teori dasar ultrasonik
TRANSCRIPT
Krautkramer NDT Ultrasonic Systems
Introduction toUltrasonic Testing
SD 218
Introduction toUltrasonic Testing
SD 218© SLAMET WALUYO
PT. MULTI KHARISMA PERKASA2007
Krautkramer NDT Ultrasonic Systems
socket
matching-element
damping-block
crystalprotecting face(probe delay)
housing
workpiece Sound pulse
Straight beam probe
Krautkramer NDT Ultrasonic Systems
crystal
perspex wedge(probe delay)
damping blocks
socket
housing
workpiece Sound pulse
Angle beam probe
Krautkramer NDT Ultrasonic Systems
near field
far field
acoustical axis (central beam)
N = near field length
= angle of divergence
3
Sound field
Krautkramer NDT Ultrasonic Systems
Flaw detection
Krautkramer NDT Ultrasonic Systems
10 20 30 40
Flaw detection
Krautkramer NDT Ultrasonic Systems
10 20 30 40
Flaw detection
Krautkramer NDT Ultrasonic Systems
Bad flaw orientation
Krautkramer NDT Ultrasonic Systems
crack
Improper flaw location
Krautkramer NDT Ultrasonic Systems
10 20 30 40
crack
Angle reflection
Krautkramer NDT Ultrasonic Systems
Angle reflection
Krautkramer NDT Ultrasonic Systems
10 20 30 40
Vertical, near surface flaw
Krautkramer NDT Ultrasonic Systems
10 155 10 155T R
a1
Tandem technique (top)
Krautkramer NDT Ultrasonic Systems
10 155 10 155T R
a 2
Tandem technique (middle)
Krautkramer NDT Ultrasonic Systems
10 155 10 155T R
a 3
Tandem technique (bottom)
Krautkramer NDT Ultrasonic Systems
10 20 30 40
Improper flaw orientation
Krautkramer NDT Ultrasonic Systems
10 20 30 40
Perfect flaw orientation
Krautkramer NDT Ultrasonic Systems
sound beam
flat defect
15105
reflected sound waves
Flaw detectability with improper flaw orientation
Krautkramer NDT Ultrasonic Systems
s
Flaw distance
Krautkramer NDT Ultrasonic Systems
start signal(pulse)
finish signal(echo)
transmitter
transit timemeasurement
probe
work piece
sound transitpath
Stop-watch
Principle of transit time measurement
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
CRT / A-scan display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
sound wave starts at crystal
light point
transmittertransmittertransmission
pulse
Priciple, transmission pulse
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
sound wave
transmittertransmitter
Priciple, sound wave in the workpiece
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
transmittertransmitter
Priciple, sound pulse at the back wall
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
transmittertransmitter
Priciple, sound pulse at the coupling surface
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
back wallecho
transmittertransmitter
Priciple, echo display and 2nd run
Krautkramer NDT Ultrasonic Systems
2 4 6 8 10
protecting face
crystal
probe
electricalzero
(initial pulse)
mechanicalzero
(surface)
Probe delay
Krautkramer NDT Ultrasonic Systems
electicalzero
(initial pulse)
mechanicalzero
(surface)sound wave
work piece
delay(wedge)
probe 0 2 4 6 8 10
Probe delay
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probeback wall
echo
flaw
flawecho
Flaw location and echo display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
back wallecho
flaw
flawecho
Flaw location and echo display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
work piece
probe
back wallecho
flaw
flawecho
Flaw location and echo display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
flaw echocoveredby initialpulse
work piece
probe
back wallecho
flaw
Flaw location and echo display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
back wallecho:
without
with flaw
work piece
probe
flaw
Flaw location and echo display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
flaw echosequence
work piece
probe
flaw
Flaw location and echo display
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
dead zone
Dead zone
Krautkramer NDT Ultrasonic Systems
10 20
Near surface detectability with angle beam pobes
Krautkramer NDT Ultrasonic Systems
receiversocket
transmittersocket
damping blocks
crystal
delay
acousticalbarrier
TR-probe / dual crystal probe
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
IP
BE
work piece
TR-probe
Probe delay with TR-probes
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
IP
BE
flaw
cross talkecho
flawecho
TR-probe
Cross talk at high gain
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
0 100 mm50
steel, L
div.
Range calibration
Krautkramer NDT Ultrasonic Systems
5 10 15
70°
45°
100
mm
60°
Calibration block 1 with angle beam probes
Krautkramer NDT Ultrasonic Systems
5 10 15
0 2 4 6 8 10
100 mm
1st echo from circular section
Krautkramer NDT Ultrasonic Systems
5 10 15
0 2 4 6 8 10
100 mm 200 mm 300 mm
Echo sequence from 100 mm radius
Krautkramer NDT Ultrasonic Systems
s = 25 mms = 100 mms = 175 mmetc.
1
2
3
this wave will be absorbed !
25 mm radius of calibration block 2
Krautkramer NDT Ultrasonic Systems
s = 50 mms = 125 mms = 200 mmetc.
1
2
3
50 mm radius of calibration block 2
Krautkramer NDT Ultrasonic Systems
5 10 15
0 2 4 6 8 10
0 100 mmsteel
100 mm range calibration on K2
Krautkramer NDT Ultrasonic Systems
51015
work piece reflector
s
0 2 4 6 8 10
s = k•R
s = sound pathk = scale factorR = screen reading
Flaw location
Krautkramer NDT Ultrasonic Systems
flaw location
a
s d
Sound entry point projectionpoint
a = s•sin ßd = s•cos ß
ß
ßß = probe angles = sound patha = surface distanced = depth
"flaw triangle"
Flaw location with angle beam probes
Krautkramer NDT Ultrasonic Systems
51015
work piece reflector
aa'
s d
x
index point -front edge of probe
a = surface distancea' = reduced surface distancex = x-value = distance:
Flaw location with angle beam probes
Krautkramer NDT Ultrasonic Systems
51015
apparent flaw location
a
sd = apparent depth
T
Flaw location with an angle beam probe on a plate
Krautkramer NDT Ultrasonic Systems
51015
apparent flaw location
real flaw location
a
s d
d'
d' = apparent depthd = real depthT = work piece thickness
T
a = s • sind‘ = s • cosd = 2T - d
a = s • sind‘ = s • cosd = 2T - d
Flaw location with an angle beam probe on a plate
Krautkramer NDT Ultrasonic Systems
Large defects parallel to the scanning surface
Krautkramer NDT Ultrasonic Systems
Scanning the edge of the defect
Flaw echo drops to 50% of its maximum value
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 100 2 4 6 8 10 0 2 4 6 8 10
IP BER IP BER IP BER
Flaw sizes and echo amplitudes
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
0 2 4 6 8 10
0 2 4 6 8 10
IP BER
IP BER
IP BER
Flaw distances and echo amplitudes
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
IP BEF
F
instrument gain: G = 34 dB
80 %
Defect evaluation by comparison - 1
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
IP BER
instrument gain: 34 dB
Defect evaluation by comparison - 2
Krautkramer NDT Ultrasonic Systems
0 2 4 6 8 10
IP BERE
+ 8 dB
instrument gain: 42 dB
Defect evaluation by comparison - 3
Krautkramer NDT Ultrasonic Systems