Standard Specification for Straight-Beam Ultrasonic Examination of Plain and Clad Steel Plates for Special Applications

SCOPE
1.1 This specification covers the procedure and acceptance standards for straight-beam, pulse-echo, ultrasonic examination of rolled carbon and alloy plain and clad steel plates, 3/8 in. [10 mm] in thickness and over, for special applications. The method will detect internal discontinuities parallel to the rolled surfaces. Three levels of acceptance standards are provided. Supplementary requirements are provided for examination of clad plate and for alternative procedures.
1.2 Individuals performing examinations in accordance with this specification shall be qualified and certified in accordance with the requirements of the latest edition of ASNT SNT-TC-1A or an equivalent accepted standard. An equivalent standard is one which covers the qualification and certification of ultrasonic nondestructive examination candidates and which is acceptable to the purchaser.
1.3 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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ASTM A578/A578M-96(2001) - Standard Specification for Straight-Beam Ultrasonic Examination of Plain and Clad Steel Plates for Special Applications
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: A 578/A578M – 96 (Reapproved 2001)
Standard Specification for
Straight-Beam Ultrasonic Examination of Plain and Clad
Steel Plates for Special Applications
This standard is issued under the fixed designationA578/A578M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope Steel-Clad Plate, Sheet, and Strip
2 A 264 Specification for Stainless Chromium-Nickel Steel-
1.1 This specification covers the procedure and acceptance
Clad Plate, Sheet, and Strip
standards for straight-beam, pulse-echo, ultrasonic examina-
A 265 Specification for Nickel and Nickel-BaseAlloy-Clad
tionofrolledcarbonandalloyplainandcladsteelplates, ⁄8 in.
Steel Plate
[10 mm] in thickness and over, for special applications. The
2.2 ANSI Standard:
method will detect internal discontinuities parallel to the rolled
B 46.1 Surface Texture
surfaces. Three levels of acceptance standards are provided.
2.3 ASNT Standard:
Supplementary requirements are provided for examination of
SNT-TC-1A
clad plate and for alternative procedures.
1.2 Individualsperformingexaminationsinaccordancewith
3. Ordering Information
this specification shall be qualified and certified in accordance
3.1 The inquiry and order shall indicate the following:
with the requirements of the latest edition of ASNT SNT-
3.1.1 Acceptance level requirements (Sections 7, 8, and 9).
TC-1A or an equivalent accepted standard. An equivalent
Acceptance Level B shall apply unless otherwise agreed to by
standard is one which covers the qualification and certification
purchaser and manufacturer.
of ultrasonic nondestructive examination candidates and which
3.1.2 Any additions to the provisions of this specification as
is acceptable to the purchaser.
prescribed in 5.2, 13.1, and Section 10.
1.3 The values stated in either inch-pound units or SI units
3.1.3 Supplementary requirements, if any.
are to be regarded separately as standard. Within the text, the
SI units are shown in brackets. The values stated in each
4. Apparatus
system are not exact equivalents; therefore, each system must
4.1 The amplitude linearity shall be checked by positioning
be used independently of the other. Combining values from the
the transducer over the depth resolution notch in the IIW or
two systems may result in nonconformance with the specifi-
similar block so that the signal from the notch is approximately
cation.
30 % of the screen height, and the signal from one of the back
1.4 This standard does not purport to address all of the
surfaces is approximately 60 % of the screen height (two times
safety concerns, if any, associated with its use. It is the
the height of the signal from the notch).Acurve is then plotted
responsibility of the user of this standard to establish appro-
showing the deviations from the above established 2:1 ratio
priate safety and health practices and determine the applica-
that occurs as the amplitude of the signal from the notch is
bility of regulatory limitations prior to use.
raised in increments of one scale division until the back
2. Referenced Documents reflection signal reaches full scale, and then is lowered in
increments of one scale division until the notch signal reaches
2.1 ASTM Standards:
one scale division. At each increment the ratio of the two
A 263 Specification for Corrosion-Resisting Chromium
signals is determined. The ratios are plotted on the graph at the
position corresponding to the larger signal. Between the limits
of 20 and 80 % of the screen height, the ratio shall be within
This specification is under the jurisdiction of ASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee
A01.11 on Steel Plates for Boilers and Pressure Vessels. Annual Book of ASTM Standards, Vol 01.03.
Current edition approved March 10, 2001. Published November 1996. Originally Available from American National Standards Institute, 11 W. 42nd St., 13th
published as A 578 – 67 T. Last previous edition A 578/A 578M – 92. floor, New York, NY 10036.
2 5
For ASME Boiler and Pressure Vessel Code applications, see related Specifi- Available from American Society for Nondestructive Testing, 1711 Arlingate
cation SA-578/SA-578M in Section II of that Code. Plaza, Columbus, OH 43228.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
A 578/A578M – 96 (2001)
NOTE 1—Indications occurring midway between the initial pulse and
10 % of 2:1. Instrument settings used during inspection shall
the first back reflection may cause a second reflection at the location of the
not cause variation outside the 10 % limits established above.
first back reflection. When this condition is observed it shall be investi-
4.2 The transducer shall be 1 or 1 ⁄8 in. [25 or 30 mm] in
gated additionally by use of multiple back reflections.
diameter or 1 in. [25 mm] square.
6.3 Where grid scanning is performed and recordable con-
4.3 Other search units may be used for evaluating and
ditionsasin6.1and6.2aredetectedalongagivengridline,the
pinpointing indications.
entire surface area of the squares adjacent to this indication
5. Procedure
shall be scanned. Where parallel path scanning is performed
and recordable conditions as in 6.1 and 6.2 are detected, the
5.1 Perform the inspection in an area free of operations that
entire surface area ofa9by 9-in. [225 by 225-mm] square
interfere with proper performance of the test.
centered on this indication shall be scanned. The true bound-
5.2 Unless otherwise specified, make the ultrasonic exami-
aries where these conditions exist shall be established in either
nation on either major surface of the plate.
method by the following technique: Move the transducer away
5.3 The plate surface shall be sufficiently clean and smooth
from the center of the discontinuity until the height of the back
to maintain a first reflection from the opposite side of the plate
reflection and discontinuity indications are equal. Mark the
at least 50 % of full scale during scanning. This may involve
plate at a point equivalent to the center of the transducer.
suitable means of scale removal at the manufacturer’s option.
Repeat the operation to establish the boundary.
Condition local rough surfaces by grinding. Restore any
specified identification which is removed when grinding to
7. Acceptance Standard—Level A
achieve proper surface smoothness.
7.1 Any area where one or more discontinuities produce a
5.4 Perform the test by one of the following methods: direct
continuous total loss of back reflection accompanied by con-
contact, immersion, or liquid column coupling. Use a suitable
tinuous indications on the same plane that cannot be encom-
couplant such as water, soluble oil, or glycerin. As a result of
passed within a circle whose diameter is 3 in. [75 mm] or ⁄2 of
the test by this method, the surface of plates may be expected
the plate thickness, whichever is greater, is unacceptable.
to have a residue of oil or rust or both.
5.5 Anominal test frequency of 2 ⁄4 MHz is recommended.
8. Acceptance Standards—Level B
When testing plates less than ⁄4 in. [20 mm] thick a frequency
8.1 Any area where one or more discontinuities produce a
of 5 MHz may be necessary. Thickness, grain size or micro-
continuous total loss of back reflection accompanied by con-
structure of the material and nature of the equipment or method
tinuous indications on the same plane that cannot be encom-
may require a higher or lower test frequency. Use the trans-
passed within a circle whose diameter is 3 in. [75 mm] or ⁄2 of
ducers at their rated frequency.Aclean, easily interpreted trace
the plate thickness, whichever is greater, is unacceptable.
pattern should be produced during the examination.
8.2 In addition, two or more discontinuities smaller than
5.6 Scanning:
described in 8.1 shall be unacceptable unless separated by a
5.6.1 Scanning shall be along continuous perpendicular grid
minimum distance equal to the greatest diameter of the larger
lines on nominal 9-in. [225-mm] centers, or at the option of the
discontinuity or unless they may be collectively encompassed
manufacturer, shall be along continuous parallel paths, trans-
by the circle described in 8.1.
verse to the major plate axis, on nominal 4-in. [100-mm]
centers, or shall be along continuous parallel paths parallel to
9. Acceptance Standard—Level C
the major plate axis, on 3-in. [75-mm] or smaller centers.
9.1 Any area where one or more discontinuities produce a
Measure the lines from the center or one corner of the plate
continuous total loss of back reflection accompanied by con-
with an additional path within 2 in. [50 mm] of all edges of the
tinous indications on the same plane that cannot be encom-
plate on the searching surface.
passed within a 1-in. [25-mm] diameter circle is unacceptable.
5.6.2 Conduct the general scanning with an instrument
adjustment that will produce a first reflection from the opposite
10. Report
side of a sound area of the plate from 50 to 90 % of full scale.
10.1 Unless otherwise agreed to by the purchaser and the
Minor sensitivity adjustments may be made to accommodate
manufacturer, the manufacturer shall report the following data:
for surface roughness.
10.1.1 All recordable indications listed in Section 6 on a
5.6.3 When a discontinuity condition is observed during
sketch of the plate with sufficient data to relate the geometry
general scanning adjust the instrument to produce a first
and identity of the sketch to those of the plate.
reflection from the opposite side of a sound area of the plate of
10.1.2 Test parameters including: Make and model of in-
75 6 5 % of full scale. Maintain this instrument setting during
strument, test frequency, surface condition, transducer (type
evaluation of the discontinuity condition.
and frequency), and couplant.
6. Recording
10.1.3 Date of test.
6.1 Record all discontinuities causing complete loss of back
11. Inspection
reflection.
6.2 For plates ⁄4 in. [20 mm] thick and over, record all 11.1 The inspector representing the purchaser shall have
indicationswithamplitudesequaltoorgreaterthan50 %ofthe access at all times, while work on the contract of the purchaser
initial back reflection and accompanied by a 50 % loss of back is being performed, to all parts of the manufacturer’s works
reflection. that concern the ultrasonic testing of the material ordered. The
A 578/A578M – 96 (2001)
manufacturer shall afford the inspector all reasonable facilities 13. Marking
to satisfy him that the material is being furnished in accordance
13.1 Plates accepted according to this specification shall be
with this specification. All tests and inspections shall be made
identified by stenciling (stamping) “UT A 578—A” on one
at the place of manufacture prior to shipment, unless otherwise
corner for Level A, “UT A 578—B” for Level B, and “UT A
specified, and shall be conducted without interfering unneces-
578—C” for Level C. The supplement number shall be added
sarily with the manufacturer’s operations.
for each supplementary requirement ordered.
12. Rehearing
14. Keywords
12.1 The manufacturer reserves the right to discuss reject-
able ultrasonically tested plate with the purchaser with the 14.1 nondestructive testing; pressure containing parts; pres-
object of possible repair of the ultrasonically indicated defect sure vessel steels; steel plate for pressure vessel applications;
before rejection of the plate. steel plates; ultrasonic examinations
SUPPLEMENTARY REQUIREMENTS
These supplementary requirements shall apply only when individually specified by the purchaser.
When details of these requirements are not covered herein, they are subject to agreement between the
manufacturer and the purchaser.
S1. Scanning S6.2 Inspect the backing steel to Level B or, if specifically
requested by customer, to Level A or Level C.
S1.1 Scanning shall be continuous over 100 % of the plate
S6.3 The cladding shall be interpreted to be unbonded when
surface.
there is complete loss of back reflection accompanied by an
S2. Acceptance Standard echo indication from the plane of the interface of the clad and
backing steel.
S2.1 Any recordable condition listed in Section 6 that (1)is
S6.4 Unless otherwise specified, indications of unbond
continuous, (2) is on the same plane (within 5 % of the plate
determined in accordance with S 6.3 that cannot be encom-
thickness), and (3) cannot be encompassed by a 3-in. [75-mm]
passed within a 3-in. [75-mm] diameter circle shall be weld
diameter circle, is unacceptable. Two or more recordable
repaired subject to the requirements and limitations for the
conditions (see Section 5), that (1) are on the same plane
repair of defects in cladding of the appropriate material
(within 5 % of plate thickness), (2) individually can be
specification.
encompassed by a 3-in. [75-mm] diameter circle, (3) are
S6.5 ThissupplementaryrequirementisapplicabletoSpeci-
separated from each other by a distance less than the greatest
fications A 263, A 264, and A 265.
dimensionofthesmallerindication,and(4)collectivelycannot
be encompassed by a 3-in. [75-mm] diameter circle, are
S7. Examination of Integrally Bonded Clad Plate,
unacceptable.
Acceptance Level S 7
S2.2 An acceptance level more restrictive than Section 7 or
S7.1 The plate shall be examined from the clad surface
8 shall be used by agreement between the manufacturer and
using procedures and techniques according to this specification
purchaser.
except 100 % surface search is mandatory.
S3. Procedure
S7.2 Inspect the backing steel to Level B or, if specifically
requested by customer, to Level A or Level C.
S3.1 The manufacturer shall provide a written procedure in
S7.3 The cladding shall be interpreted to be unbonded when
accordance with this specification.
there is complete loss of back reflection accompanied by an
S4. Certification
echo indication from the plane of the interface of the clad and
backing steel.
S4.1 The manufacturer shall provide a written certification
S7.4 Unless otherwise specified, indications of unbond
of the ultrasonic test operator’s qualifications.
determined in accordance with S 7.3 that cannot be encom-
S5. Surface Finish
passed within a 1-in. [25-mm] diameter circle shall be weld
repaired subject to the requirements and limitations for the
S5.1 The surface finish of the plate shall be conditioned to
repair of defects in cladding of the appropriate material
...

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