BS EN 16018:2011 pdf download – Non-destructive testing — Terminology — Terms used in ultrasonic testing with phased arrays
1 Scope
This European Standard defines terms used inultrasonic testing with phased arrays.
Terms relating to sound
2.1
side lobes
beams,generated by a transducer，that deviatefrom the direction of the main beam
2.2
grating lobes
parasitic replications of the main beam caused byspatial undersampling (pitch between elementscompared to wavelength)
3Terms relating to test equipment
3.1 Arrays
3.1.1
array
piezo-electric plate divided into several elements
3.1.2
array elementelement
smallest part of the array acting as a transducerNOTESee Figure 11.
3.1.3
arrangement of the array
distribution of all the elements in an array
3.1.4
linear array1D linear array
array of elements arranged in a single straight lineNOTESee Figure 1.
3.1.5
annular array
arrayofring-shapedelementsarrangedconcentrically where the major transmitting axis isaxial
NOTESee Figure 2.
3.1.6
annular sectorial array
annular array with the rings divided into sectorsNOTESee Figure 3 and Figure 9.
3.1.7
encircling array
array arranged on a complete or partial circle,where the major transmitting axis is radial
NOTESee Figure 4 and Figure 7.
3.1.8
convex array
encircling array typically used for the inspection oftubes from the inside
3.1.9
concave array
encircling array typically used for the inspection oftubes from the outside
3.1.10
dual array probe
probe with separate arrays for transmitting andreceiving
NOTESee Figure 5.
3.1.11
virtual probe
group ofindividualarray elementsoperatedsimultaneously with adapted delay laws
3.1.12
matrix array
two-dimensional array of equal or non-equal sizedelements
EXAMPLE
See Figure 3.
3.1.13
2D matrix array
rectangular matrix array
NOTESee Figure 6 and Figure 8.
3.1.14
pitch
distance between the same edges or centres of twoadjacent elements
NOTE For linear arrays see Figure 10.
3.1.15
space between elementsgap between elements
distance between two adjacent elementsNOTEFor linear arrays see Figure 10.
3.1.16
active aperture
group of active elements when transmitting and/orreceiving
3.1.17
elementary aperture
active aperture made of only one element
3.1.18
primary axis of an array
main axis for beam-steering parallel to the width ofthe elements
NOTESee Figure 8.
3.1.19
secondary axis of an array
axis perpendicular to the primary axisNOTESee Figure 8.
3.1.20
reference point on the wedge
coordinates of the point on the wedge which isused to position a defined point of the array
3.1.21
sensitivity curve of an array
representation of the sensitivity of each elementsuccessively connected to the same channel, whenusing a flat reflector much larger than the apertureof the array
3.1.22
natural refracted beam angle
angle between the refracted beam axis and the
normal to the interface without electronic beam-steering
NOTESee Figure 11.
3.1.23
deflection plane
3.1.24
steering angle
angle between the beam axis and the projection ofthe normal to the test object surface on thedeflection plane
NOTESee Figure 12 a).
3.1.25
steering range
range of steering anglesNOTESee Figure 12 a).
3.1.26
skewing
3.1.27
skew angle
angle between the traces of the deflection planeand the plane of natural refraction on the surface ofthe test object
NOTESee Figure 12 b).