2010 SECTION V ARTICLE 5

ARTICLE 5
ULTRASONIC EXAMINATION METHODS FOR
MATERIALS

T-510 SCOPE not require requalification of the written procedure. All

changes of essential or nonessential variables from the
This Article provides or references requirements, which
value, or range of values, specified by the written procedure
are to be used in selecting and developing ultrasonic exami-
shall require revision of, or an addendum to, the written
nation procedures for parts, components, materials, and all
procedure.
thickness determinations. When SA, SB, and SE docu-
ments are referenced, they are located in Article 23. The
referencing Code Section shall be consulted for specific T-530 EQUIPMENT
requirements for the following: T-531 Instrument
(a) personnel qualification/certification requirements;
A pulse-echo type of ultrasonic instrument shall be used.
(b) procedure requirements/demonstration, qualifica-
The instrument shall be capable of operation at frequencies
tion, acceptance;
over the range of at least 1 MHz to 5 MHz, and shall be
(c) examination system characteristics;
equipped with a stepped gain control in units of 2.0 dB or
(d) retention and control of calibration blocks;
less. If the instrument has a damping control, it may be
(e) extent of examination and/or volume to be scanned; used if it does not reduce the sensitivity of the examination.
(f) acceptance standards; The reject control shall be in the “off” position for all
(g) retention of records, and examinations unless it can be demonstrated that it does
(h) report requirements. not affect the linearity of the examination.
Definitions of terms used in this Article are contained
in Mandatory Appendix III of this Article.
T-532 Search Units
The nominal frequency shall be from 1 MHz to 5 MHz
T-520 GENERAL unless variables such as production material grain structure
require the use of other frequencies to assure adequate
T-521 Basic Requirements
penetration or better resolution. Search units with con-
The requirements of this article shall be used together toured contact wedges may be used to aid ultrasonic cou-
with Article 1, General Requirements. pling.

T-522 Written Procedure Requirements T-533 Couplant

T-533.1 General. The couplant, including additives,
T-522.1 Requirements. Ultrasonic examination shall
shall not be detrimental to the material being examined.
be performed in accordance with a written procedure,
which shall, as a minimum, contain the requirements listed T-533.2 Control of Contaminants
in Table T-522. The written procedure shall establish a (a) Couplants used on nickel base alloys shall not con-
single value, or range of values, for each requirement. tain more than 250 ppm of sulfur.
(b) Couplants used on austenitic stainless steel or tita-
T-522.2 Procedure Qualification. When procedure
nium shall not contain more than 250 ppm of halides (chlo-
qualification is specified by the referencing Code Section,
rides plus fluorides).
a change of a requirement in Table T-522 identified as an
essential variable from the specified value, or range of
values, shall require requalification of the written proce- T-534 Calibration Block Requirements
dure. A change of a requirement identified as a nonessential The material from which the block is fabricated shall
variable from the specified value, or range of values, does be of the same product form, material specification or

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ARTICLE 5 2010 SECTION V

TABLE T-522
VARIABLES OF AN ULTRASONIC EXAMINATION PROCEDURE
Essential Nonessential
Requirement Variable Variable

Material types and configurations to be examined, including thickness

dimensions and product form (castings, forgings, plate, etc.) X ...
Personnel qualification requirements ... X
Personnel performance requirements, when required X ...
The surfaces from which the examination shall be performed X ...
Surface condition (examination surface, calibration block) ... X
Couplant: brand name or type ... X
Technique(s) (straight beam, angle beam, contact, and/or immersion) X ...
Angle(s) and mode(s) of wave propagation in the material X ...
Search unit type(s), frequency(ies), and element size(s)/shape(s) X ...
Special search units, wedges, shoes, or saddles, when used X ...
Ultrasonic instrument(s) X ...
Calibration [calibration block(s) and technique(s)] X ...
Directions and extent of scanning X ...
Automatic alarm and/or recording equipment, when applicable ... X
Scanning (manual vs. automatic) X ...
Method for sizing indications X ...
Computer enhanced data acquisition, when used X ...
Records, including minimum calibration data to be recorded (e.g., instrument
settings) ... X
Scan overlap (decrease only) X ...

equivalent P-Number grouping, and heat treatment as the T-560 CALIBRATION

material being examined. For the purposes of this para- T-561 Instrument Linearity Checks
graph, P-Nos. 1, 3, 4, 5A through 5C, and 15A through
The requirements of T-561.1 and T-561.2 shall be met
15F materials are considered equivalent. The finish on the
at intervals not to exceed three months for analog type
scanning surface of the block shall be representative of the
instruments and one year for digital type instruments, or
scanning surface finish on the material to be examined.
prior to first use thereafter.
T-534.1 Tubular Product Calibration Blocks T-561.1 Screen Height Linearity. The ultrasonic
(a) The calibration reflectors shall be longitudinal instrument’s (excludes instruments used for thickness mea-
(axial) notches and shall have a length not to exceed 1 in. surement) screen height linearity shall be evaluated in
(25 mm), a width not to exceed 1⁄16 in. (1.5 mm), and depth accordance with Mandatory Appendix I of Article 4.
not to exceed 0.004 in. (0.10 mm) or 5% of the nominal
wall thickness, whichever is larger. T-561.2 Amplitude Control Linearity. The ultrasonic
(b) The calibration block shall be long enough to simu- instrument’s (excludes instruments used for thickness mea-
late the handling of the product being examined through surement) amplitude control linearity shall be evaluated in
the examination equipment. accordance with Mandatory Appendix II of Article 4.

T-534.2 Casting Calibration Blocks. Calibration T-562 General Calibration Requirements

blocks shall be the same thickness ±25% as the casting to T-562.1 Ultrasonic System. Calibrations shall include
be examined. the complete ultrasonic system and shall be performed
T-534.3 Bolting1 Material Calibration Blocks and prior to use of the system in the thickness range under
Examination Techniques. Calibration blocks in accor- examination.
dance with Fig. T-534.3 shall be used for straight beam T-562.2 Calibration Surface. Calibrations shall be per-
examination. formed from the surface (clad or unclad; convex or con-
cave) corresponding to the surface of the material from
which the examination will be performed.
1
“Bolting” as used in this Article is an all-inclusive term for any type
of threaded fastener that may be used in a pressure boundary bolted T-562.3 Couplant. The same couplant to be used dur-
flange joint assembly such as a bolt, stud, studbolt, cap screw, etc. ing the examination shall be used for calibration.

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FIG. T-534.3 STRAIGHT BEAM CALIBRATION BLOCKS FOR BOLTING

(a) Block A Nomenclature

d = bolt diameter
D = calibration block diameter
Dh = flat-bottom hole diameter
D/
4
l = bolt length
L = calibration block length
l/ Lh = flat-bottom hole length
8

“bolt” refers to the material

L to be examined (bolting)
(typ)
(b) Block B

D l/
(typ) 4

Lh
(typ)

(c) Block C

Dh
(typ) l/
2

Diameter of Bolting Material to be Calibration Block Flat-Bottom Hole Calibration Flat-Bottom

Examined (d ) Diameter (D ) Diameter (Dh ) Block Hole Depth
Designation (Lh )
Up to 1 in. (25 mm) d ±d⁄4 1
⁄16 in. (1.5 mm)
Over 1 in. (25 mm) to 2 in. (50 mm) d ±d⁄4 1
⁄8 in. (3 mm) A 1.5 in. (38 mm)
Over 2 in. (50 mm) to 3 in. (75 mm) d ±d⁄4 3
⁄16 in. (5 mm) B 0.5 in. (13 mm)
Over 3 in. (75 mm) to 4 in. (100 mm) d ±d⁄4 5
⁄16 in. (8 mm) C 0.5 in. (13 mm)
3
Over 4 in. (100 mm) d ± 1 in. (25 mm) ⁄8 in. (10 mm)

GENERAL NOTE: A tolerance of ±5% may be applied.

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ARTICLE 5 2010 SECTION V

T-562.4 Contact Wedges. The same contact wedges to the correction in the examination record. All recorded indi-
be used during the examination shall be used for cali- cations since the last valid calibration or calibration check
bration. shall be reexamined and their values shall be changed on
the data sheets or re-recorded.
T-562.5 Instrument Controls. Any control, which
affects instrument linearity (e.g., filters, reject, or clipping), T-563.3.2 Sensitivity Settings. If any sensitivity set-
shall be in the same position for calibration, calibration ting has changed by more than 20% or 2 dB of its amplitude,
checks, instrument linearity checks, and examination. correct the sensitivity calibration and note the correction
in the examination record. If the sensitivity setting has
T-562.6 Temperature. For contact examination, the decreased, all data sheets since the last valid calibration
temperature differential between the calibration block and or calibration check shall be marked void and the area
examination surfaces shall be within 25°F (14°C). For covered by the voided data shall be reexamined. If the
immersion examination, the couplant temperature for cali- sensitivity setting has increased, all recorded indications
bration shall be within 25°F (14°C) of the couplant temper- since the last valid calibration or calibration check shall
ature for examination. be reexamined and their values shall be changed on the
data sheets or re-recorded.
T-563 Calibration Confirmation
T-563.1 System Changes. When any part of the exami- T-564 Casting Calibration for Supplementary
nation system is changed, a calibration check shall be made Angle Beam Examinations
on the calibration block to verify that distance range points For supplementary angle-beam examinations, the instru-
and sensitivity setting(s) satisfy the requirements of ment gain shall be adjusted during calibration such that
T-563.3. the indication from the side-drilled hole producing the
T-563.2 Calibration Checks. A calibration check on highest amplitude is 80% ±5% of full screen height. This
at least one of the reflectors in the calibration block or a shall be the primary reference level.
check using a simulator shall be performed at the comple-
tion of each examination or series of similar examinations,
and when examination personnel (except for automated T-570 EXAMINATION
equipment) are changed. The distance range and sensitivity T-571 Examination of Product Forms
values recorded shall satisfy the requirements of T-563.3. T-571.1 Plate. Plate shall be examined in accordance
with SA-435/SA-435M, SA-577/SA-577M, SA-578/SA-
NOTE: Interim calibration checks between the required initial calibration
578M, or SB-548, as applicable, except as amended by
and the final calibration check may be performed. The decision to perform
interim calibration checks should be based on ultrasonic instrument stabil- the requirements elsewhere in this Article.
ity (analog vs. digital), the risk of having to conduct reexaminations, and
T-571.2 Forgings and Bars
the benefit of not performing interim calibration checks.
(a) Forgings and bars shall be examined in accordance
T-563.2.1 Simulator Checks. Any simulator checks with SA-388/SA-388M or SA-745/SA-745M, as applica-
that are used shall be correlated with the original calibration ble, except as amended by the requirements elsewhere in
on the calibration block during the original calibration. this Article.
The simulator checks may use different types of calibration (b) All forgings and bars shall be examined by the
reflectors or blocks (such as IIW) and/or electronic simula- straight-beam examination technique.
tion. However, the simulation used shall be identifiable on (c) In addition to T-571.2(b), ring forgings and other
the calibration sheet(s). The simulator check shall be made hollow forgings shall also be examined by the angle-beam
on the entire examination system. The entire system does examination technique in two circumferential directions,
not have to be checked in one operation; however, for its unless wall thickness or geometric configuration makes
check, the search unit shall be connected to the ultrasonic angle-beam examination impractical.
instrument and checked against a calibration reflector. (d) In addition to T-571.2(b) and (c), ring forgings made
Accuracy of the simulator checks shall be confirmed, using to fine grain melting practices and used for vessel shell
the calibration block, every three months or prior to first sections shall be also examined by the angle-beam exami-
use thereafter. nation technique in two axial directions.
T-563.3 Confirmation Acceptance Values (e) Immersion techniques may be used.
T-563.3.1 Distance Range Points. If any distance T-571.3 Tubular Products. Tubular products shall be
range point has moved on the sweep line by more than examined in accordance with SE-213 or SE-273, as appli-
10% of the distance reading or 5% of full sweep (whichever cable, except as amended by the requirements elsewhere
is greater), correct the distance range calibration and note in this Article.

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T-571.4 Castings. Castings shall be examined in accor- T-573.3 Inservice Examination of Cladding. Inser-
dance with SA-609/SA-609M, except as amended by the vice examination of cladding, excluding weld metal over-
requirements elsewhere in this Article. lay cladding, shall be in accordance with SA-578/SA-
(a) For straight-beam examinations, the sensitivity com- 578M.
pensation in paragraph 8.3 of SA-609/SA-609M shall not
be used.
T-574 Thickness Measurement
(b) A supplementary angle-beam examination shall be
performed on castings or areas of castings where a back Thickness measurement shall be performed in accor-
reflection cannot be maintained during straight-beam dance with SE-797, except as amended by the requirements
examination, or where the angle between the front and elsewhere in this Article.
back surfaces of the casting exceeds 15 deg.
T-571.5 Bolting Material. Bolting material shall be
examined in accordance with SA-388/SA-388M, except as T-580 EVALUATION
amended by the requirements elsewhere in this Article. For examinations using DAC calibrations, any imperfec-
(a) Bolting material shall be examined radially prior to tion with an indication amplitude in excess of 20% of DAC
threading. Sensitivity shall be established using the indica- shall be investigated to the extent that it can be evaluated
tion from the side of the hole in calibration block A at in terms of the acceptance criteria of the referencing Code
radial metal paths of D⁄4 and 3D⁄4. The instrument gain shall Section.
be adjusted such that the indication from the D⁄4 or 3D⁄4 hole
(whichever has the highest indication amplitude) is 80%
±5% of full screen height (FSH). This shall be the primary T-590 DOCUMENTATION
reference level. A distance-amplitude correction (DAC)
T-591 Recording Indications
curve shall be established using the indications from the
D
⁄4 and 3D⁄4 holes and shall be extended to cover the full T-591.1 Non-Rejectable Indications. Non-rejectable
diameter of the material being examined. indications shall be recorded as specified by the referencing
(b) Bolting material shall be examined axially from both Code Section.
end surfaces, either before or after threading. The instru- T-591.2 Rejectable Indications. Rejectable indications
ment gain shall be adjusted such that the indication from shall be recorded. As a minimum, the type of indication
the flat-bottom hole producing the highest indication ampli- (i.e., crack, lamination, inclusion, etc.), location, and extent
tude, is 80% ±5% FSH. This shall be the primary reference (i.e., length) shall be recorded.
level. A DAC curve shall be established using the indica-
tions from the three flat-bottom holes and shall be extended
to cover the full length of the material being examined. If T-592 Examination Records
any flat-bottom hole indication amplitude is less than 20% For each ultrasonic examination, the following informa-
FSH, construct two DAC lines using calibration blocks A tion shall be recorded:
and B, and calibration blocks B and C and record the gain (a) procedure identification and revision
setting necessary to adjust the highest indication amplitude (b) ultrasonic instrument identification (including man-
for each DAC to 80% ±5% FSH. ufacturer’s serial number)
(c) Immersion techniques may be used. (c) search unit(s) identification (including manufactur-
er’s serial number, frequency, and size)
T-572 Examination of Pumps and Valves (d) beam angle(s) used
Ultrasonic examination of pumps and valves shall be in (e) couplant used, brand name or type
accordance with Mandatory Appendix I. (f) search unit cable(s) used, type and length
(g) special equipment, when used (search units, wedges,
shoes, automatic scanning equipment, recording equip-
T-573 Inservice Examination ment, etc.)
T-573.1 Nozzle Inner Radius and Inner Corner (h) computerized program identification and revision,
Region. Inservice examination of nozzle inner radii and when used
inner corner regions shall be in accordance with Mandatory (i) calibration block identification
Appendix II. (j) simulation block(s) and electronic simulator(s) iden-
T-573.2 Inservice Examination of Bolting. Inservice tification, when used
examination of bolting shall be in accordance with Manda- (k) instrument reference level gain and, if used, damping
tory Appendix IV. and reject setting(s)

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ARTICLE 5 2010 SECTION V

(l) calibration data [including reference reflector(s), (r) examination personnel identity and, when required
indication amplitude(s), and distance reading(s)] by referencing Code Section, qualification level
(m) data correlating simulation block(s) and electronic (s) date of examination
Items T-592(b) through (m) may be included in a sepa-
simulator(s), when used, with initial calibration
rate calibration record provided the calibration record iden-
(n) identification of material or volume scanned tification is included in the examination record.
(o) surface(s) from which examination was conducted,
T-593 Report
including surface condition
A report of the examinations shall be made. The report
(p) map or record of rejectable indications detected or shall include those records indicated in T-591 and T-592.
areas cleared The report shall be filed and maintained in accordance with
(q) areas of restricted access or inaccessible areas the referencing Code Section.

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ARTICLE 5
MANDATORY APPENDICES

APPENDIX I — ULTRASONIC II-531.1 General. The general calibration block

EXAMINATION OF PUMPS AND requirements of Article 4, T-434.1 shall apply.
VALVES II-531.2 Mockups. If sound beams only pass through
I-510 SCOPE nozzle forgings during examinations, nozzle mockups may
be nozzle forgings, or segments of forgings, fixed in struc-
This Appendix describes supplementary requirements to
tures as required to simulate adjacent vessel surfaces. If
Article 5 for ultrasonic examination of welds or base mate-
sound beams pass through nozzle-to-shell welds during
rial repairs, or both, in pumps and valves.
examinations, nozzle mockups shall contain nozzle welds
and shell components of sufficient size to permit cali-
I-530 EQUIPMENT bration.
I-531 Calibration Blocks II-531.3 Thickness. The calibration block shall equal or
Calibration blocks for pumps and valves shall be in exceed the maximum component thickness to be examined.
accordance with Article 4, Nonmandatory Appendix J. II-531.4 Reflectors. The calibration block shall contain (10)
a minimum of three notches within the examination vol-
ume. Alternatively, induced or embedded cracks may be
I-560 CALIBRATION
used in lieu of notches, which may also be employed for
I-561 System Calibration demonstration of sizing capabilities when required by the
System calibration shall be in accordance with Article referencing Code Section. Notches or cracks shall meet
4, T-463 exclusive of T-463.1.1. the following requirements:
(a) Notches or cracks shall be distributed radially in
two zones with at least one notch or crack in each zone.
I-570 EXAMINATION Zone 1 ranges between 0 deg and 180 deg (±45 deg) and
The examination shall be in accordance with Article 4, Zone 2 is the remaining two quadrants, centered on the
T-470. nozzle’s axis.
(b) Notches or cracks shall be placed within the nozzle
inner radii examination volume and oriented parallel to the
APPENDIX II — INSERVICE axial plane of the nozzle; the orientation tolerance is ±2 deg.
EXAMINATION OF NOZZLE INSIDE (c) Notch or crack lengths shall be 1 in. (25 mm) maxi-
CORNER RADIUS AND INNER mum. Nominal notch widths shall be 1⁄16 in. (1.5 mm).
CORNER REGIONS (d) Notch or crack depths, measured from the nozzle
inside surface, shall be:
II-510 SCOPE
(1) Reflector No. 1 – 0.20 in. to 0.35 in. (5 mm to
This Appendix describes supplementary requirements to 9 mm)
Article 5 for inservice examination of nozzle inside corner (2) Reflector No. 2 – 0.35 in. to 0.55 in. (9 mm to
radius and inner corner regions. 14 mm)
(3) Reflector No. 3 – 0.55 in. to 0.75 in. (14 mm to
II-530 EQUIPMENT 19 mm)
II-531 Calibration Blocks
II-560 CALIBRATION
Calibration blocks shall be full-scale or partial-section
(mockup) nozzles, which are sufficient to contain the maxi- II-561 System Calibration
mum sound beam path, examination volume, and calibra- System calibration shall be in accordance with Article
tion reflectors. 4, T-463 exclusive of T-463.1.1.

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ARTICLE 5 2010 SECTION V

II-570 EXAMINATION reflector at the same sound path distance in the basic cali-
bration block.
The general examination requirements of Article 4,
T-471 shall apply. Automated Ultrasonic Examinations (AUT): a technique
of ultrasonic examination performed with equipment and
search units that are mechanically mounted and guided,
remotely operated, and motor-controlled (driven) without
APPENDIX III — GLOSSARY OF adjustments by the technician. The equipment used to per-
TERMS FOR ULTRASONIC form the examinations is capable of recording the ultra-
EXAMINATION sonic response data, including the scanning positions, by
means of integral encoding devices such that imaging of
III-510 SCOPE
the acquired data can be performed.
This Mandatory Appendix is used for the purpose of axial direction: direction of sound beam parallel to com-
establishing standard terms and definition of terms related ponent’s major axis.
to Ultrasonic Examination. calibration: correlation of the ultrasonic system
response(s) with calibration reflector(s).
calibration reflector: a reflector with a dimensioned sur-
III-520 GENERAL REQUIREMENTS face which is used to provide an accurately reproducible
(a) The Standard Terminology for Nondestructive reference level.
Examinations (ASTM E 1316) has been adopted by the circumferential direction: direction of sound beam per-
Committee as SE-1316. pendicular to (cylindrical) component’s major axis.
(b) SE-1316 Section I provides the definitions of terms clipping: see reject.
listed in III-530(a). computerized imaging: computer processed display or
(c) For general terms, such as Interpretation, Flaw, Dis- analysis and display of ultrasonic data to provide two- or
continuity, Evaluation, etc., refer to Article 1, Man-datory three-dimensional images of reflectors.
Appendix I. CRT: cathode ray tube.
(d) Paragraph III-540(b) provides a list of terms and
Distance Amplitude Correction (DAC) curve: see dis-
definitions, which are in addition to SE-1316 and are Code
tance amplitude response curve.
specific.
D-scan: an ultrasonic data presentation which provides
an end view of the specimen indicating the approximate
III-540 MISCELLANEOUS REQUIREMENTS width (as detected per scan) of reflectors and their relative
positions.
(a) The following SE-1316 terms are used in conjunc- dynamic calibration: calibration that is conducted with
tion with this Article or other referencing Article or Appen- the search unit in motion, usually at the same speed and
dix: A-scan; amplitude; angle beam; attenuation; direction of the actual test examination.
attenuator; B-scan presentation; back reflection; base line; electric simulator: an electronic device that enables cor-
beam spread; C-scan; contact testing; couplant; damping, relation of ultrasonic system response initially obtained
search unit; decibel (dB); distance amplitude response
employing the basic calibration block.
curve; dual search unit; echo; frequency (inspection); fre-
examination coverage: two-directional search unit beam
quency (pulse repetition); holography (acoustic); immer-
coverage, both parallel and perpendicular to the weld axis,
sion testing; indication; initial pulse; interface; linearity
(amplitude); linearity (time or distance); longitudinal of the volume specified by the referencing Code Section.
wave; loss of back reflection; mode; noise; pulse; pulse Perpendicularly oriented search unit beams are directed
echo method; pulse repetition rate; range; reference block; from both sides of the weld, when possible, with the
reflector; reject (suppression); resolution; scanning; angle(s) selected to be appropriate for the configuration
search unit; sensitivity; shear wave; signal-to-noise ratio; being examined.
straight beam; sweep; test surface; through transmission examination system: a system that includes the ultrasonic
technique; transducer; ultrasonic; vee path; video presen- instrument, search unit cable, and search unit.
tation; wedge. Manual Ultrasonic Examinations (MUT) or Encoded
(b) The following Code terms are used in conjunction Manual Ultrasonic Examinations (EMUT): a technique of
with this Article or other referencing Article or Appendix: ultrasonic examination performed with search units that
alternative reflector: a reflector, other than the specified are manipulated by hand without the aid of any mechanical
reflector, whose ultrasonic response has been adjusted to guidance system. Manual techniques may be encoded such
be equal to or greater than the response from the specified that imaging of the acquired data can be performed.

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multiple back reflections: in ultrasonic straight beam back-wall signal: sound wave that travels between the
examination, successive reflections from the back and front two transducers with a longitudinal velocity that reflects
surfaces of the material. off the materials back surface.
piezoelectric element: crystal or polycrystal materials D-scan (non-parallel scan): scan that shows the data
which when mechanically deformed, produce electrical collected when scanning the transducer pair perpendicular
charges, and conversely, when intermittently charged, will to the direction of the sound beam along a weld.
deform and produce mechanical vibrations. diffracted signals: diffracted waves from the upper and
primary reference response (level): the ultrasonic lower tips of flaws resulting from its interaction with the
response from the basic calibration reflector at the specified incident sound wave.
sound path distance, electronically adjusted to a specified free-run: recording a set of data without moving the
percentage of the full screen height. search-units.
refraction: the angular change in direction of the ultra- lateral wave: sound wave that travels directly between
sonic beam as it passes obliquely from one medium to the transducers with a longitudinal velocity just below the
another, in which the waves have a different velocity. surface of the material.
ringing time: the time that the mechanical vibrations of time-of-flight: the time it takes for a sound wave to travel
a piezoelectric element continue after the electrical pulse from the transmitting transducer to the flaw, and then to
has stopped. the receiving transducer.
scan plan: a documented examination strategy that pro- (d) The following definitions are used in conjunction
vides a standardized and repeatable methodology for weld with Article 4, Mandatory Appendix III:
examinations. The scan plan displays cross-sectional joint back-wall echo: a specular reflection from the back-wall
geometry, extent of coverage, clad or overlay (if present), of the component being examined.
Heat Affected Zone (HAZ) extent, search unit size(s) and diffraction: when a wave front direction has been
frequency(ies), beam plots of all angles used, search unit(s) changed by an obstacle or other in-homogeneity in a
position in relation to the weld centerline [Probe Center medium, other than by reflection or refraction.
Spacing (PCS) in the case of Time of Flight Diffraction free run: taking data, without the movement of the
(TOFD)], and if applicable, zonal coverage overlap. probes (e.g., held stationary), of the lateral wave and back-
scanning surface: see test surface. wall reflection to check system software output.
Semi-Automated Ultrasonic Examinations (SAUT): a lateral wave: a compression wave that travels by the
technique of ultrasonic examination performed with equip- most direct route from the transmitting probe to the receiv-
ment and search units that are mechanically mounted and ing probe in a TOFD configuration.
guided, manually assisted (driven), and which may be man- nonparallel or longitudinal scan: a scan whereby the
ually adjusted by the technician. The equipment used to probe pair motion is perpendicular to the ultrasonic beam
perform the examinations is capable of recording the ultra- (e.g., parallel to the weld axis).
sonic response data, including the scanning positions, by parallel or transverse scan: a scan whereby the probe
means of integral encoding devices such that imaging of pair motion is parallel to the ultrasonic beam (e.g., perpen-
the acquired data can be performed. dicular to the weld axis).
probe center spacing (PCS): the distance between the
simulation block: a reference block or other item in
marked exit points of a pair of TOFD probes for a specific
addition to the basic calibration block that enables correla-
application.
tion of ultrasonic system response initially obtained when
TOFD display: a cross-sectional grayscale view of the
using the basic calibration block.
weld formed by the stacking of the digitized incremental
SAFT-UT: Synthetic Aperture Focusing Technique for
A-scan data. The two types of scans (parallel and non-
ultrasonic testing.
parallel) are differentiated from each other by calling one
static calibration: calibration for examination wherein
a B-scan and the other a D-scan. Currently there is no
the search unit is positioned on a calibration block so that standardized terminology for these scans and they may be
the pertinent reflectors can be identified and the instrumen- interchanged by various manufacturers (e.g., one calling
tation adjusted accordingly. the scan parallel to the weld axis a B-scan and another a
(c) The following definitions are used in conjunction D-scan).
with Article 4, Appendix L:
acoustic pulse: the duration of time between the start
and end of the signal when the amplitude reaches 10% of APPENDIX IV — INSERVICE
the maximum amplitude. EXAMINATION OF BOLTS
B-scan (parallel scan): scan that shows the data col- IV-510 SCOPE
lected when scanning the transducer pair in the direction This Appendix describes supplementary requirements to
of the sound beam transversely across a weld. Article 5 for inservice examination of bolts.

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ARTICLE 5 2010 SECTION V

IV-530 EQUIPMENT As an alternative to straight-cut notches, other notches

(e.g., circular cut) may be used provided the area of the
IV-531 Calibration Blocks
notch does not exceed the area of the applicable straight-
Calibration blocks shall be full-scale or partial-section cut notches required by this paragraph.
bolts, which are sufficient to contain the maximum sound
beam path and area of interest, and to demonstrate the
IV-560 CALIBRATION
scanning technique.
IV-561 DAC Calibration
IV-531.1 Material. The calibration block shall be of A DAC curve shall be established using the calibration
the same material specification, product form, and surface reflectors in IV-531.2. The sound beam shall be directed
finish as the bolt(s) to be examined. toward the calibration reflector that yields the maximum
IV-531.2 Reflectors. Calibration reflectors shall be response, and the instrument shall be set to obtain an 80%
straight-cut notches. A minimum of two notches shall be of full screen height indication. This shall be the primary
machined in the calibration standard, located at the mini- reference level. The search unit shall then be manipulated,
without changing instrument settings, to obtain the maxi-
mum and maximum metal paths, except that notches need
mum responses from the other calibration reflector(s) to
not be located closer than one bolt diameter from either
generate a DAC curve. The calibration shall establish both
end. Notch depths shall be as follows:
the sweep range calibration and the distance amplitude
Bolt Size Notch Depth* correction.
Less than 2 in. (50 mm) 1 thread depth
5
2 in. (50 mm) and greater, but ⁄64in. (2.0 mm)
less than 3 in. (75 mm) IV-570 EXAMINATION
3
3 in. (75 mm) and greater ⁄32 in. (2.5 mm) IV-571 General Examination Requirements
The general examination requirements of Article 4,
*
Measured from bottom of thread root to bottom of notch. T-471 shall apply.

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