DEFECTS ATLAS FOR SURFACE DEFECTS ON COLD ROLLED STEEL http://www.iitk.ac.in/robotics http://www.iitk.ac.in/robotics/project!ists/sai /project!ists/sai!/at!as.ht"!#RUST !/at!as.ht"!#RUST
This page is primarily meant to introduce non-experts to some of the types of defects that arise in Cold Rolling. The images used in these atlas were taken under varying lighting conditions at the very initial phases of the Surface Defect Inspection ro!ect. List o$ De$ects •
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•
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•
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R&%% *"R(
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R&%%$D I# SC"%$
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R+T+R$
•
R+ST
•
SC"'
•
SCR"TC)
•
S%I,$R
•
S*II
•
+#D$R IC(%I#
•
/",I#$SS
ANNEAL COLOR De$ect Description:
Coloured Coloured markings usually found along the coil edges in hood annealed material. The colour can vary from light 0rown to deep 0lue. %ossib!e Ca&ses: •
)igh oxygen content in the protective gas for annealing.
•
%eakage in sand sealing 0ase.
•
Sudden drop of protective gas pressure causing sucking in of air.
Re"e'ia! (eas&res: •
revent %eakage during hood annealing.
•
$nsure protective gas has low &1 content.
%ossibi!ities o$ con$&sion with other 'e$ects: They could 0e mistaken for prominent oil marks or light grease marks.
Attribute
Value
Shop name
Shearing Line
Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Left/Do!n
Flash "sed
#es
$ic Type
Color
Coloured Coloured markings usually found along the coil edges in hood annealed material. The colour can vary from light 0rown to deep 0lue. %ossib!e Ca&ses: •
)igh oxygen content in the protective gas for annealing.
•
%eakage in sand sealing 0ase.
•
Sudden drop of protective gas pressure causing sucking in of air.
Re"e'ia! (eas&res: •
revent %eakage during hood annealing.
•
$nsure protective gas has low &1 content.
%ossibi!ities o$ con$&sion with other 'e$ects: They could 0e mistaken for prominent oil marks or light grease marks.
Attribute
Value
Shop name
Shearing Line
Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Left/Do!n
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Shearing Line
Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
%
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
&'(
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
$orta)le Flourescent
Light Distance
%
Light Angle
*ight/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
+o
$ic Type
Color
Attribute
Value
Shop name
Steel Cutter
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient Lighting
Camera Distance
5
Camera Angle
Left/Do!n
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Steel Cutter
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient Lighting
Camera Distance
5
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
Color
)LAC* %ATC+ De$ect Description: Dark 0lack stains on the surface distri0uted either as 0ands2clusters. They are generally of irregular shape and can vary from small to reasona0ly 0ig si3es4 can appear on 0oth sides. %ossib!e Ca&ses: &il2emulsion residues on the strip surface which get transformed to car0on residue durind hood annealing Re"e'ia! (eas&res: •
$mulsion wiping after Tandem *ill air-!ets.
•
Degreasing of coil surface 0y $lectrolytic cleaning line after Tandem *ill.
%ossibi!ities o$ con$&sion with other 'e$ects: Dark and prominent 0lack patches mistaken for grease marks.
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
-
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
&(
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
.
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Slitting Line
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
Color
CO,L )REA* De$ect Description: Creases2Ridges4 transverse to the rolling direction. enerally covers total width of the strip. It may also 0e found near the edges with regular or irregular spacing. 5ormed during uncoiling of the strip after annealing. %ossib!e Ca&ses: •
•
)igh yield point elongation particularly with low yield strength values. )igher 0ending stresses induced in strip due to smaller diameter of guide rolls 6S-rolls7 and greater strip thickness.
Re"e'ia! (eas&res: Increase speed of uncoiling at S*4 particularly for thicker guages.
Attribute
Value
Shop name
Shearing Line
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
&'(
Attribute
Value
Shop name
Shearing Line
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
&'(
+OLE De$ect Description: )oles are discontinuities of the material extending from the top to the 0ottom. enerally4 they have locali3ed presence on the strip surface and can 0e present randomly. Si3e8 +sually varies from 9 to :; mm4 sometimes even 0igger. Shape8 Irregular. %ossib!e Ca&ses: •
•
•
Seperation of Rolled in Sca02$xternal *atter. *echanical Damage prior to Colled Rolling leading to locali3ed thinning and su0se
Re"e'ia! (eas&res: •
roper scarfing of Sla0s.
•
Careful )andling of Coils 'etween hot and cold rolling.
•
Improve steel cleanliness.
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Am)ient
Camera Distance
.
Camera Angle
*ight/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
,NDENT De$ect Description: Indentation 6depressions7 can 0e distri0uted at definite distances apart or irregularly throughout the length and width of the stock. %ossib!e Ca&ses: These are mainly caused 0y damaged rolls4 0y protur0ences on the rools ar rollers. The distance 0etween the periodically appearing defects often provides indications of origin and source. Re"e'ia! (eas&res •
The work rolls should 0e safeguarded againt foreign matter which may roll in.
•
Regular cleaning and inspection of the the work rolls and pinch rolls is re
%ossibi!ities o$ con$&sion: Indentation can 0e mistaken for minute 0listering and spilliness.
Attribute
Value
Shop name
Slitting Line
Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
.
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Am)ient
Camera Distance
.
Camera Angle
Do!n/Mid
Flash "sed
#es
$ic Type
&'(
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Do!n/Mid
Flash "sed
+o
$ic Type
&'(
,RON %ART,CLES Defect Description8 They are patches on the rolled surface4 appearing as large num0er of minute iron particles spread over that area. They largely occur in 0ands. the particles are strongly adhered to the surface4 and amount to a highly rough surface. ossi0le Causes8 The mechanical wear of the sheet material due to friction results in minute iron particles4 which are transferred from the work rolls to the rolled surface. Remedial *easures Regular cleaning of the work rolls4 transfer rolls and stretcher rolls. ossi0ilities of confusion8 rominent iron-particles could 0e mistaken for fine dents.
Attribute
Value
Shop name
Slitting Line
Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
*ight/Mid
Flash "sed
+o
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
*ight/Mid
Flash "sed
#es
$ic Type
&'(
LA(,NAT,ON
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, FLAT
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
%ARALLEL )AND ,(%RESS,ON De$ect Description
Two pairs of continuous parallel lines o0served on the strip surface along the rolling direction. ap 0etween the lines8=;mm ap 0etween the 0ands8=>;mm6Centre to Centre7. %ossib!e Ca&ses: Due to the prolonged usage4 the 0ack up rolls Tensioning Device which su0se
%ift up the work rolls of the tensioning device in slitting lines.
•
Change all the work rolls of the tensioning device.
Attribute
Value
Shop name Movement and Shape
Stationary, FLAT
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Left/Do!n
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Center/Mid
Camera Distance
5
Camera Angle
Left/Do!n
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
infinity
Light Angle
Center/Mid
Camera Distance
5
Camera Angle
Left/Do!n
Flash "sed
#es
$ic Type
Color
%,NC+ (AR* De$ect Description %inear markings of single or periodic occurence diagonal to rolling direction %ossib!e Ca&ses: •
Single results from lack of flatness causing pinch folding in the roll gap of S*.
•
eriodic roll marks results from transfer of pinch marks from work rolls of S*
Re"e'ia! (eas&res: Improve strip flatness at CR* Change S* work rolls. %ossibi!ities o$ con$&sion with other 'e$ects "lthough they are of characteristic identification4 0ut they could 0e mistaken for pitting defects and those due to rolled in matter.
Attribute
Value
Shop name Movement and Shape
Stationary, Coil
Type of Lighting
Sodium
Light Distance
5
Light Angle
Left/Do!n
Camera Distance
.
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name Movement and Shape
Stationary, coil
Type of Lighting
Sodium
Light Distance
5
Light Angle
Left/Do!n
Camera Distance
.
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name Movement and Shape
Stationary, Coil
Type of Lighting
Sodium
Light Distance
5
Light Angle
Left/Do!n
Camera Distance
.
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
&'(
ROLL (AR*
De$ect Description: Surface markings4 generally depressions of various shapes attri0uta0le to defective work cell2pinch roll surface. "ppearance8Smooth shinning patches. Shape8Irregular &ccurance8eriodic on strip surface.enerally found on one side of the strip. %ossib!e Ca&ses: /elding of metallic pieces like detached slivers4 sca0s etc. on work roll2pinch roll surface. Re"e'ia! (eas&res: •
Identify the rolls causing the defect 0y measuring the gap 0etween the marks.
•
Clear roll surface.
•
Change rolls
%ossibi!ities o$ con$&sion with other 'e$ects: They could 0e mistaken for minute 0listering and spilliness
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
infinity
Light Angle
Am)ient
Camera Distance
-
Camera Angle
Left/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
porta)le Flourescent
Light Distance
5
Light Angle
Center/Mid
Camera Distance
Camera Angle
Camera/Mid
Flash "sed
#es
$ic Type
Color
ROLLED ,N SCALE Defect Description8 &ther types of rolled in defects are marks in the surface caused 0y rolled in metallic or non-metallic foreign 0odies of varying shape and si3e. %argely4 they could 0e identified as scales on the sheet surface &ccurence8 Rolled in defects are caused 0y foreign 0odies imprinted in the stock during rolling. ossi0ilities of Confusion8 Rolled in types of defects can 0e mistaken for identations when the rolled foreign 0ody has 0een removed from the defect area. Similar defects can also 0e caused in the su0se
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
porta)le Flourescent
Light Distance
5
Light Angle
Centre/Mid
Camera Distance
-
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
porta)le Flourescent
Light Distance
5
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
*ight/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
porta)le Flourescent
Light Distance
-
Light Angle
Centre/up
Camera Distance
5
Camera Angle
*ight/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
porta)le Flourescent
Light Distance
-
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
*DCS La)
Movement and Shape
Stationary, Flat
Type of Lighting
porta)le Flourescent
Light Distance
01
Light Angle
Diffused Lighting
Camera Distance
5
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
+one
RU%TURE
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
-
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
-
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
RUST De$ect Description: atches of rust or randomly distur0ed4 normally of irregular shapes o0served on 0oth surfaces. Colour8 Reddish 0rown to 0lack. %ossib!e ca&ses: •
resence of a
•
rolonged storage of coils 0etween processing stages at CR*.
•
)igh atmospheric humidity
Re"e'ia! (eas&res: •
$mulsion wiping after Tandem Rolling.
•
Reduce coil storage time 0etween processes.
•
"rrest acid carry over from picking line 0y proper s
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
Am)ient
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
SCA)
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
21
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
21
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Flourescent
Light Distance
01
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
SCRATC+ De$ect Description: Scratches are mechanical damages in width4 depth and length at the surface. They are mostly parallel or at right angles to the rolling direction. They may 0e slightly rolled over and seldom contain scale. %ossib!e Ca&ses: rimarily caused 0y friction 0etween the stock and parts of the e
Attribute
Value
Shop name
Tandem mill
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Ambient
Camera Distance
5
Camera Angle
Centre/Left
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Left/Mid
Camera Distance
5
Camera Angle
Left/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Flourescent
Light Distance
01
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
&'(
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Left/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
*DCS La)
Movement and Shape
Stationary, Flat
Type of Lighting
Flourescent
Light Distance
5
Light Angle
Left/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
&'(
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
Am)ient
Light Angle
Left/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
*DCS La)
Movement and Shape
Stationary, Flat
Type of Lighting
$orta)le Flourescent
Light Distance
-
Light Angle
Centre/Up
Camera Distance
2
Camera Angle
Left/Mid
Flash "sed
#es
$ic Type
Color
SL,-ER De$ect Description: Irregular flaky overlapping material with non-metallic inclusions or scale under it. It is found along the rolling direction and can appear on 0oth surfaces.Sometimes referred as Shell. %ossib!e Ca&ses: Slag or non metallic inclusion entrapment. Re"e'ia! (eas&re"ents:
•
•
revent slag carry over during tapping
•
+se clean ingot moulds roper scarfing of sla0s
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Flourescent
Light Distance
01
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
La)
Movement and Shape
Stationary, Flat
Type of Lighting
Flourescent
Light Distance
01
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Centre/Mid
Flash "sed
#es
$ic Type
Color
S%(,,
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
Am)ient
Light Angle
Ambient
Camera Distance
01
Camera Angle
Centre/Do!n
Flash "sed
+o
$ic Type
Color
Attribute
Value
Shop name
Steel Cutters
Movement and Shape
Stationary, Flat
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Ambient
Camera Distance
01
Camera Angle
Left/Do!n
Flash "sed
+o
$ic Type
Color
UNDER %,C*L,N De$ect Description: This defect is characteri3ed irregular dark patches spread irregularly over the whole surface of the steel sheet. The patches are finger like and angular in the form. %ossib!e Ca&ses: This defect is caused due to the im0alance 0etween the composition of the acid and the time of reaction in the ickling *ill. Re"e'ia! (eas&res: This defect originates prior to the cold rolling mill4 hence it could spoil the final rolled surface4 it is important to inspect the reaction time and the composition of the acidic vehicle in the rickling *ill.
Attribute
Value
Shop name
Dispatch
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Ambient
Camera Distance
-
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
Color
Attribute
Value
Shop name
Dispatch
Movement and Shape
Stationary, Coil
Type of Lighting
Am)ient
Light Distance
nfinity
Light Angle
Am)ient
Camera Distance
5
Camera Angle
Centre/Do!n
Flash "sed
#es
$ic Type
Color
A-,NESS De$ect Description: Cross ripples2undulations of varying magnitude appear along the long direction either at the edge or middle of the strip2sheet. Centre 0uckles are located at the middle of strip4 while edge waves appear at the edges. 'uckle )eight8 *ostly upto ?mm for precision levelled material. %ossib!e Ca&ses: •
*ismatch of roll gap with in-comming strip crown leads to differencial elongation along the rolling direction 0oth at )ot @ Cold rolling stage.
•
Incorrect profile or positioning of support rollers.
•
Contact with edge guides.
Re"e'ia! (eas&res: •
Reduction of waviness through precision leveller2stretch leveller.
•
Control of waviness at 0oth )S* and CR* 0y work roll 0ending and selective cooling.
Attribute
Value
Shop name
Slitting Line
Movement and Shape
Stationary, Flat
Type of Lighting
Sodium
Light Distance
nfinity
Light Angle
Centre/Mid
Camera Distance
5
Camera Angle
Left/Mid
Flash "sed
#es
$ic Type
Color
