There are several different factors that affect the intervals for gas turbine maintenance. These factors include the operation of the turbine – the starts, base load, trips and peak load, the air quality of the air used on the turbine, the fuels used and the method used to control NOx.
Operation of the Turbine – There are several factors here. If you are at peak load, the life of your blades will experience an effect greater than 6 fold when compared to when you are at base load. In addition, when you are at full load, this is the same as eight normal starts when it comes to cycle life consumption.
Fuel – if you use refined distillates or natural gas, then you will have to deal with less radiant heat than if you are using a heavy hydrocarbon fuel. Hydrocarbon fuel’s heat tends to reduce the life of your combustion components. Additionally, heavy oils also have corrosive elements in them, such as vanadium, sodium, lead and potassium. These in turn quickly corrode the blades and nozzles of the turbine, which makes your gas turbine maintenance intervals even shorter. Natural gas tends to reduce problems related with corrosion.
Water or Steam Injection – If you are using fuels that are not natural gas, then you will need to inject water or steam in order to control NOx. This then increases the temperature that is experienced by the blades and nozzles.
Quality of air – If the air has particles of oil, salt or dust, they can be a source of erosion, compressor fouling and corrosion. To reduce these effects, you need to employ filtration. The manufacturer will often recommend the best filter depending on where the turbine is located. It is therefore important to ensure that the filter is cleaned and replaced as needed based on the pressure drop readings.
Inspection – The manufacturer will provide you with an inspection schedule that is intended to let you know how the components are faring. Based on the results of the inspection, you will carry our replacements and repairs in order to ensure the continuation of safe operations. The inspections usually include:
- Inspection of the combustor
- Major inspection
- Inspection of the hot gas component
These intervals tend to be pretty much the same across the board as follows:
- Have a combuster inspection done on a 8,000 operating hours
- Check your hot gas path at 24,000 operating hours
- At 48,000 to about 50,000 operating hours, have a major inspection carried out
Now that you know the factors that are affecting your Gas Turbine Maintenance intervals, make sure you book your next maintenance with us. Let the experts handle your very business.