Download TURBINE ENGINE REMOVAL AND OVERHAUL

TURBINE ENGINE
REMOVAL AND
OVERHAUL
Checking Turbine Blade
Tip-to-Shroud Clearance
Blending
(not margaritas)
• Blending- A method of filing compressor or turbine
blades and vanes to remove damage and reestablish the
appropriate contour for an aerodynamic shape
• Blistering- Raised areas that indicate a separation of a
surface layer from a base metal, often evident as peeling
and/or flaking of a metal plating
• Bow- A stress-induced bend or curve in a blade’s or
vane’s contour
• Bulge- An outward bending or swelling caused by
excessive pressure of weakening due to excessive heat
Defect /Repair Terminology
Checking A Nozzle Vane
for Bowing
But not Boeing, they manufacture aircraft not engines!
• Compression- A squeezing force produced by two
opposing forces acting on a part.
• Creep(growth)- A condition of permanent elongation in
rotating airfoils resulting from thermal stress and
centrifugal loading.
• Primary- blue, red, or yellow
• Secondary- purple, orange, or green
• Tertiary-aquamarine, mauve….
• Dynamic Balancing- balancing along rotational plane
and the rotor axis
• Electrolytic Action(galvanic corrosion)- a breakdown
of surfaces caused by electrical activity between
dissimilar metals
Defect /Repair Terminology Continued
Compressor Blade
Defects
• Flowing- The spreading out of a plated or painted surface
caused by poor adhesion to the base or excessive loading
on the part’s surface
• Galling- fretting or chafing of a mating surface by sliding
contact with another surface-metal is transferred from one
surface to the other
• Glazing- development of hard, glossy surfaces in the
presence of oil, heat, and pressure
• Guttering- deep concentrated erosion that results from an
enlargement of cracks or repeated exposure to a
concentrated flame
• Profile- the contour or aerodynamic shape of a blade or
surface
Defect /Repair Terminology Continued
Typical Repair Limits
• Shear- a tearing force produced by two opposing
parallel forces acting on a part
• Static Balancing- a procedure that balances the
main rotating assembly of a turbine engine to
reduce vibration
• Tension- A force that tends to pull an object apart
• Untwist- a straightening and loss of blade
curvature that results from gas loads, thermal
stress, and centrifugal loading
Defect /Repair Terminology Continued