ASTM E1211-07
(Practice)Standard Practice for Leak Detection and Location Using Surface-Mounted Acoustic Emission Sensors
Standard Practice for Leak Detection and Location Using Surface-Mounted Acoustic Emission Sensors
SIGNIFICANCE AND USE
Leakage of gas or liquid from a pressurized system, whether through a crack, orifice, seal break, or other opening, may involve turbulent or cavitational flow, which generates acoustic energy in both the external atmosphere and the system pressure boundary. Acoustic energy transmitted through the pressure boundary can be detected at a distance by using a suitable acoustic emission sensor.
With proper selection of frequency passband, sensitivity to leak signals can be maximized by eliminating background noise. At low frequencies, generally below 100 kHz, it is possible for a leak to excite mechanical resonances within the structure that may enhance the acoustic signals used to detect leakage.
This practice is not intended to provide a quantitative measure of leak rates.
SCOPE
1.1 This practice describes a passive method for detecting and locating the steady state source of gas and liquid leaking out of a pressurized system. The method employs surface-mounted acoustic emission sensors (for non-contact sensors see Test Method E 1002), or sensors attached to the system via acoustic waveguides (for additional information, see Terminology E 1316), and may be used for continuous in-service monitoring and hydrotest monitoring of piping and pressure vessel systems. High sensitivities may be achieved, although the values obtainable depend on sensor spacing, background noise level, system pressure, and type of leak.
1.2 The values stated in inch-pound units are to be regarded as the standard. SI units are provided for information only.
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:E1211–07
Standard Practice for
Leak Detection and Location Using Surface-Mounted
1
Acoustic Emission Sensors
This standard is issued under the fixed designation E1211; 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.
3
1. Scope 2.2 ASNT Documents:
SNT-TC-1A Recommended Practice for Nondestructive
1.1 This practice describes a passive method for detecting
Testing Personnel Qualification and Certification
and locating the steady state source of gas and liquid leaking
ANSI/ASNT CP-189 Standard for Qualification and Certi-
out of a pressurized system. The method employs surface-
fication of Nondestructive Testing Personnel
mounted acoustic emission sensors (for non-contact sensors
2.3 AIA Document:
see Test Method E1002), or sensors attached to the system via
NAS 410 Certification and Qualification of Nondestructive
acoustic waveguides (for additional information, seeTerminol-
4
Testing Personnel
ogy E1316), and may be used for continuous in-service
monitoring and hydrotest monitoring of piping and pressure
3. Summary of Practice
vessel systems. High sensitivities may be achieved, although
3.1 This practice requires the use of contact sensors, ampli-
the values obtainable depend on sensor spacing, background
fier electronics, and equipment to measure their output signal
noise level, system pressure, and type of leak.
levels. The sensors may be mounted before or during the
1.2 The values stated in inch-pound units are to be regarded
examination period and are normally left in place once
as the standard. SI units are provided for information only.
mounted rather than being moved from point to point.
1.3 This standard does not purport to address all of the
3.2 Detection of a steady-state leak is based on detection of
safety concerns, if any, associated with its use. It is the
the continuous, broadband signal generated by the leak flow.
responsibility of the user of this standard to establish appro-
Signal detection is accomplished through measurement of
priate safety and health practices and determine the applica-
some input signal level, such as its root-mean-square (RMS)
bility of regulatory limitations prior to use.
amplitude or average signal level.
2. Referenced Documents 3.3 The simplest leak test procedure involves only detection
2
of leaks, treating each sensor channel individually. A more
2.1 ASTM Standards:
complex examination requires processing the signal levels
E543 Specification for Agencies Performing Nondestruc-
from two or more sensors together to allow computation of the
tive Testing
approximate leak location, based on the principle that the leak
E650 Guide for Mounting Piezoelectric Acoustic Emission
signal amplitude decreases as a function of distance from the
Sensors
source.
E750 Practice for CharacterizingAcoustic Emission Instru-
mentation
4. Significance and Use
E976 Guide for Determining the Reproducibility ofAcous-
4.1 Leakage of gas or liquid from a pressurized system,
tic Emission Sensor Response
whether through a crack, orifice, seal break, or other opening,
E1002 Test Method for Leaks Using Ultrasonics
may involve turbulent or cavitational flow, which generates
E1316 Terminology for Nondestructive Examinations
acousticenergyinboththeexternalatmosphereandthesystem
E2374 Guide for Acoustic Emission System Performance
pressure boundary. Acoustic energy transmitted through the
Verification
pressure boundary can be detected at a distance by using a
suitable acoustic emission sensor.
1
This practice is under the jurisdiction of ASTM Committee E07 on Nonde-
4.2 With proper selection of frequency passband, sensitivity
structive Testing and is the direct responsibility of Subcommittee E07.04 on
to leak signals can be maximized by eliminating background
Acoustic Emission Method.
Current edition approved July 1, 2007. Published July 2007. Originally approved
in 1987. Last previous edition approved in 2002 as E1211 - 02. DOI: 10.1520/
E1211-07.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or AvailablefromAmericanSocietyforNondestructiveTesting(ASNT),P.O.Box
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org.
4
Standards volume information, refer to the standard’s Document Summary page on Available fromAerospace IndustriesAssociation ofAmerica, Inc. (AIA), 1000
the ASTM website. WilsonBlvd.,Suite1700,Arlington,VA22209-3928,http://www.aia-aerospace.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.