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Basic Principles of surgery.ppt scientific research
Basic Principles Principles of Ultrasonic Ultrasonic Testing Testing
Krautkramer NDT Ultrasonic Systems
Basic Principles Principles of Ultrasonic Ultrasonic Testing Testing xamp es o osc a on a spring
earth
Krautkramer NDT Ultrasonic Systems
Basic Principles Principles of Ultrasonic Ultrasonic Testing Testing xamp es o osc a on a spring
earth
Krautkramer NDT Ultrasonic Systems
Basic Principles Principles of Ultrasonic Ultrasonic Testing Testing
The ball starts to oscillate as soon as it is ushed Krautkramer NDT Ultrasonic Systems
Basic Principles Principles of Ultrasonic Ultrasonic Testing Testing
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Movement of the ball over time
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Fre uenc
Time
From the duration of one oscillation e requency num er o oscillations per second) is calculated:
One full osc a on
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing The actual displacement a is termed as:
a Time
0
90
180
270
360 Phase
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Spectrum of sound Fre uenc ran e Hz
Exam le
Descri tion
-
20 - 20.000 >
.
Audible sound trasoun
Krautkramer NDT Ultrasonic Systems
Speech, music at,
uartz crysta
Basic Principles of Ultrasonic Testing om c s ruc ures
• low density •
• medium density • forces
Krautkramer NDT Ultrasonic Systems
• high density • • crystallographic structure
Basic Principles of Ultrasonic Testing n ers an ng wave propaga on:
Ball = atom
Spring = elastic bonding force
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing
T
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing
During one oscillation T the wave ron propaga es y e s ance :
Distance travelled
From this we derive: or
Wave equation Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Sound propagation
Longitudinal wave
Direction of propagation
Direction of oscillation
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Sound propagation Transverse wave Direction of oscillation
Direction of propagation
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Wave propagation Transverse waves only propagate in solid bodies. Due to the different t e of oscillation transverse waves travel at lower speeds. Sound velocity mainly depends on the density and Emo u us o e ma er a . Air Water Steel, long Steel, trans
330 m/s 1480 m/s 5920 m/s 3250 m/s
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Reflection and Transmission s soon as a soun wave comes o a c ange n ma er a characteristics ,e.g. the surface of a workpiece, or an internal inclusion, wave propagation will change too:
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing e av our a an n er ace Medium 1
Basic Principles of Ultrasonic Testing mp u e o soun
Water - Steel
ransm ss ons:
Co
er - Steel
• Strong reflection • No reflection • Double transmission • Single transmission
Krautkramer NDT Ultrasonic Systems
Steel - Air • Strong reflection w nver e p ase • No transmission
Basic Principles of Ultrasonic Testing ezoe ec r c
ec
Batter
Piezoelectrical Crystal (Quartz) Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing ezoe ec r c
ec
The crystal gets thicker, due to a distortion of the crystal lattice Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing ezoe ec r c
ec
The effect inverses with polarity change Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing ezoe ec r c
ec
oun wave with frequency f
U(f)
An alternating voltage generates crystal oscillations at the frequency f Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing ezoe ec r c
ec
Short pulse ( < 1 µs )
A short voltage pulse generates an oscillation at the crystal‘s resonant fre uenc f Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing ecep on o u rason c waves , vibration which then causes electrical voltages at the crystal surfaces. Electrical energy
crystal
Krautkramer NDT Ultrasonic Systems
rason c wave
Basic Principles of Ultrasonic Testing Ultrasonic Probes Electrical matching Cable
crystal Dam in
Strai ht beam robe
TR- robe
Krautkramer NDT Ultrasonic Systems
An le beam robe
Basic Principles of Ultrasonic Testing RF signal (short)
ns
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing RF signal (medium)
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Sound field
Focus
Crystal
Angle of divergence 6
N
Near field
Far field
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Ultrasonic Instrument
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Ultrasonic Instrument
Uh
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Ultrasonic Instrument
Uh
0
2
4
6
8
10
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Ultrasonic Instrument + Uv
-
+ Uh
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Block diagram: Ultrasonic Instrument amplifier
IP
screen BE
probe work iece Krautkramer NDT Ultrasonic Systems
horizontal sweep
Basic Principles of Ultrasonic Testing Sound reflection at a flaw s
Sound travel path
Work piece
Krautkramer NDT Ultrasonic Systems
Flaw
Basic Principles of Ultrasonic Testing Plate testing IP BE
F
late
delamination
0
2
4
6
8
IP = Initial pulse F = Flaw =
Krautkramer NDT Ultrasonic Systems
ac wa ec o
10
Basic Principles of Ultrasonic Testing Wall thickness measurement
s s
Krautkramer NDT Ultrasonic Systems
Basic Principles of Ultrasonic Testing Through transmission testing Through transmission signal
1
T
R
1
2
0
Flaw
Krautkramer NDT Ultrasonic Systems
2
4
6
8
10
Basic Principles of Ultrasonic Testing Weld inspection a = s sinß
F
'
s
-
d' = s cosß 0
20
40
60
80
100
d = 2T - t'
a a'
x
Work piece with welding
s
Lack of fusion
Krautkramer NDT Ultrasonic Systems
= s = sound path a = surface distance a‘ = reduced surface distance ‘= d = actual depth T = material thickness
Basic Principles of Ultrasonic Testing Straight beam inspection techniques: Direct contact,