Power Nozzles are stationary vanes located in the hot gas path of the turbine. They are responsible for generating thrust by rotating and accelerating the gas flow in the downstream blade rows.
These components are subjected to high stress and extreme oxidation due to operating conditions, causing cracks in the base material and creep deflection. Based on the damage volume, a medium or heavy scope of work is determined during the inspection process.
Usually, severely cracked and oxidised zones require weld repair. The number of welded areas will determine the scope of work as medium or heavy.
Most cracks, detected during red dye penetrant testing can be repaired by TIG welding. Due to the special geometry of the parts, welding and machining require exceptional attention and expertise.