DMC:V2500-00-70-02-02-00A-006A-D|Issue No:002|Issue Date:2020-02-01

Export Control

EAR Export Classification: Not subject to the EAR per 15 C.F.R. Chapter 1, Part 734.3(b)(3), except for the following Service Bulletins which are currently published as EAR Export Classification 9E991: SBE70-0992, SBE72-0483, SBE72-0580, SBE72-0588, SBE72-0640, SBE73-0209, SBE80-0024 and SBE80-0025.

Copyright

© IAE International Aero Engines AG (2001, 2014 - 2021) The information contained in this document is the property of © IAE International Aero Engines AG and may not be copied or used for any purpose other than that for which it is supplied without the express written authority of © IAE International Aero Engines AG. (This does not preclude use by engine and aircraft operators for normal instructional, maintenance or overhaul purposes.).

Applicability

All

Common Information

TASK 70-02-02-350-501 Specified Types Of Damage

General

This TASK gives names to specified types of damage. This is to prevent errors which can occur when different names are used for the same type of damage. Always use the correct name for the specified type of damage or condition when an inspection is made on a component.

The definition of damages contained in this section does not include the Ball and Roller Bearings. For Ball and Roller Bearing Inspection/Description of Damages refer to TASK 70-29-01-290-501.

Preliminary Requirements

Pre-Conditions

NONE

Support Equipment

NONE

Consumables, Materials and Expendables

NONE

Spares

NONE

Safety Requirements

NONE

Procedure

SUBTASK 70-02-02-350-001 The Types of Damage to Metal Parts

Refer to Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure, Figure.

TYPE OF DAMAGE	RELATED DATA	RELATED CONDITION
Arced	Flashed-over	The effects that can be seen (burned or fused metal) of an unwanted electrical discharge between two electrical connections
Battered	Damaged by impacts	Is damage caused to a part when it is constantly hit. Refer to Figure
Bent	Creased, folded, kinked, leaning	Is angular change from the initial shape or contour usually the cause is a lateral force. Refer to Figure
Binding	Sticking, tight	Is decreased movement such as a tightened condition which results from very hot or very cold temperatures or an unwanted particle between surfaces
Bowed	-	A curve which changes the surfaces usual shape or contour. Usually the cause is heat or a lateral force. Refer to Figure
Brinelled	-	Circular surface damage on bearing races. Usually the cause is constant shock loads given to the bearing. Refer to Figure
		False Brinelling
		Roller bearings: It is seen as axial lines across the roller track which are surface blemishes. This is permitted.
		Ball bearings: Are two marks related to each ball that can be seen on the ball track which are surface blemishes. This is permitted
Brittle	Perished	A change in the elasticity of the material
Broken	Fractured	The separation of a part by force, into two or more pieces. Refer to Figure
Bulged	Ballooned, swollen	Internal and external local distortion. Usually the cause is too much heat or differences in pressure. Refer to Figure
Burned	Charred	A complete structural failure of the material because of very hot temperatures. Refer to Figure
Burnish	A shiny area resulting from rubbing against a hard, smooth surface; may contain scratches of no apparent depth.
Burrs	-	Rough edges or sharp projections on the surface of a material
Carboned	Carbon covered, carbon tracked, coked	A quantity of carbon particles collected on the surface of a material. Refer to Figure
Chafed	Scraped, scuffed	Friction wear damage, usually the cause is two parts that rub together with a small amount of movement
Checkered	Crazed	Surface cracks; usually the cause is heat
Chipped	-	Material broken off the edge, corner or surface. Usually caused when a material is hit
Collapsed	Crushed	The surface is pulled below its initial contour. Usually the cause is large differences in pressure. Refer to Figure
Corroded	Rusted, oxidation, etched, sulphidation	Slow deterioration of the material because of a chemical effect. Usually seen as oxide particles on the surface
Cracked	-	A linear opening that can easily be seen and which can cause the material to break. (Special fluorescent or magnetic penetrants are not necessary). Refer to Figure
Crossed	-	Material damage to a part, for example, crossed thread. Alternatively a part incorrectly assembled, for example, crossed wires
Curled	-	A rounded fold in the material such as a blade tip that has rubbed against the engine casing. Refer to Figure
Dented	-	Damage to the surface of a part when it is hit with an object. The material is distorted but not removed. Refer to Figure
Deposits	Metalized	Particles of material collected on a part from a different part or material. Refer to Figure
Disengaged	Separated, loose	This occurs only to parts that are usually permanently attached to each other
Disintegrated	Shattered	Completely broken in pieces. Refer to Figure
Distorted	Buckled, depressed twisted, warped	Is damage that changes the initial shape or contour of a material. Usually caused when the material is hit, made hot or has structural stresses applied. Refer to Figure
Eccentric	Non-concentric	Occurs when a part has the point about which it turns moved off center
Eroded	-	The flow of fluids or gases cause the material to wear; heat or grit makes this occur more quickly
Extruded	-	Plastic deformation because of high pressure between parts
Feathered edge	-	The edge of the material is made thinner
Flattened out	-	Permanent damage more than the tolerance limits. Usually caused when the material is compressed
Frayed	-	Worn (rubbed) in to strips
Fretted	-	Damage caused when two materials are rubbed together
Fused	-	When two materials become attached to each other, usually the cause is heat, friction or current flow
Galled	Fretted, spiked	Damage caused when two materials are rubbed together at high pressure. Refer to Figure
Glazed	-	This is seen as a hard glossy surface because of heat, varnish, incorrect loads or when the surface is rubbed
Gouge	-	A large rough cut of large depth with the removal of some material, caused because a sharp object has hit the part. Refer to Figure
Grooved	Furrowed, fluted	A smooth rounded score, because of wear, with rounded corners and smooth on the groove bottom
Imperfection	An interruption (non-uniformity) in the normal surface condition of a part configuration which must be evaluated for acceptance to an assigned standard.
Indications	-	Small cracks or other small defects that can not be seen without fluorescent or magnetic penetrants
Melted	-	Distortion to the initial shape or contour because of heat friction or pressure
Nicked	-	A small cut on the surface or edge of a part caused when the part is hit with an object. Refer to Figure
Overheated	Heat discolored, heated excessively, seen as a change in color or condition. hot spot	The part has become too hot, usually Refer to Figure
Part missing	Lost	Related only to a detail that is usually permanently attached
Peeled	Blistered, flaked, exfoliated	Is when the surface finish (coating, plating) breaks away. Refer to Figure
Peened	-	A group of very small dents caused when the part is hit many times
Pick-up	-	The material from one surface becomes attached to a different surface. Usually caused when two surfaces are rubbed together without sufficient lubricant. Refer to Figure
Pierced	Hole in the part	The part has a hole made in it
Pitted	-	Small irregular shaped holes in the surface of a material. Usually caused because of corrosion or electrical discharge. Refer to Figure
Plugged	Clogged, obstructed, restricted passage	The flow is decreased or prevented because of blockage
Porous	Pock-marked, perforated weld	Small empty spaces in the material usually found in welds and materials that are cast. Refer to Figure
Rolled over	Lipped, turned metal	The edges of the part become rounded. Refer to Figure
Rough	-	When the operation (not the surface) is not smooth
Rubbed	Abraded	To move with pressure or friction against a different surface. Such as compressor rub
Ruptured	Blown, burst, split	The surface of the part is broken open because of an internal stress or force. Refer to Figure
Scored	-	A scratch or scratches of large depth (with some removal of the material) made with a sharp object during the operation of the part. Refer to Figure
Scratch	-	A small surface cut with not much depth made with a sharp object or particle. Material is not usually removed. Refer to Figure
Seized	Frozen, jammed, stuck	Movement between the parts is stopped because the clearance is not sufficient. Caused because of heat or unwanted particles
Shallow imperfection	An imperfection which appears to penetrate the surface finish texture, does not have a dark bottom and would not cause a stylus having a nose radius ranging in size from 0.030 in. - 0.0365 in. (0.762 mm - 0.927 mm) to hesitate (catch) when passed over it.
Sheared	Cut	Is when two surfaces move in relation to each other along the same axis in opposite directions. This will cause the details that hold the two surfaces together to break. Refer to Figure
Skidding	-	Is surface damage to balls, rollers and races of bearings. It is seen as an intermittant matt silver effect on the surface and occurs because of intermittant loads during use. Refer to Figure
Sludged	Gummed	Very small particles of unwanted material collected in one location
Softened	Perished	Below the specified elasticity
Spalled	Plucked	A rough broken area on the surface of a material. Usually caused because of surface cracks or inclusions when a load is put on the surface. Refer to Figure
Spinning		Damage caused when a bearing race is turned too much
Stretched	Growth	The part is made larger as a result of conditions of operation
Stripped	-	The removal of material by force. Usually related to threads and insulation
Superficial imperfection	An imperfection which disrupts the surface and appears smooth-edged but does not penetrate the surface roughness texture. This condition is so slight, considered less than a shallow imperfection, that a stylus need not be used to evaluate it.
Torn	-	The material is pulled apart. Refer to Figure
Untwisted	Unwound	An unsatisfactory decrease in the angular adjustment. The part tries to become straight
Worn	-	The material of the part is erroded away because of operation or use
Wrecked	-	The damage is too bad for continued use

SUBTASK 70-02-02-350-002 The Condition of Metal Parts

TYPE OF DAMAGE	RELATED DATA	RELATED CONDITION
Acceptable	OK	Satisfactory for continued use
Not inspected	-
Class of part	-	The nozzle guide vane class is the
too low		angular deviation between the airfoil
		chord and the buttresses
Class of part	-	The nozzle guide vane class is the
too high		angular deviation between the airfoil
		chord and the buttresses
Clearance above	-	Unsatisfactory tolerances have
maximum		collected. (Not because of wear)
Clearance above	-	Unsatisfactory tolerances have
minimum		collected. (Not because of wear)
Clearance end	-	-
too much
Compression or	-	Compression or tension load is lower
tension below		than specified
minimum
Compression or	-	Compression or tension load is higher
tension above		than specified
maximum
Damaged during	-	-
transit
Deterioration	-	-
in storage
Dimension below	-	Below the engineering drawing
minimum		dimension or other specified
		dimension
Dimension above	-	Above the engineering drawing
maximum		dimension or other specified
		dimension
Emission low	-	Is the low output of electrical tubes;
		it shows an unsatisfactory tube
Finish not to	-	Is the condition of the surface
specification		finish; not surface damage
Frequency out	-	The frequency of vibrations of a part
of limits		are above permitted limits
Hardness below	-	Found with Rockwell, Brinell or
limits		alternative hardnesss tests
Hardness above	-	Found with Rockwell, Brinell or
limits		alternative hardness tests
Magnetism low	-	Low or no magnetism of permanently
		magnetized parts
Mis-matched	-	A condition caused because of the
		incorrect relation of parts
Mis-positioned	Mis-aligned,	The incorrect installation of a part
	reversed, cocked	which results in damage to the part
		or related parts
Obsolete	Superseded	The part is not in use
Out of balance	-	The weight is not equally symmetrical
		around the axis. This condition is to
		be examined if there is no apparent
		damage
Out of round	Elongated	The diameters of the part are not
		constant
Out of square	-	The related surfaces are not at the
		specified right angle
Part removed	-	A part removed as a precaution until
pending		an investigation is done and a
investigation		technical decision is made on its
		condition
Received	-	-
disassembled
Resistance high	-	High electrical resistance in an
		electrical circuit that causes
		incorrect circuit operation
Resistance low	-	Low electrical resistance in an
		electrical circuit that causes
		incorrect circuit operation
Tension or	-	Tension or compression load is lower
compression		than is specified
below minimum
Tension or	-	Tension or compression load is higher
compression		than is specified
above maximum
Time expiration	Part retired	The part is not used because of a
		time limit
Voltage erratic	-	Caused because of the intermittant
		or irregular flow of current
Voltage - none	-	Caused because of an unwanted current
(circuit shorted		path to ground or between leads of
or grounded)		circuits that are usually at a
		different voltage
Voltage - none	-	Caused because an electrical circuit
(circuit open)		is not complete because of a break
		between electrical connections

1. 1. Adhesive failure.
    This is failure at the joint between the bonded surface and the adhesive. The adhesive stays on one of the surfaces.
    For honeycomb structures, adhesive failure can be divided in to two types.
    NOTE
    The adhesive will stay on the surface layer at the locations related to the honeycomb cells.
    Failure at the joint between the adhesive and the surface layer of the honeycomb. Adhesive stays on the honeycomb but not on the related position on the surface layer. Refer to Figure and Figure.
    Failure at the joint between the adhesive and the honeycomb. The adhesive stays on the surface layer but not on the honeycomb. This is usually known as pull out. Refer to Figure.
    NOTE
    Unbond which occurs in composites can also occur in honeycomb structures with metal perforate and non-perforate surface layers.
  2. Cohesive failure.
    This is failure in the adhesive material. The adhesive stays on each surface. Refer to Figure.
2. Delaminated.
  This is the separation of layers in a composite laminate. Refer to Figure.
  NOTE
  Cracks can occur in locations that are filled or have large quantities of resin. These are only surface defects and must be correctly identified from cracks in the composite laminate. Refer to Figure.
3. Cracked or split.
  A crack or split through a composite laminate; is seen as a small opening in the composite surface layer or the complete composite thickness. It is usually caused when the material is hit or because of distortion. Refer to Figure.
4. Fretted.
  This is seen as a rubbed surface with the protection removed from the fibers, this can result in broken fibers. Refer to Figure.
5. Eroded.
  This is seen as the removal of the surface resin layer caused because of the effects of weather. When the protection is removed from the fibers it can make the surface rough. It is possible for the fibers to become eroded. Refer to Figure.
6. Cavity.
  This is an empty space that occurs usually in the surface layers with a large quantity of resin or infilled locations. Refer to Figure.
7. 1. Sharp object.
    Usually a split or a crack, possibly with related delamination near the damage. Refer to Figure.
    NOTE
    In honeycomb sandwich structures, impact damage could include other types of damage to the honeycomb.
  2. Blunt object.
    Usually delamination of the layers with a possible related split, crack or unbond. Damage usually extends out of the immediate location of the damage. Refer to Figure.
8. Torn fibers.
  Strips of lifted surface fibers, pulled and peeled along the fiber length. Damage is frequently made larger because of the air flow until the fiber breaks. Refer to Figure.
9. 1. Blistered.
    This is bubbles on the surface caused because of local delamination below the surface layer. Refer to Figure.
  2. Scorched.
    This is seen as a change in color of the surface layer.
  3. Resin degradation.
    This is deterioration of the resin of a composite laminate, at the surface and also internally, which results in delamination and loose fibers. Refer to Figure.
10. Fluid diffusion.
  This is fluid leakage through a composite material that has high porosity. This is usually related to wet lay up assemblies.