ASTM A939-07(2012)
(Practice)Standard Practice for Ultrasonic Examination from Bored Surfaces of Cylindrical Forgings
Standard Practice for Ultrasonic Examination from Bored Surfaces of Cylindrical Forgings
SIGNIFICANCE AND USE
This practice shall be used when ultrasonic inspection from the bore surface is required by the order or specification for inspection purposes in which the acceptance of the forging is based on limitations of the number, amplitude, or location of discontinuities or a combination thereof, which leads to ultrasonic indications.
The acceptance criteria shall be stated clearly as order requirements.
This practice specifies dual search units, which depending on the angle, are sensitive only to 2 to 3 in. into the metal from the bore surface.
SCOPE
1.1 This practice covers a basic procedure of ultrasonically inspecting cylindrical forgings with bores from the bore surface.
1.2 This practice applies to the manual testing mode. It does not restrict the use of other testing modes, such as mechanized or automated.
1.3 This practice applies to cylindrical forgings having bore sizes equal to or greater than 2.5 in. (63.5 mm).
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.5 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.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: A939 − 07(Reapproved 2012)
Standard Practice for
Ultrasonic Examination from Bored Surfaces of Cylindrical
Forgings
This standard is issued under the fixed designation A939; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope inspect some small portions of the bore surface because of
chamfers at stepdowns and other local configurations.
1.1 This practice covers a basic procedure of ultrasonically
inspecting cylindrical forgings with bores from the bore 3.2 The bore ultrasonic inspection shall be performed after
surface. the final austenitizing and tempering heat treatment for me-
chanical properties of the forging, and may be performed either
1.2 This practice applies to the manual testing mode. It does
prior to or after any subsequent stress relieving heat treatment.
not restrict the use of other testing modes, such as mechanized
or automated. 3.3 The ultrasonic beam shall be introduced radially for
overall scanning.
1.3 This practice applies to cylindrical forgings having bore
sizes equal to or greater than 2.5 in. (63.5 mm). 3.4 Forgings may be tested either when stationary or while
rotated by means of a lathe or rollers.
1.4 The values stated in inch-pound units are to be regarded
as standard. The values given in parentheses are mathematical
3.5 To ensure complete coverage of the bore surface, the
conversions to SI units that are provided for information only search unit shall be indexed approximately 75 % of the
and are not considered standard.
transducer width with each pass of the search unit.
1.5 This standard does not purport to address all of the
3.6 Afrequency of 2 ⁄4 MHz shall be used unless additional
safety concerns, if any, associated with its use. It is the
transducer frequencies are specified by the purchaser.
responsibility of the user of this standard to establish appro-
3.7 The bore hole diameter and calibration hole(s) shall be
priate safety and health practices and determine the applica-
as specified on the purchaser’s drawing or order.
bility of regulatory limitations prior to use.
4. Pulsed Ultrasonic Reflection Equipment and
2. Significance and Use
Accessories
2.1 This practice shall be used when ultrasonic inspection
4.1 Electronic Apparatus—A pulse echo instrument permit-
from the bore surface is required by the order or specification
ting inspection frequencies of 1, 2.25, and 5 MHz is required.
for inspection purposes in which the acceptance of the forging
The accuracy of discontinuity amplitude analysis using this
is based on limitations of the number, amplitude, or location of
practice involves a knowledge of the true operating frequency
discontinuities or a combination thereof, which leads to ultra-
of the complete inspection system. One of the best ways to
sonic indications.
obtain the desired accuracy is by use of a tuned pulser and
2.2 The acceptance criteria shall be stated clearly as order
narrow band amplifier of known frequency response, with
requirements.
either a broad band transducer or a narrow band tuned
2.3 This practice specifies dual search units, which depend-
transducer of known and matching frequency. An equipment
ing on the angle, are sensitive only to 2 to 3 in. into the metal calibration plan that is acceptable to both the purchaser and the
from the bore surface.
supplier shall be available.
4.2 Amplifier—The amplifier and the cathode ray tube shall
3. General Requirements
provide linear response (within 65%)upto1 ⁄2 in. (38.1 mm)
3.1 As far as possible, the entire bore surface shall be
sweep to peak.An equipment calibration plan that is acceptable
subjected to ultrasonic inspection. It may be impossible to
to both the purchaser and the supplier shall be available.
4.3 Signal Attenuator—The instrument shall contain a cali-
This practice is under the jurisdiction of ASTM Committee A01 on Steel,
Stainless Steel and Related Alloys and is the direct responsibility of S
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.