 that was significantly below the 30.9% average.
  • Planned outage factor 1.8% compared to the five-year average of 2.4%
  • Maintenance outage factor of 0.2% versus an average of 0.9%
  • Forced outage factor of 3.2% in 2013 that was a tenth of a point more than the average
  • Fleet availability of 94.9% in 2013 that is slightly higher than the 93.5% average

Results for base load machines were received well with the 2013 numbers beating annual averages throughout all the categories:

  • Service factor 89.8% versus 87.3%
  • Planned outage factor of 2.1% versus 2.7%
  • Maintenance outage factor of 0.5% versus 0.6%
  • Forced outage factor of 1.1% versus 1.2%
  • Fleet availability 96.3% for 2013 versus 95.6%

Analysis of Forced Outages

An analysis of the LM2500 technology was done by recording and evaluating incidences of forced outages in 2013. A total of 477 incidents were recorded, a number that is higher compared to the previous year. From this assessment, the average time for outages that were caused by gas fuel control and regulating valves was less than five hours.

Of the 53 incidences recorded, 15 were traced to issues relating to metering valves, half were associated with actuator where most of them were reported by a single unit. Out of seven units, eight incidents had to do with failure of the gas valve to shut off while another eight were linked to sticking gas valves. However, six of the incidences reported were at a single site. The other failure incidences were linked to calibration issues, gas valve wiring and pressure fluctuations among other things.

Generally, the longest outage lasted six months due to the repair of the damaged blading at the sixth stage in the US. It is interesting to note that the top ten contributors of the LM2500 forced outage against the fleet accounted for 81% of the total outage hours against the fleet the previous year. Chose AC-DLE to manage your company Gas Turbine LM2500 Technology, because we have completed the following Gas Turbine Control System Retrofit or upgraded the vary of projects.