ASTM E1814-14

Standard Practice for Computed Tomographic (CT) Examination of Castings

SIGNIFICANCE AND USE
4.1 CT may be performed on an object when it is in the as-cast, intermediate, or final machined condition. A CT examination can be used as a design tool to improve wax forms and moldings, establish process parameters, randomly check process control, perform final quality control (QC) examination for the acceptance or rejection of parts, and analyze failures and extend component lifetimes.  
4.2 The most common applications of CT for castings are for the following: locating and characterizing discontinuities, such as porosity, inclusions, cracks, and shrink; measuring as-cast part dimensions for comparison with design dimensions; and extracting dimensional measurements for reverse engineering.  
4.3 The extent to which a CT image reproduces an object or a feature within an object is dictated largely by the competing influences of spatial resolution, contrast discrimination, the specific geometry and material of the object itself, and artifacts of the imaging system. Operating parameters strike an overall balance between image quality, examination time, and cost.  
4.4 Artifacts are often the limiting factor in CT image quality. (See Practice E1570 for an in-depth discussion of artifacts.) Artifacts are reproducible features in an image that are not related to actual features in the object. Artifacts can be considered correlated noise because they form repeatable fixed patterns under given conditions yet carry no object information. For castings, it is imperative to recognize what is and is not an artifact since an artifact can obscure or masquerade as a discontinuity. Artifacts are most prevalent in castings with long straight edges or complex geometries, or both.
SCOPE
1.1 This practice covers a uniform procedure for the examination of castings by the computed tomography (CT) technique. The requirements expressed in this practice are intended to control the quality of the nondestructive examination by CT and are not intended for controlling the acceptability or quality of the castings. This practice implicitly suggests the use of penetrating radiation, specifically X rays and gamma rays.  
1.2 This practice provides a uniform procedure for a CT examination of castings for one or more of the following purposes:  
1.2.1 Examining for discontinuities, such as porosity, inclusions, cracks, and shrink;  
1.2.2 Performing metrological measurements and determining dimensional conformance; and  
1.2.3 Determining reverse engineering data, that is, creating computer-aided design (CAD) data files.  
1.3 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

• Status: Historical
• Publication Date: 31-May-2014
• ICS: 77.040.20 - Non-destructive testing of metals
• Technical Committee: E07 - Nondestructive Testing
• Drafting Committee: E07.01 - Radiology (X and Gamma) Method

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: E1814 − 14
Standard Practice for
1
Computed Tomographic (CT) Examination of Castings
This standard is issued under the fixed designation E1814; 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* E1695 Test Method for Measurement of Computed Tomog-
raphy (CT) System Performance
1.1 This practice covers a uniform procedure for the exami-
E1935 Test Method for Calibrating and Measuring CT
nation of castings by the computed tomography (CT) tech-
Density
nique.The requirements expressed in this practice are intended
E2339 Practice for Digital Imaging and Communication in
to control the quality of the nondestructive examination by CT
Nondestructive Evaluation (DICONDE)
and are not intended for controlling the acceptability or quality
E2767 Practice for Digital Imaging and Communication in
of the castings. This practice implicitly suggests the use of
Nondestructive Evaluation (DICONDE) for X-ray Com-
penetrating radiation, specifically X rays and gamma rays.
puted Tomography (CT) Test Methods
3
1.2 This practice provides a uniform procedure for a CT
2.2 ASNT Documents:
examination of castings for one or more of the following
SNT-TC-1A Recommended Practice for Personnel Qualifi-
purposes:
cation and Certification in Nondestructive Testing
1.2.1 Examining for discontinuities, such as porosity,
ANSI/ASNT CP-189 Standard for Personnel Qualification
inclusions, cracks, and shrink;
and Certification of Nondestructive Testing Personnel
1.2.2 Performing metrological measurements and determin- 4
2.3 Military Standards:
ing dimensional conformance; and
NAS 410 Certification and Qualification of Nondestructive
1.2.3 Determining reverse engineering data, that is, creating
Test Personnel
computer-aided design (CAD) data files.
3. Terminology
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.1 Definitions—Definitions of terms applicable to this
responsibility of the user of this standard to establish appro-
practice may be found in Terminology E1316 and Guide
priate safety and health practices and determine the applica-
E1441.
bility of regulatory limitations prior to use.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 fixturing—the mounting hardware used to place the
2. Referenced Documents
object in the CT system.
2
2.1 ASTM Standards:
3.2.2 scan plan—scan locations and the system configura-
E543 Specification for Agencies Performing Nondestructive
tion parameters for a specific part examination.
Testing
4. Significance and Use
E1316 Terminology for Nondestructive Examinations
E1441 Guide for Computed Tomography (CT) Imaging
4.1 CT may be performed on an object when it is in the
E1570 Practice for Computed Tomographic (CT) Examina-
as-cast, intermediate, or final machined condition. A CT
tion
examinationcanbeusedasadesigntooltoimprovewaxforms
E1672 Guide for Computed Tomography (CT) System Se-
and moldings, establish process parameters, randomly check
lection
process control, perform final quality control (QC) examina-
tion for the acceptance or rejection of parts, and analyze
failures and extend component lifetimes.
1
This practice is under the jurisdiction of ASTM Committee E07 on Nonde-
4.2 The most common applications of CT for castings are
structive Testing and is the direct responsibility of Subcommittee E07.01 on
for the following: locating and characterizing discontinuities,
Radiology (X and Gamma) Method.
Current edition approved June 1, 2014. Published June 2014. Originally
approved in 1996. Last previous edition approved in 2007 as E1814 - 96(2007).
3
DOI: 10.1520/E1814-14. AvailablefromAmericanSocietyforNondestructiveTesting(ASNT),P.O.Box
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org.
4
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,
Standards volume information, refer to the standard’s Document Summary page on Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http://
the ASTM website. assist.daps.dla.mil.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1814 − 14
such as porosity, inclusions, cracks, and shrink; measuring subsystem components. Guidance on the selection of sub-
as-cast part dimensions for comparison with design dimen-
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: E1814 − 96 (Reapproved 2007) E1814 − 14
Standard Practice for
1
Computed Tomographic (CT) Examination of Castings
This standard is issued under the fixed designation E1814; 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 Scope*
1.1 This practice covers a uniform procedure for the examination of castings by the computed tomography (CT) technique. The
requirements expressed in this practice are intended to control the quality of the nondestructive examination by CT and are not
intended for controlling the acceptability or quality of the castings. This practice implicitly suggests the use of penetrating
radiation, specifically X rays and gamma rays.
1.2 This practice provides a uniform procedure for a CT examination of castings for one or more of the following purposes:
1.2.1 Examining for discontinuities, such as porosity, inclusions, cracks, and shrink;
1.2.2 Performing metrological measurements and determining dimensional conformance; and
1.2.3 Determining reverse engineering data, that is, creating computer-aided design (CAD) data files.
1.3 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. For specific safety statements, see Section 7,NBS Handbook 114, and 21 CFR 1020.40 and
29 CFR 1910.96.
2. Referenced Documents
2
2.1 ASTM Standards:
E543 Specification for Agencies Performing Nondestructive Testing
E1316 Terminology for Nondestructive Examinations
E1441 Guide for Computed Tomography (CT) Imaging
E1570 Practice for Computed Tomographic (CT) Examination
E1672 Guide for Computed Tomography (CT) System Selection
E1695 Test Method for Measurement of Computed Tomography (CT) System Performance
E1935 Test Method for Calibrating and Measuring CT Density
E2339 Practice for Digital Imaging and Communication in Nondestructive Evaluation (DICONDE)
E2767 Practice for Digital Imaging and Communication in Nondestructive Evaluation (DICONDE) for X-ray Computed
Tomography (CT) Test Methods
3
2.2 ASNT Documents:
SNT-TC-1A Recommended Practice for Personnel Qualification and Certification in Nondestructive Testing
ANSI/ASNT CP-189 Standard for Personnel Qualification and Certification of Nondestructive Testing Personnel
4
2.3 Military Standards:
MIL-STD-410 Nondestructive Testing Personnel Qualification and Certification
NAS 410 Certification and Qualification of Nondestructive Test Personnel
5
2.4 Code of Federal Regulations:
21 CFR 1020.40 Safety Requirements of Cabinet X Ray Systems
29 CFR 1910.96 Ionizing Radiation
1
This practice is under the jurisdiction of ASTM Committee E07 on Nondestructive Testing and is the direct responsibility of Subcommittee E07.01 on Radiology (X and
Gamma) Method.
Current edition approved July 1, 2007June 1, 2014. Published July 2007June 2014. Originally approved in 1996. Last previous edition approved in 20022007 as
E1814 - 96(2002).(2007). DOI: 10.1520/E1814-96R07.10.1520/E1814-14.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Available from American Society for Nondestructive Testing (ASNT), P.O. Box 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org.
4
Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http://
www.dodssp.daps.mil.http://assist.daps.dla.mil.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
E1814 − 14
3. Terminology
3.1 Definitions—Definitions of terms applicable to this practice may be found in Terminology E1316 and Guide E1441.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 fixturing—the mounting hardware used to place the object in the CT system.
3.2.2 representative quality indicator (RQI)—a real part, or a fabrication of similar geometry in radiologically s
...