Standard Practices for Sampling Water-Formed Deposits

SIGNIFICANCE AND USE
5.1 The goal of sampling is to obtain for analysis a portion of the whole that is representative. The most critical factors are the selection of sampling areas and number of samples, the method used for sampling, and the maintenance of the integrity of the sample prior to analysis. Analysis of water-formed deposits should give valuable information concerning cycle system chemistry, component corrosion, erosion, the failure mechanism, the need for chemical cleaning, the method of chemical cleaning, localized cycle corrosion, boiler carryover, flow patterns in a turbine, and the rate of radiation build-up. Some sources of water-formed deposits are cycle corrosion products, make-up water contaminants, and condenser cooling water contaminants.
SCOPE
1.1 These practices cover the sampling of water-formed deposits for chemical, physical, biological, or radiological analysis. The practices cover both field and laboratory sampling. It also defines the various types of deposits. The following practices are included:    
Sections  
Practice A—Sampling Water-Formed Deposits From Tubing
of Steam Generators and Heat Exchangers  
8 to 10  
Practice B—Sampling Water-Formed Deposits From Steam
Turbines  
11 to 14  
1.2 The general procedures of selection and removal of deposits given here can be applied to a variety of surfaces that are subject to water-formed deposits. However, the investigator must resort to his individual experience and judgment in applying these procedures to his specific problem.  
1.3 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.  
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.See Section 7, 9.8, 9.8.4.6, and 9.14 for specific hazards statements.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D887 − 13 (Reapproved 2022)
Standard Practices for
Sampling Water-Formed Deposits
This standard is issued under the fixed designation D887; 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 2. Referenced Documents
2.1 ASTM Standards:
1.1 These practices cover the sampling of water-formed
D512 Test Methods for Chloride Ion In Water (Withdrawn
deposits for chemical, physical, biological, or radiological
2021)
analysis. The practices cover both field and laboratory sam-
pling. It also defines the various types of deposits. The D934 Practices for Identification of Crystalline Compounds
in Water-Formed Deposits By X-Ray Diffraction (With-
following practices are included:
drawn 2022)
Sections
Practice A—Sampling Water-Formed Deposits From Tubing 8to10 D1129 Terminology Relating to Water
of Steam Generators and Heat Exchangers
D1193 Specification for Reagent Water
Practice B—Sampling Water-Formed Deposits From Steam 11 to 14
D1245 Practice for Examination of Water-Formed Deposits
Turbines
by Chemical Microscopy
1.2 The general procedures of selection and removal of
D1293 Test Methods for pH of Water
deposits given here can be applied to a variety of surfaces that
D2331 Practices for Preparation and Preliminary Testing of
aresubjecttowater-formeddeposits.However,theinvestigator
Water-Formed Deposits
must resort to his individual experience and judgment in
D2332 Practice for Analysis of Water-Formed Deposits by
applying these procedures to his specific problem.
Wavelength-Dispersive X-Ray Fluorescence
1.3 The values stated in inch-pound units are to be regarded
D3483 TestMethodsforAccumulatedDepositioninaSteam
as standard. The values given in parentheses are mathematical
Generator Tube
conversions to SI units that are provided for information only
D4412 Test Methods for Sulfate-Reducing Bacteria inWater
and are not considered standard.
and Water-Formed Deposits
1.4 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 Definitions of Terms Specific to This Standard:
responsibility of the user of this standard to establish appro-
3.1.1 biological deposits, n—water-formed deposits of or-
priate safety, health, and environmental practices and deter-
ganisms or the products of their life processes.
mine the applicability of regulatory limitations prior to use.See
3.1.1.1 Discussion- The biological deposits may be com-
Section7,9.8,9.8.4.6,and9.14forspecifichazardsstatements.
posed of microscopic organisms, as in slimes, or of macro-
1.5 This international standard was developed in accor-
scopic types such as barnacles or mussels. Slimes are usually
dance with internationally recognized principles on standard-
composed of deposits of a gelatinous or filamentous nature.
ization established in the Decision on Principles for the
3.1.2 corrosion products, n—a result of chemical or electro-
Development of International Standards, Guides and Recom-
chemical reaction between a metal and its environment.
mendations issued by the World Trade Organization Technical
3.1.2.1 Discussion—A corrosion deposit resulting from the
Barriers to Trade (TBT) Committee.
action of water, such as rust, usually consists of insoluble
material deposited on or near the corroded area; corrosion
These practices are under the jurisdiction of ASTM Committee D19 on Water
and are the direct responsibility of Subcommittee D19.03 on Sampling Water and For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
On-Line Water Analysis, and Surveillance of Water. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved July 1, 2022. Published July 2022. Originally approved the ASTM website.
in 1946. Last previous edition approved in 2013 as D887 – 13. DOI: 10.1520/ The last approved version of this historical standard is referenced on
D0887-13R22. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D887 − 13 (2022)
products may, however, be deposited a considerable distance all reagents shall conform to the specifications of the Commit-
from the point at which the metal is undergoing attack. tee onAnalytical Reagents of theAmerican Chemical Society,
3.1.3 scale, n—a deposit formed from solution directly in where such specifications are available. Other grades may be
place upon a surface. used, provided it is first ascertained that the reagent is of
3.1.3.1 Discussion—Scale is a deposit that usually will sufficiently high purity to permit its use without lessening the
retain its physical shape when mechanical means are used to accuracy of analysis.
remove it from the surface on which it is deposited. Scale, 6.1.1 Purity of Water—Reference to water that is used for
which may or may not adhere to the underlying surface, is reagent preparation, rinsing or dilution shall be understood to
usually crystalline and dense, frequently laminated, and occa- mean water that conforms to the quantitative specifications of
sionally columnar in structure. Type III reagent water of Specification D1193.
3.1.4 sludge, n—a water-formed sedimentary deposit.
6.2 Materials:
3.1.4.1 Discussion—The water-formed sedimentary depos-
6.2.1 The highest purity material available should be used
its may include all suspended solids carried by the water and
for removing the deposit samples.
trace elements which were in solution in the water. Sludge
6.2.2 Filter Paper may contain water leachable contami-
usually does not cohere sufficiently to retain its physical shape
nants (chloride, fluoride, and sulfur) which can be removed by
when mechanical means are used to remove it from the surface
pretreatment prior to sampling.
on which it deposits, but it may be baked in place and be hard
6.2.3 Polyester Tape may contain impurities of antimony
and adherent.
and cadmium which must be considered during analysis.
3.1.5 water-formed deposits, n—any accumulation of in-
soluble material derived from water or formed by the reaction 7. Hazards
of water upon surfaces in contact with the water.
7.1 Warnings:
3.1.5.1 Discussion—Deposits formed from or by water in
7.1.1 Special safety precautions are necessary in using
all its phases may be further classified as scale, sludge,
acetoneonawipematerialforremovingwater-formeddeposits
corrosion products, or biological deposit. The overall compo-
(see 9.8.4.6).
sition of a deposit or some part of a deposit may be determined
7.1.2 Special handling precautions may be required for
by chemical or spectrographic analysis; the constituents actu-
working with water-formed deposits containing radioactive
ally present as chemical substances may be identified by
nuclides (see 9.14).
microscope or x-ray diffraction studies. Organisms may be
7.2 Cautions:
identified by microscopic or biological methods.
7.2.1 Extreme care must be taken not to damage the
3.2 Definitions—For definitions of other terms used in these
underlying surface when removing water-formed deposit
practices, refer to Definitions D1129.
samples from equipment in the field (see 9.8).
7.2.2 The selection of samples necessarily depends on the
4. Summary of Practices
experience and judgment of the investigator. The intended use
4.1 These practices describe the procedures to be used for
of the sample, the accessibility and type of the deposit, and the
sampling water-formed deposits in both the field and labora-
problemtobesolvedwillinfluencetheselectionofthesamples
tory from boiler tubes and turbine components. They give
and the sampling method.
guidelines on selecting tube and deposit samples for removal
7.2.3 The most desirable amount of deposit to be submitted
and specify the procedures for removing, handling, and ship-
as a sample is not specific. The amount of deposit should be
ping of samples.
consistent with the type of analysis to be performed.
7.2.4 The samples must be collected, packed, shipped, and
5. Significance and Use
manipulated prior to analysis in a manner that safeguards
5.1 The goal of sampling is to obtain for analysis a portion
against change in the particular constituents or properties to be
of the whole that is representative.The most critical factors are
examined.
the selection of sampling areas and number of samples, the
7.2.5 The selection of sampling areas and number of
methodusedforsampling,andthemaintenanceoftheintegrity
samples is best guided by a thorough investigation of the
of the sample prior to analysis. Analysis of water-formed
problem. Very often the removal of a number of samples will
deposits should give valuable information concerning cycle
result in more informative analytical data than would be
system chemistry, component corrosion, erosion, the failure
obtained from one composite sample representing the entire
mechanism, the need for chemical cleaning, the method of
mass of deposit.Atypical example is the sampling of deposits
chemical cleaning, localized cycle corrosion, boiler carryover,
from a steam turbine. Conversely, in the case of a tube failure
flow patterns in a turbine, and the rate of radiation build-up.
in a steam generator, a single sample from the affected area
Some sources of water-formed deposits are cycle corrosion
may suffice.
products, make-up water contaminants, and condenser cooling
water contaminants.
Reagent Chemicals, American Chemical Society Specifications, American
Chemical Society, Washington, DC. For suggestions on the testing of reagents not
6. Reagents and Materials listed by the American Chemical Society, see Analar Standards for Laboratory
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
6.1 Purity of Reagents—Reagent grade chemicals shall be
and National Formulary, U.S. Pharmaceutical Convention, Inc. (USPC), Rockville,
used in all cases. Unless otherwise indicated, it is intended that MD.
D887 − 13 (2022)
TABLE 1 Selection of Samples
7.2.6 Most deposits are sampled at least twice before being
submitted to chemical or physical tests. The gross sample is Tube 1 Tube 2
first collected from its point of formation in the field and then Principal Adjacent Adjacent
Area Area Tube1or
this sample is prepared for final examination in the laboratory.
Related
7.2.7 A representative sample is not an absolute prerequi-
Tube
site. The quantity of deposit that can be removed is often
Preferred selection procedure X X X
limited. In such cases, it is better to submit a single mixed Alternative selection procedure 1 X X
Alternative selection procedure 2 X
sample (composite) and to describe how the sample was
Alternative selection procedure 3 X
obtained. For radiological analysis all samples should be
Alternative selection procedure 4 X
checked for activity levels before preparing a composite since
wide variations in radioactive content may occur in samples of
similar appearance and chemical composition.
7.2.8 It is good practice for deposits to be taken and
9.1.1 Preferred Selection Procedure—Select one or more
analyzed every time a turbine is opened for repairs or inspec-
separate tube samples containing the area of failure, heaviest
tion. Deposit history can then supplement chemical records of
deposition,orprincipleconcern(primaryarea)andincludeany
a unit, and deposit chemistry of units with and without
adjacent or closely related areas of these tube samples that
corrosion and other problems can be compared. Enough
might contain deposits significantly different from the primary
information on deposits has been published(1,2) that a com-
area.Also, one or more tube samples is selected from adjacent
parison between different types of boilers and different water
rows or other related areas that might contain deposits signifi-
treatments, as well as an assessment of deposit corrosiveness,
cantly different from the primary area.
are possible. It has been a general experience that about 0.2 %
9.1.2 AlternativeSelectionProcedure1—Selectoneormore
of a corrosive impurity, such as chloride, in a deposit, is a
separate tube samples containing the area of failure, heaviest
division between corrosive and noncorrosive deposits.
deposition,orprincipleconcern(primaryarea)andincludeany
7.2.9 Deposits taken after a turbine is open do not exactly
adjacent or closely related areas of these tube samples that
represent chemical composition of deposits in an operating
might contain deposits significantly different from the primary
turbine. Chemical thermodynamic data on steam additives and
area. Use this procedure when it is impractical to remove the
impurities,suchasvaporpressuresofsolutions,ionization,and
samples from adjacent rows or other related areas or when it is
volatility data are needed to reconstruct chemistry of environ-
improbable that the information gained by such sampling will
ment during operation.
justify the additional work involved.
7.2.10 Typical changes which occur after the hot turbine is
9.1.3 AlternativeSelectionProcedure2—Selectoneormore
shut down and air is admitted are: (1) reactions with oxygen
separate tube samples containing the area of failure, heaviest
and carbon dioxide, (2) drying of some deposits and water
deposition, or principle concern (primary area). Use this
absorption by others, (3) leaching and recrystallization where
procedure when only the tube section containing the primary
moisture is allowed to condense, and (4) formation of iron
area can be removed or when it is impractical to remove
hydroxide and hematite.
adjacentorcloselyrelatedareas,ortubesamplesfromadjacent
rows or other related areas, or when it is improbable that the
PRACTICE A—SAMPLING WATER-FORMED
information gained by such sampling will justify the additional
DEPOSITS FROM TUBING OF STEAM
work involved.
GENERATORS AND HEAT EXCHANGERS
9.1.4 AlternativeSelectionProcedure3—Selectoneormore
8. Scope
tube samples containing an area adjacent or closely related to
the primary area. Use this procedure only when it is not
8.1 This practice covers the sampling of water-formed
possible to obtain a tube section containing the primary area.
deposits from tubing of steam generators and heat exchangers.
9.1.5 Alternat
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