ASTM D5503-94(2008)
(Practice)Standard Practice for Natural Gas Sample-Handling and Conditioning Systems for Pipeline Instrumentation (Withdrawn 2017)
Standard Practice for Natural Gas Sample-Handling and Conditioning Systems for Pipeline Instrumentation (Withdrawn 2017)
SIGNIFICANCE AND USE
A well-designed sample-handling and conditioning system is essential to the accuracy and reliability of pipeline instruments. Approximately 70 % of the problems encountered are associated with the sampling system.
SCOPE
1.1 This practice covers sample-handling and conditioning systems for typical pipeline monitoring instrumentation (gas chromatographs, moisture analyzers, and so forth). The selection of the sample-handling and conditioning system depends upon the operating conditions and stream composition.
1.2 This practice is intended for single-phase mixtures that vary in composition. A representative sample cannot be obtained from a two-phase stream.
1.3 The values stated in SI units are to regarded as standard. The values stated in English units are for information only.
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.
WITHDRAWN RATIONALE
Formerly under the jurisdiction of Committee D03 on Gaseous Fuels, this practice was withdrawn in January 2017 in accordance with section 10.6.3 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.
General Information
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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D5503 − 94 (Reapproved 2008)
Standard Practice for
Natural Gas Sample-Handling and Conditioning Systems for
Pipeline Instrumentation
This standard is issued under the fixed designation D5503; 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 3. Terminology
1.1 This practice covers sample-handling and conditioning 3.1 Definitions:
systems for typical pipeline monitoring instrumentation (gas 3.1.1 compressed natural gas—natural gas compressed to
chromatographs, moisture analyzers, and so forth). The selec- approximately 3600 psi.
tion of the sample-handling and conditioning system depends
3.1.2 density—mass per unit volume of the substance being
upon the operating conditions and stream composition.
considered.
1.2 This practice is intended for single-phase mixtures that
3.1.3 dew point—the temperature and pressure at which the
vary in composition. A representative sample cannot be ob-
first droplet of liquid forms from a vapor.
tained from a two-phase stream.
3.1.4 lag time—time required to transport the sample to the
1.3 The values stated in SI units are to regarded as standard.
analyzer.
The values stated in English units are for information only.
3.1.5 natural gas—mixture of low molecular weight hydro-
1.4 This standard does not purport to address all of the
carbons obtained from petroleum-bearing regions.
safety concerns, if any, associated with its use. It is the
3.1.6 sample probe—device to extract a representative
responsibility of the user of this standard to establish appro-
sample from the pipeline.
priate safety and health practices and determine the applica-
3.1.7 system turnaround time—the time required to trans-
bility of regulatory limitations prior to use.
port the sample to the analyzer and to measure the desired
components.
2. Referenced Documents
2.1 ASTM Standards:
4. Significance and Use
D1142 Test Method for Water Vapor Content of Gaseous
4.1 Awell-designed sample-handling and conditioning sys-
Fuels by Measurement of Dew-Point Temperature
tem is essential to the accuracy and reliability of pipeline
D3764 Practice forValidation of the Performance of Process
instruments.Approximately 70 % of the problems encountered
Stream Analyzer Systems
are associated with the sampling system.
2.2 Other Standards:
ANSI/API 2530 (AGA Report Number 3)
5. Selection of Sample-Handling and Conditioning
AGA Report Number 8
System
NACE Standard MR-01-75
5.1 The sample-handling and conditioning system must
extract a representative sample from a flowing pipeline, trans-
This practice is under the jurisdiction of ASTM Committee D03 on Gaseous
port the sample to the analyzer, condition the sample to be
Fuels and is the direct responsibility of Subcommittee D03.01 on Collection and
compatible with the analyzer, switch sample streams and
Measurement of Gaseous Samples.
calibration gases, transport excess sample to recovery (or
CurrenteditionapprovedDec.1,2008.PublishedJuly2009.Originallyapproved
disposal), and resist corrosion by the sample.
in 1994. Last previous edition approved in 2003 as D5503 – 94 (2003). DOI:
10.1520/D5503-94R08.
5.2 The sample probe should be located in a flowing
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
pipeline where the flow is fully developed (little turbulence)
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
and where the composition is representative. In areas of high
the ASTM website.
turbulence, the contaminates that normally flow along the
Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
bottom or the wall of the pipeline will form aerosols.
4th Floor, New York, NY 10036, http://www.ansi.org.
Available from American Gas Association, 1515 Wilson Blvd., Arlington, VA
5.3 The purpose of the sample probe is to extract a repre-
22209.
sentative sample by obtaining it near the center of the pipeline
Available from NACE International (NACE), 1440 South Creek Dr., Houston,
TX 77084-4906, http://www.nace.org. where changes in stream composition can be quickly detected.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5503 − 94 (2008)
5.3.1 Thetipinthesampleprobeshouldbepositionedinthe 6. Apparatus
center one third of the pipeline, away from the pipeline wall
6.1 The following are common components of a sample-
where large particles accumulate. 6
handling and conditioning system (see Refs (1) and (2) for
5.3.2 Theprobeshouldbeaminimumoffivepipediameters
more information).
from any device that could produce aerosols or significant
6.1.1 Ball valves, needle valves, and solenoid valves are
pressure drop.
typically used for stream switching, sample shutoff, calibration
gas introduction, or sample vent and bypass systems.
5.3.3 The sample probe should not be located within a
defined meter tube region (see ANSI/API 2530 AGA Report 6.1.2 Most pipeline samples require some filtering. Since all
filter elements eventually plug, they should be replaced on a
Number 3 and AGA Report Number 8 for more information).
regular maintenance schedule. There are several types of filter
5.3.4 The sample probe should be mounted vertically from
designs.
thetoponhorizontalpipelines.Thesampleprobeshouldnotbe
6.1.2.1 In-Line Filter—All of the sample passes through an
located on vertical pipelines.
in-line filter. The active filter elements are available in Teflon
5.4 The sampling-handling system must transport the
polypropylene, copolymer, or stainless steel. (See Fig. 1.)
sample to the analyzer and dispose of excess sample. Since the
6.1.2.2 Bypass Filter—Only a small portion of the sample
sampling point and the analyzer may be separated by some
passes through a bypass filter, while a majority of the sample
distance, the time required to transport the sample to the
passes across its surface keeping it clean. The active filter
analyzer can contribute significantly to the system turnaround
element is either a disposable cartridge or a reusable sintered
time.
metal element. (See Fig. 2.)
6.1.2.3 Cyclone Filter—The cyclone filter is a centrifugal
5.4.1 The analyzer should be located as close to the sam-
pling point as is practical to minimize the sample lag time. cleanup device.The sample enters at high velocity tangentially
to the wall of a cylindrical-shaped vessel with a conical-shaped
5.4.2 The sample-handling system should be equipped with
bottom.The centrifugal force developed by the spinning action
a full open ball valve and a particular filter.
of the gas as it follows the shape of the vessel forces particles
5.5 The sizing of the sample transport line will be influ-
and droplets to the wall where they are removed through the
enced by a number of factors:
vent flow. (See Fig. 3.)
5.5.1 The sample point pressure and the location of the
6.1.2.4 Coalescing Filter—Coalescers, also known as mem-
pressure reduction regulator. brane separators, are used to force finely divided liquid
droplets to combine into larger droplets so they can be
5.5.2 The acceptable lag time between the sample point and
separated by gravity. The design of the coalescer body forces
the analyzer.
the heavier phase out the bottom and the lighter phase out the
5.5.3 The requirements of the analyzer, such as flow rate,
top. The flow rates out the top and the bottom are critical for
pressure, and temperature for the analysis. For multistream
proper operation. (See Fig. 4.)
systems,thesamplelineandassociatedmanifoldtubingshould
(1) Since this process removes part of the sample, the
be flushed with sufficient sample to assure a representative
impact on sample composition must be considered.
sample of the selected stream.
5.5.4 The presence of sample-conditioning elements will
contribute to the lag time and must be considered in the
The boldface numbers in parentheses refer to the list of references at the end of
calculation of the minimum sample flow rate.
this practice.
5.5.4.1 Each element could be considered as an equivalent
length of sample line and added to the length of line from the
sample point to the analyzer.
5.5.4.2 The purge time of each element is calculated as the
time necessary for five volumes of sample to flow through the
element.
5.5.5 A vapor sample must be kept at least 10°C above the
hydrocarbon dew point temperature to prevent condensation of
thesample.Thesamplelineshouldbeheattracedandinsulated
when appropriate.
5.5.5.1 For compressed natural gas (CNG), the pressure
must be reduced in two stages to avoid condensation of liquids
caused by the Joule-Thompson effect. In a heated zone at
approximately 50°C, the pressure should be dropped to ap-
proximately10MPa(1500psig)andthentoasuitablepressure
for the analyzer. Any conditioning of the sample must be
completed in the heated zone.
5.5.5.2
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