ASTM C1617-19

Standard Practice for Quantitative Accelerated Laboratory Evaluation of Extraction Solutions Containing Ions Leached from Thermal Insulation on Aqueous Corrosion of Metals

SIGNIFICANCE AND USE
5.1 Results from this accelerated corrosion test shall not be considered as an indicator of the useful life of the metal equipment. Many factors need consideration for applicability to specific circumstances. Refer to Guide C1696 and Practice G31 for additional information.  
5.2 Corrosion associated with insulation is an important concern for insulation manufacturers, specification writers, designers, contractors, users and operators of the equipment. Some material specifications contain test methods (or reference test methods contained in other material specifications), for use in evaluating the insulation with regard to the corrosion of steel, copper, and aluminum. In some cases these tests are not applicable or effective and have not been evaluated for precision and bias.  
5.3 A properly selected, installed, and maintained insulation system will reduce the corrosion that often occurs on an un-insulated structure. However, when the protective weather-resistant covering of an insulation system fails, the conditions for the aqueous environment necessary for corrosion under insulation (CUI) often develop. It is possible the insulation contains, collects, or concentrates corrosive agents, or a combination thereof, often found in industrial and coastal environments. If water is not present, these electrolytes cannot migrate to the metal surface. The electrochemical reaction resulting in the aqueous corrosion of metal surfaces cannot take place in the absence of water and electrolytes. Additional environmental factors contributing to increased corrosion rates are oxygen, and elevated-temperature (near boiling point).  
5.4 Chlorides and other corrosive ions are common to many environments. The primary corrosion preventative is to protect insulation and metal from contamination and moisture. Insulation covers, jackets, and metal coating of various kinds are often used to prevent water infiltration and contact with the metal.  
5.5 This procedure can be used to eval...
SCOPE
1.1 This practice covers procedures for a quantitative accelerated laboratory evaluation of the influence of extraction solutions containing ions leached from thermal insulation on the aqueous corrosion of metals. The primary intent of the practice is for use with thermal insulation and associated materials that contribute to, or alternatively inhibit, the aqueous corrosion of different types and grades of metals due to soluble ions that are leached by water from within the insulation. The quantitative evaluation criteria are Mass Loss Corrosion Rate (MLCR) expressed in mils per year determined from the weight loss due to corrosion of exposed metal coupons after they are cleaned.  
1.2 This practice cannot cover all possible field conditions that contribute to aqueous corrosion. The intent is to provide an accelerated means to obtain a non-subjective numeric value for judging the potential contribution to the corrosion of metals that can come from ions contained in thermal insulation materials or other experimental solutions. The calculated numeric value is the mass loss corrosion rate. This calculation is based on general corrosion spread equally over the test duration and the exposed area of the experimental cells created for the test. Corrosion found in field situations and this accelerated test also involves pitting and edge effects and the rate changes over time.  
1.3 The insulation extraction solutions prepared for use in the test can be altered by the addition of corrosive ions to the solutions to simulate contamination from an external source. Ions expected to provide corrosion inhibition can be added to investigate their inhibitory effect.  
1.4 Prepared laboratory ionic solutions are used as reference solutions and controls, to provide a means of calibration and comparison.2  
1.5 Other liquids can be tested for their potential corrosiveness including cooling tower water, boiler feed, and chemical stocks. ...

General Information

• Status: Published
• Publication Date: 30-Apr-2019
• ICS: 77.060 - Corrosion of metals
• Technical Committee: C16 - Thermal Insulation
• Drafting Committee: C16.31 - Chemical and Physical Properties

Relations

• Replaces: ASTM C1617-18a - Standard Practice for Quantitative Accelerated Laboratory Evaluation of Extraction Solutions Containing Ions Leached from Thermal Insulation on Aqueous Corrosion of Metals
• Effective Date: 01-May-2019
• Refers: ASTM A105/A105M-24 - Standard Specification for Carbon Steel Forgings for Piping Applications
• Effective Date: 15-Apr-2024
• Refers: ASTM C168-24 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 15-Apr-2024
• Refers: ASTM C739-24 - Standard Specification for Cellulosic Fiber Loose-Fill Thermal Insulation
• Effective Date: 01-Mar-2024
• Refers: ASTM A53/A53M-24 - Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless
• Effective Date: 01-Mar-2024
• Refers: ASTM G16-13(2019) - Standard Guide for Applying Statistics to Analysis of Corrosion Data
• Effective Date: 15-Feb-2019
• Refers: ASTM C168-18 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 15-Apr-2018
• Refers: ASTM C168-17 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 01-Jun-2017
• Refers: ASTM C1696-16 - Standard Guide for Industrial Thermal Insulation Systems
• Effective Date: 01-Mar-2016
• Refers: ASTM C168-15a - Standard Terminology Relating to Thermal Insulation
• Effective Date: 15-Oct-2015
• Refers: ASTM C518-15 - Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus
• Effective Date: 01-Sep-2015
• Refers: ASTM C1696-15 - Standard Guide for Industrial Thermal Insulation Systems
• Effective Date: 01-Sep-2015
• Refers: ASTM C168-15 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 01-Jun-2015
• Refers: ASTM C1696-14a - Standard Guide for Industrial Thermal Insulation Systems
• Effective Date: 01-Sep-2014
• Refers: ASTM C1696-14ae1 - Standard Guide for Industrial Thermal Insulation Systems
• Effective Date: 01-Sep-2014

Overview

ASTM C1617-19 is the Standard Practice developed by ASTM International for conducting quantitative accelerated laboratory evaluations of extraction solutions containing ions leached from thermal insulation materials, focusing on their effects on the aqueous corrosion of metals. The primary objective is to provide a reliable, non-subjective, and quantitative method for assessing the corrosion potential caused by soluble ions extracted from insulation products and related materials. This standard is critical for insulation manufacturers, material specifiers, asset owners, and maintenance professionals interested in minimizing corrosion under insulation (CUI) in industrial, commercial, and residential applications.

Key Topics

• Quantitative Evaluation: Utilizes the Mass Loss Corrosion Rate (MLCR), measured in mils per year, to quantify corrosion caused by exposure to extraction solutions from thermal insulation.
• Relevance to Multiple Metals: Can test various metal types and grades such as mild steel, stainless steel, copper, and aluminum using prepared metal coupons.
• Simulation of Field Conditions: While not a direct prediction of service life, the accelerated test provides comparable values for corrosion potential using standard laboratory procedures.
• Testing Variability: The method allows modification of the extraction solution, including the addition of corrosive or inhibiting ions, to simulate contamination or investigate corrosion inhibitors.
• Reference Solutions and Controls: Laboratory-prepared ionic solutions serve as controls for calibration and comparison, ensuring consistency and reliability in results.
• Evaluation of Accessories: Suitable for analyzing insulation-related materials such as jackets, adhesives, cements, and binders.
• Applicability to Non-Insulation Liquids: The procedure can also be adapted to test other liquids, such as cooling tower water or boiler feedwater, for their corrosive potential.

Applications

• Material Selection for Corrosion Prevention: Enables manufacturers and engineers to make informed decisions about insulation materials by assessing their tendency to leach corrosive ions that accelerate metal degradation.
• Corrosion Inhibitor Research: Provides a laboratory framework to test new additives and inhibitors incorporated into insulation products, supporting product innovation and improved performance.
• Compliance and Quality Assurance: Assists in verifying that insulation products meet ASTM and other regulatory standards regarding corrosion control when in contact with metal piping, vessels, or equipment.
• Maintenance Planning: Offers asset owners and facility operators a tool to identify potential risks of CUI and prioritize areas for routine inspection, repair, or replacement.
• Design & Specification: Assists specification writers and consultants in developing requirements for construction, maintenance, and refurbishment projects to ensure system longevity and integrity.
• Insulation System Evaluation: Helps evaluate not only base insulation products but also the performance of surface treatments, coatings, or assembly techniques aimed at reducing corrosion risk.

Related Standards

• ASTM C1696 - Guide for Industrial Thermal Insulation Systems
• ASTM G31 - Guide for Laboratory Immersion Corrosion Testing of Metals
• ASTM C871 - Test Methods for Chemical Analysis of Thermal Insulation Materials for Leachable Chloride, Fluoride, Silicate, and Sodium Ions
• ASTM C692 - Test Method for Evaluating the Influence of Thermal Insulations on External Stress Corrosion Cracking Tendency of Austenitic Stainless Steel
• ASTM G1 - Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens
• ASTM G16 - Guide for Applying Statistics to Analysis of Corrosion Data
• ASTM C518, C665, C739, C795 - Specifications relevant to thermal insulation products and their performance
• ASTM D609 - Practice for Preparing Steel Panels for Testing Coatings

By referencing ASTM C1617-19, professionals ensure a systematic approach to evaluating and mitigating the risk of corrosion aggravated by ionic contaminants leached from insulation. This helps safeguard valuable infrastructure, optimize maintenance costs, and enhance operational safety across industrial and commercial facilities.

Standards Content (Sample)

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: C1617 − 19
Standard Practice for
Quantitative Accelerated Laboratory Evaluation of
Extraction Solutions Containing Ions Leached from Thermal
Insulation on Aqueous Corrosion of Metals
This standard is issued under the fixed designation C1617; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.4 Preparedlaboratoryionicsolutionsareusedasreference
solutions and controls, to provide a means of calibration and
1.1 This practice covers procedures for a quantitative accel-
comparison.
erated laboratory evaluation of the influence of extraction
1.5 Other liquids can be tested for their potential corrosive-
solutions containing ions leached from thermal insulation on
ness including cooling tower water, boiler feed, and chemical
the aqueous corrosion of metals. The primary intent of the
stocks. Added chemical inhibitors or protective coatings ap-
practice is for use with thermal insulation and associated
plied to the metal can also be evaluated using the general
materialsthatcontributeto,oralternativelyinhibit,theaqueous
guidelines of the practice.
corrosionofdifferenttypesandgradesofmetalsduetosoluble
ions that are leached by water from within the insulation. The
1.6 Thevaluesstatedininch-poundunitsaretoberegarded
quantitative evaluation criteria are Mass Loss Corrosion Rate
as standard. The values given in parentheses are mathematical
(MLCR) expressed in mils per year determined from the
conversions to SI units that are provided for information only
weight loss due to corrosion of exposed metal coupons after
and are not considered standard.
they are cleaned.
1.7 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
1.2 This practice cannot cover all possible field conditions
responsibility of the user of this standard to establish appro-
thatcontributetoaqueouscorrosion.Theintentistoprovidean
priate safety, health, and environmental practices and deter-
acceleratedmeanstoobtainanon-subjectivenumericvaluefor
mine the applicability of regulatory limitations prior to use.
judging the potential contribution to the corrosion of metals
1.8 This international standard was developed in accor-
that can come from ions contained in thermal insulation
dance with internationally recognized principles on standard-
materials or other experimental solutions. The calculated
ization established in the Decision on Principles for the
numeric value is the mass loss corrosion rate. This calculation
Development of International Standards, Guides and Recom-
is based on general corrosion spread equally over the test
mendations issued by the World Trade Organization Technical
durationandtheexposedareaoftheexperimentalcellscreated
Barriers to Trade (TBT) Committee.
for the test. Corrosion found in field situations and this
accelerated test also involves pitting and edge effects and the
2. Referenced Documents
rate changes over time.
2.1 ASTM Standards:
1.3 The insulation extraction solutions prepared for use in
A53/A53MSpecification for Pipe, Steel, Black and Hot-
the test can be altered by the addition of corrosive ions to the
Dipped, Zinc-Coated, Welded and Seamless
solutions to simulate contamination from an external source.
Ions expected to provide corrosion inhibition can be added to
investigate their inhibitory effect.
The Uncertainty Test data have been moved to Appendix X4 because they are
based on data obtained using laboratory fabricated old style test coupons. The
precision and bias section, using the current practice of purchased test coupons,
This practice is under the jurisdiction of ASTM Committee C16 on Thermal replaces this uncertainty data. The Uncertainty Test data is preserved (for historical
InsulationandisthedirectresponsibilityofSubcommitteeC16.31onChemicaland purposes).
Physical Properties. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2019. Published June 2019. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 2005. Last previous edition approved in 2018 as C1617–18a. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/C1617-19. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1617 − 19
A105/A105MSpecification for Carbon Steel Forgings for the same time as the insulation extraction solutions. No other
Piping Applications comparisons shall be made.
C168Terminology Relating to Thermal Insulation
5. Significance and Use
C518Test Method for Steady-State Thermal Transmission
5.1 Results from this accelerated corrosion test shall not be
Properties by Means of the Heat Flow Meter Apparatus
considered as an indicator of the useful life of the metal
C665SpecificationforMineral-FiberBlanketThermalInsu-
equipment. Many factors need consideration for applicability
lation for Light Frame Construction and Manufactured
to specific circumstances. Refer to Guide C1696 and Practice
Housing
G31 for additional information.
C692Test Method for Evaluating the Influence of Thermal
Insulations on External Stress Corrosion Cracking Ten-
5.2 Corrosion associated with insulation is an important
dency of Austenitic Stainless Steel
concern for insulation manufacturers, specification writers,
C739Specification for Cellulosic Fiber Loose-Fill Thermal
designers, contractors, users and operators of the equipment.
Insulation
Somematerialspecificationscontaintestmethods(orreference
C795Specification for Thermal Insulation for Use in Con-
testmethodscontainedinothermaterialspecifications),foruse
tact with Austenitic Stainless Steel
in evaluating the insulation with regard to the corrosion of
C871Test Methods for ChemicalAnalysis of Thermal Insu-
steel, copper, and aluminum. In some cases these tests are not
lationMaterialsforLeachableChloride,Fluoride,Silicate,
applicable or effective and have not been evaluated for preci-
and Sodium Ions
sion and bias.
C1696Guide for Industrial Thermal Insulation Systems
5.3 Aproperlyselected,installed,andmaintainedinsulation
D609Practice for Preparation of Cold-Rolled Steel Panels
system will reduce the corrosion that often occurs on an
for Testing Paint, Varnish, Conversion Coatings, and
un-insulated structure. However, when the protective weather-
Related Coating Products
resistant covering of an insulation system fails, the conditions
G1Practice for Preparing, Cleaning, and Evaluating Corro-
for the aqueous environment necessary for corrosion under
sion Test Specimens
insulation (CUI) often develop. It is possible the insulation
G16Guide for Applying Statistics to Analysis of Corrosion
contains, collects, or concentrates corrosive agents, or a com-
Data
bination thereof, often found in industrial and coastal environ-
G31Guide for Laboratory Immersion Corrosion Testing of
ments.Ifwaterisnotpresent,theseelectrolytescannotmigrate
Metals
to the metal surface. The electrochemical reaction resulting in
G46Guide for Examination and Evaluation of Pitting Cor-
the aqueous corrosion of metal surfaces cannot take place in
rosion
the absence of water and electrolytes.Additional environmen-
talfactorscontributingtoincreasedcorrosionratesareoxygen,
3. Terminology
and elevated-temperature (near boiling point).
3.1 Definitions: Refer to Terminology C168 for definitions
5.4 Chloridesandothercorrosiveionsarecommontomany
relating to insulation.
environments.The primary corrosion preventative is to protect
insulation and metal from contamination and moisture. Insu-
4. Summary of Practice
lation covers, jackets, and metal coating of various kinds are
often used to prevent water infiltration and contact with the
4.1 The practice uses controlled amounts of test solutions
metal.
delivereddripwiseontoadefinedareaofsmallflatcouponsof
selected test metals for the purpose of producing, comparing,
5.5 This procedure can be used to evaluate all types of
and measuring the corrosion that occurs on the metals due to thermal insulation and fireproofing materials (industrial,
the exposure.
commercial, residential, cryogenic, fire-resistive, insulating
cement) manufactured using inorganic or organic materials,
4.2 The test is conducted at elevated temperatures, greatly
facedorunfaced,forwhichafilteredextractionsolutioncanbe
accelerating the corrosion in comparison with corrosion at
obtained.
room temperature. The heat makes the solution evaporate
5.6 This procedure can be used with all metal types for
quickly, allowing an air (oxygen) interface and making thou-
which a coupon can be prepared such as mild steel, stainless
sands of wet-dry-wet cycles possible in a short time.
steel, copper, or aluminum. Other metals (copper, aluminum)
4.3 Quantitative measurements of corrosion are determined
will need different times, reference solutions and cleaning
fromtheweightchange(loss)duetothecorrosionofthetested
practices. It shall not be interpreted that the steel procedures
coupons. Reference tests prepared with known concentrations
work for everything.When procedures are developed for other
of solutions that are conducive to the corrosion of the tested
metals they will be balloted for inclusion in the document.
metal are compared with water solutions containing ions
5.7 This procedure can also be applicable to insulation
extracted from insulation samples. Calculations of MLCR in
accessories including jacketing, covers, adhesives, cements,
mils-per-year (MPY) made using the methods of Practice G1
and binders associated with insulation and insulation products.
are recorded as the quantitative measurement. The measure-
ments are used to determine compliance with the applicable 5.8 Heattreatmentoftheinsulation(asrecommendedbythe
ASTM material specifications on a pass/fail basis when com- manufacturer up to the maximum potential exposure tempera-
pared to the corrosion reference solutions that were tested at ture) can be used to simulate possible conditions of use.
C1617 − 19
5.9 Adhesives can be tested by first drying followed by 6.10 Bottles,plastic1Lorequivalent,toindividuallysupply
water extraction or by applying a known quantity of the test each test specimen with test liquid.
adhesive to a test piece of insulation and then extracting.
6.11 Nominal 1-in. Pipe Size – PVC Class 200 Irrigation
5 3
5.10 Insulating cements can be tested by casting a slab,
Pipe (Thin Wall),1 ⁄16-in.(3.33cm)OD;1 ⁄16-in.(3.02cm)ID
drying, and extracting or by using the uncured insulating
by 1.25-in. (3.18 cm) lengths.
cement powder for extraction.
6.12 High Temperature Grease or Oil, for use as heat
5.11 Referencetestspreparedwithvariousconcentrationsof
transfer medium.
solutionsthatareconducivetothecorrosionofthetestedmetal
1 1
6.13 RubberO-Ring,1 ⁄4-in.(3.18cm)ID,1 ⁄2-in.(3.81cm)
serve as comparative criteria. Solutions containing chloride,
OD, ⁄8-in. (0.32 cm)thick.
sodium hydroxide, various acids (sulfuric, hydrochloric, nitric,
and citric acid), as well as “blank” tests using only de-ionized
6.14 Silicone Sealant, 100 % Silicone sealant.
water and tap water are used.
6.15 Plastic Straw, ⁄8-in. (0.32 cm) drink stirring straw
5.12 Research can be done on insulation that has been
(“swizzle stick”) .
specially formulated to inhibit corrosion in the presence of
corrosive ions through modifications in basic composition or 6.16 Cleaning Apparatus and Solutions,forthecarbonsteel
incorporationofcertainchemicaladditives.Corrosiveionscan coupons, Hydrochloric acid diluted 1 part to 3 parts water,
also be added to the insulation extraction solutions to deter- razor widget, sodium bicarbonate (baking soda) solution for
mine the effectiveness of any inhibitors present.
neutralizer, xylene, water paper or cloth towels, Wet Laid,
Nonwoven Fiberglass Facing ⁄16 in. thick – works well as a
5.13 Protective surface treatments and coatings of different
sacrificial scrubbing pad with the diluted HCL to clean and
types and thickness can be applied to the metal coupons and
polish the coupons.
compared using various corrosive liquids.
6.17 Hand-Held Magnifier, or 10 to 30× binocular
5.14 Several sets of tests are recommended because of the
microscope, or both.
number of factors that affect corrosion.An average of the tests
and the standard deviation between the test results are used on
6.18 Filter, 0.45 micron filter paper.
the data. Much of the corrosion literature recommends a
minimumofthreespecimensforeverytest.ConsultGuideG16
7. Reagents and Materials
foradditionalstatisticalmethodstoapplytothecorrosiondata.
7.1 Distilled or De-Ionized Water, containing less than 0.1
ppmchlorideions.Somede-ionizedandreverseosmosiswater
6. Apparatus
have been found not to be pure enough. This water is used to
6.1 Thetestapparatusmustbehousedinareasonablyclean
make the test solutions and reference solutions. The “zero
and non-dusty environment to avoid any effects of contami-
chloride” water test reference solution results are expected to
nants.
be only slightly higher than the cleaning blank result.
6.2 Heated Temperature Controlled Flat Hot Plate (see
7.2 Metal Test Coupons, meeting the composition require-
Appendix X1)—A 1-ft (30.5-cm) square or circular plate that
ments of applicable ASTM Specification for Mild Steel,
hasuniformtemperatureacrossthesurfaceprovidestheheated
Stainless Steel, Copper, or Aluminum. Mill certificates of
environment. See Appendix X1 for construct design and
chemical composition and mechanical properties are required.
sources of assembled systems. Larger plates for testing more
7.2.1 Some researchers will want to maintain traceability to
coupons are not excluded.
the metals used in other C16 corrosion procedures. Specifica-
6.3 Peristaltic Pump (see Appendix X1)—A multi-channel
tion C739 uses cold rolled, low carbon (<0.30%) commercial
peristaltic pump with individual cassettes and silicone tubes is
quality shim steel. Specification C665 uses cold rolled, low
recommended to supply 250 (610) mL/day to each specimen.
carbon, quarter hard, temper No. 3, strip steel. It is possible
Pump rates must be well controlled.
other metal grades meeting Specification A53/A53M, Specifi-
6.4 Silicone Rubber Tubing (see Appendix X1), to deliver cation A105/A105M, and other common ferrous steel specifi-
fluid to the test coupons. cations are of interest for use in the tests. If stainless steel
couponsaretobeused,itisrecommendedthattheybe16-gage
6.5 Miniature Barbed Fitting (see Appendix X1), for con-
andpreparedfollowingthesensitizationproceduredescribedin
1 1
nections of tubing ( ⁄16 by ⁄16 in.)(0.16 by 0.16 cm).
Test Method C692 Section 9 on Test Coupons (sensitize
6.6 Band Saw.
stainless steel coupons by heating at 1200°F (649°C) in an
argon (inert) or air (oxidizing) atmosphere for three hours).
6.7 Balance, capable of 0.0001 (60.0002) g mass determi-
Galvanized steel is not suitable for test because the elevated
nation.
temperatures recommended by the practice are above the
6.8 Wet-Grinding Belt Grinder/Sander, with used 80-grit (a
recommended use temperature of galvanized metal. However,
belt previously used to make Test Method C692 stainless steel
with suitable adjustments to slow the drip rate and lower the
coupons is acceptable) or new 120-grit wet belt.
temperature of the hot plate, there are possibilities for the
6.9 Drying Oven. development of test practices.
C1617 − 19
7.2.2 Carbon Steel Coupons ; style: 0.032 Steel, Type R, 8.5 PositionanO-ringapproximately0.5in.(91.5cm)from
Dull Matte Finish. Specs: ASTM D609-Type 1, Temper = ⁄4 asmoothflat-sandedendofthePVCpipe.Puta0.125-in.(0.32
hard,Carbon=0.13;size=0.032by2by3.5in.(0.8x51x89 cm) bead of silicone sealant completely around the space
mm) formed by the pipe and O-ring. Position the pipe in the center
7.2.3 It is likely that different results will be found when of the coupon with the hole oriented to the corner for easy
switching between various metal grades. The use of reference access. While tightly holding the pipe down, push the O-ring
solutionsofcorrosiveionsprovidesabenchmarkagainstwhich into contact with the coupon, squeezing out some silicone
the leachable ions contained in the insulation are evaluated. sealant to form a continuous, watertight seal. Avoid silicone
The reference solutions are run during every test sequence, sealant on the inside of the pipe and metal.Allow the silicone
after having previously established the range of results for the to cure completely (overnight) before testing.
individual laboratory and the type, grade, and lot of metal.
8.6 Cut1-in.(2.54cm)piecesoftheplasticstraw.Insertthe
7.3 Chemically Pure Salts and Reagent Grade Acids shall straw into the hole in the PVC pipe so that the drip falls in the
beusedforpreparationofcorrosionsolutionsusedinreference
approximatecenterofthecoupon.Thebarbedfittingisusedto
tests for plate calibration and comparison with extraction attach the straw to the peristaltic pump tube. Fig. 1 shows a
solutions.
completed test coupon with the components labeled. Figs. 2
and 3 show a hot plate with the coupons installed. Verify the
7.4 Chloride Reference Solutions are prepared from a 1000
proper setup of test coupons and solutions. It is permitted to
ppm (mg/L) chloride solution using 1.64 g of sodium chloride
mark the coupon and outside of the PVC cells with a position
tooneliterofde-ionizedwater.Foraliterofa1-mg/Lchloride
number and corresponding pump channel number.
solution, mix 1 mLof 1000 ppm chloride solution to one liter.
Quantityandconcentrationofthereferencesolutionsaremade
9. Solution Preparation
as needed for the desired test.
9.1 Procedure A:
8. Metal Coupon and Test Cell Preparation
9.1.1 Many industrial insulation materials are required to
8.1 Carbon steel coupons referenced in 7.2.2 are used as
meet the requirements of Specification C795 using Test Meth-
received from the manufacturer.
ods C692 and C871. If the material has been extracted forTest
Method C871 testing, a suitable procedure is filtration of the
NOTE 1—The previous coupon preparation technique has been moved
concentrated extraction solution through a 0.45 micron filter
to Appendix X3 (History).
followedbythedilutionoftheconcentratedextractionsolution
8.2 Permanently mark each coupon for identification. If
withde-ionizedwaterforuseinthistest.RefertoTestMethod
metal stamp impressions are used to mark the coupon, do not
C871 for the details of the extraction. Briefly described, the
allow the impression to deform the back face of the coupon.
procedure involves extracting duplicate ground-up samples of
8.3 Heat the coupons to drive off surface moisture and
20 g each in 450 g of boiling water for 30 min, adjusting the
obtain a constant weight. Cool the coupons in a moisture-free
final solution weight to 500 g, and then filtering to remove the
environment and weigh using a precision balance to 0.1 mg.
solids.
Record the weight and coupon identification.
9.1.2 Combine 375 mL from each of the two extraction
8.4 Cut the Nominal 1-in. pipe size – PVC Class 200 solutions described in 9.1.1 to provide a uniform 750-mL
Irrigation Pipe (Thin Wall) into 1.25 in. (3.175 cm) lengths. solution. Dilute 375 mL of the solution with 2625 mL of
Remove the ragged edges to make smooth flat-sanded ends. de-ionized water to total 3000 mL. One thousand millilitres of
1 1
Drilla ⁄8-in.holeinthesideofthepipe, ⁄8in.fromthetopend the resulting solution is used in a 4-day test for one metal
and then clean the pipe in de-ionized water and dry. coupon. The two extractions provide enough diluted solution
FIG. 1 Test Coupon with Components Identified
C1617 − 19
FIG. 2 Test Coupons on Hot Plate
FIG. 3 Test Cells on Hot Plate
for six coupon tests of four-day duration. The minimum 9.2.4 Stack the slices using plastic spacers (flattened plastic
recommended number of specimens per test set is three. stir-straws)betweentheslices,andsecurethestackwithrubber
Additional test sets are used to provide greater confidence in bands or monofilament fishing line.
the results. The unused 125 mL from each of the extraction
9.2.5 Place the stack or stacks in the bottom of a suitable
solutionsareavailableforTestMethodC871orotherchemical container. If the material floats, an appropriate means is
analysis.
necessary to weight the material so it remains submerged.
9.2.6 Pour in enough heated de-ionized water to cover the
9.2 Procedure B:
stack completely. If boiling water exceeds the desired extrac-
9.2.1 Thereareinsulationmaterialsthatdonotreadilywick
tion temperature, the manufacturer needs to specify the water
water, and cannot be made to wick by heat treatment. Some
temperature.
manufacturers consider it inappropriate to subject them to a
9.2.7 Agitate the contents 3 times over a 15-min period.
severe leaching of soluble ions by Procedure A because it
After 15 min, filter the water though a Whatman number 41
exposesamaximumsurfaceareatowaterforextraction,which
filter or equivalent. Rinse the container and slices with de-
would not happen under ordinary conditions of use. An
ionized water. Record the total volume of water obtained from
alternative extraction procedure is as follows:
the extraction. Filter the extraction solution through a 0.45
9.2.2 Slicethematerialcross-sectionallyonabandsawinto
micron filter.
0.25-in. (0.64 cm) wide pieces. Cut enough slices so that the
2 2 9.2.8 Adjust the final volume to 3000 mL to test three
exposed surface area totals 2 ft (1858 cm ) .A2-in.(5.08 cm)
coupons for four days.
thick block sample would require 12 slices that are 5.11-in.
(12.98cm)long.A1 ⁄2-in.(3.81cm)thickblocksamplewould
9.3 Reference Solutions:
require 16 slices that are 4.93-in. (12.52 cm) long.
9.3.1 The use of reference tests to compare the measured
9.2.3 Record the weight of the slices. corrosion resulting from the insulation solutions to that of
C1617 − 19
known corrosive solutions is mandatory for the test and allows 10.2 General Procedure:
for a degree of calibration of the practice. The number of test 10.2.1 PlaceeachcouponwiththeattachedPVCtubeonthe
coupons for each solution is three. Conduct the tests on the flat plate using sufficient high temperature grease between the
same plate at the same time as the insulation solutions. coupon and the plate to maintain good contact (no air space).
9.3.2 The reference solutions for mild steel include de- Place temperature stability insulation on top of the coupons.
ionized water and various solutions of chloride ranging from 1 10.2.2 Filltheliquidreservoirsfortheperistalticpumpwith
to 5 mg/L and ideally bracket the corrosion found for the the test and reference solutions and attach the individual feed
insulation coupons. Solutions that are more corrosive than 5 tubes to the barbs in the plastic stir-straws. Record the coupon
mg/L chloride reference solution are better tested using re- identification and solution information.
duced exposure times. The reference solutions, concentrations 10.2.3 Start the peristaltic pump previously calibrated to
and test times for aluminum and copper coupons include deliver 250 mL/day to each sample.
de-ionizedwaterandvariousionicsolutionsincludingchloride 10.2.4 Monitor the reservoir bottles daily to ascertain that
and sodium hydroxide, but these procedures have not been the delivery to each sample is 250 6 10 mL/day.
developed. 10.2.5 The time for carbon steel is equal to 96 62hto
deliver the full 1000 mLof test solution per cell. No deviation
10. Test Procedure
isallowedotherthanforapoweroutage,apluggedtubeduring
10.1 Test Plate Conditions:
the test, or startup adjustments. It is not permitted to add
10.1.1 Start the heated plate previously tested and regulated
additional solution to extend dry cells to 96 h.
to operate at 230°F (6 10°F) (100°C 66°C) with water
drippingintothetestcells.Thehotplateshallbemaintainedat
11. Cleaning Coupons
this temperature throughout the test. It is permitted to start the
11.1 The cleaning procedure is important to the accurate
test solutions dripping with the plate up to 250°F to help
determination of the weight loss due to corrosion. The goal of
prevent the cells from overfilling. The temperature shall then
any cleaning is to remove the corrosion product but minimize
be reduced to the operating range within 1 h. It is permitted to
the loss of intact metal. The use of a weighed cleaning blank
temporarily stop the peristaltic pump from dripping the solu-
coupon, that is subjected to the same cleaning procedures but
tions into the cells when cells are overfilling or an out of range
nototherwisetested,isnecessarytodetermineoftheweightof
temperature condition develops. Start the pump when the
metal loss due to the specific cleaning procedures. Additional
correct conditions are re-established.Add the stoppage time to
information about cleaning coupons after testing is written in
the end of the test if necessary. Variables influencing tempera-
Practice G1 Section 7 on Methods for CleaningAfter Testing.
ture control are: the individual heated plate, digital controller
(whenused),thermocoupleposition,topcoppersandwichplate 11.2 Remove the coupons and clean the heat transfer
medium from the back of the coupon.
(whenused),andthe
...

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: C1617 − 18a C1617 − 19
Standard Practice for
Quantitative Accelerated Laboratory Evaluation of
Extraction Solutions Containing Ions Leached from Thermal
Insulation on Aqueous Corrosion of Metals
This standard is issued under the fixed designation C1617; 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
1.1 This practice covers procedures for a quantitative accelerated laboratory evaluation of the influence of extraction solutions
containing ions leached from thermal insulation on the aqueous corrosion of metals. The primary intent of the practice is for use
with thermal insulation and associated materials that contribute to, or alternatively inhibit, the aqueous corrosion of different types
and grades of metals due to soluble ions that are leached by water from within the insulation. The quantitative evaluation criteria
are Mass Loss Corrosion Rate (MLCR) expressed in mils per year determined from the weight loss due to corrosion of exposed
metal coupons after they are cleaned.
1.2 The insulation extraction solutions prepared for use in the test can be altered by the addition of corrosive ions to the solutions
to simulate contamination from an external source. Ions expected to provide corrosion inhibition can be added to investigate their
inhibitory effect.
1.3 Prepared laboratory ionic solutions are used as reference solutions and controls, to provide a means of calibration and
comparison. See Fig. 1 and Table 1.
1.4 Other liquids can be tested for their potential corrosiveness including cooling tower water, boiler feed, and chemical stocks.
Added chemical inhibitors or protective coatings applied to the metal can also be evaluated using the general guidelines of the
practice.
1.2 This practice cannot cover all possible field conditions that contribute to aqueous corrosion. The intent is to provide an
accelerated means to obtain a non-subjective numeric value for judging the potential contribution to the corrosion of metals that
can come from ions contained in thermal insulation materials or other experimental solutions. The calculated numeric value is the
mass loss corrosion rate. This calculation is based on general corrosion spread equally over the test duration and the exposed area
of the experimental cells created for the test. Corrosion found in field situations and this accelerated test also involves pitting and
edge effects and the rate changes over time.
1.3 The insulation extraction solutions prepared for use in the test can be altered by the addition of corrosive ions to the solutions
to simulate contamination from an external source. Ions expected to provide corrosion inhibition can be added to investigate their
inhibitory effect.
1.4 Prepared laboratory ionic solutions are used as reference solutions and controls, to provide a means of calibration and
comparison.
1.5 Other liquids can be tested for their potential corrosiveness including cooling tower water, boiler feed, and chemical stocks.
Added chemical inhibitors or protective coatings applied to the metal can also be evaluated using the general guidelines of the
practice.
1.6 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.
This practice is under the jurisdiction of ASTM Committee C16 on Thermal Insulation and is the direct responsibility of Subcommittee C16.31 on Chemical and Physical
Properties.
Current edition approved Sept. 1, 2018May 1, 2019. Published October 2018June 2019. Originally approved in 2005. Last previous edition approved in 2018 as
C1617 – 18.C1617 – 18a. DOI: 10.1520/C1617-18A.10.1520/C1617-19.
The Uncertainty Test data have been moved to Appendix X4 because they are based on data obtained using laboratory fabricated old style test coupons. The precision
and bias section, using the current practice of purchased test coupons, replaces this uncertainty data. The Uncertainty Test data is preserved (for historical purposes).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1617 − 19
1.7 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.
1.8 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.
2. Referenced Documents
2.1 ASTM Standards:
A53/A53M Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless
A105/A105M Specification for Carbon Steel Forgings for Piping Applications
C168 Terminology Relating to Thermal Insulation
C518 Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus
C665 Specification for Mineral-Fiber Blanket Thermal Insulation for Light Frame Construction and Manufactured Housing
C692 Test Method for Evaluating the Influence of Thermal Insulations on External Stress Corrosion Cracking Tendency of
Austenitic Stainless Steel
C739 Specification for Cellulosic Fiber Loose-Fill Thermal Insulation
C795 Specification for Thermal Insulation for Use in Contact with Austenitic Stainless Steel
C871 Test Methods for Chemical Analysis of Thermal Insulation Materials for Leachable Chloride, Fluoride, Silicate, and
Sodium Ions
C1696 Guide for Industrial Thermal Insulation Systems
D609 Practice for Preparation of Cold-Rolled Steel Panels for Testing Paint, Varnish, Conversion Coatings, and Related Coating
Products
G1 Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens
G16 Guide for Applying Statistics to Analysis of Corrosion Data
G31 Guide for Laboratory Immersion Corrosion Testing of Metals
G46 Guide for Examination and Evaluation of Pitting Corrosion
3. Terminology
3.1 Definitions: Refer to Terminology C168 for definitions relating to insulation.
4. Summary of Practice
4.1 The practice uses controlled amounts of test solutions delivered drip wise onto a defined area of small flat coupons of
selected test metals for the purpose of producing, comparing, and measuring the corrosion that occurs on the metals due to the
exposure.
4.2 The test is conducted at elevated temperatures, greatly accelerating the corrosion in comparison with corrosion at room
temperature. The heat makes the solution evaporate quickly, allowing an air (oxygen) interface and making thousands of
wet-dry-wet cycles possible in a short time.
4.3 Quantitative measurements of corrosion are determined from the weight change (loss) due to the corrosion of the tested
coupons. Reference tests prepared with known concentrations of solutions that are conducive to the corrosion of the tested metal
are compared with water solutions containing ions extracted from insulation samples. Calculations of MLCR in mils-per-year
(MPY) made using the methods of Practice G1 are reportedrecorded as the quantitative measurement. The measurements are used
to determine compliance with the applicable ASTM material specifications on a pass/fail basis when compared to the corrosion
reference solutions that were tested at the same time as the insulation extraction solutions. No other comparisons shall be made.
5. Significance and Use
5.1 Results from this accelerated corrosion test shall not be considered as an indicator of the useful life of the metal equipment.
Many factors need consideration for applicability to specific circumstances. Refer to Guide C1696 and Practice G31 for additional
information.
5.2 Corrosion associated with insulation is an important concern for insulation manufacturers, specification writers, designers,
contractors, users and operators of the equipment. Some material specifications contain test methods (or reference test methods
contained in other material specifications), for use in evaluating the insulation with regard to the corrosion of steel, copper, and
aluminum. In some cases these tests are not applicable or effective and have not been evaluated for precision and bias.
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.
C1617 − 19
5.3 A properly selected, installed, and maintained insulation system will reduce the corrosion that often occurs on an
un-insulated structure. However, when the protective weather-resistant covering of an insulation system fails, the conditions for
the aqueous environment necessary for corrosion under insulation (CUI) often develop. It is possible the insulation contains,
collects, or concentrates corrosive agents, or a combination thereof, often found in industrial and coastal environments. If water
is not present, these electrolytes cannot migrate to the metal surface. The electrochemical reaction resulting in the aqueous
corrosion of metal surfaces cannot take place in the absence of water and electrolytes. Additional environmental factors
contributing to increased corrosion rates are oxygen, and elevated-temperature (near boiling point).
5.4 Chlorides and other corrosive ions are common to many environments. The primary corrosion preventative is to protect
insulation and metal from contamination and moisture. Insulation covers, jackets, and metal coating of various kinds are often used
to prevent water infiltration and contact with the metal.
5.5 This procedure can be used to evaluate all types of thermal insulation and fireproofing materials (industrial, commercial,
residential, cryogenic, fire-resistive, insulating cement) manufactured using inorganic or organic materials, faced or unfaced, for
which a filtered extraction solution can be obtained.
5.6 This procedure can be used with all metal types for which a coupon can be prepared such as mild steel, stainless steel,
copper, or aluminum. Other metals (copper, aluminum) will need different times, reference solutions and cleaning practices. It shall
not be interpreted that the steel procedures work for everything. When procedures are developed for other metals they will be
balloted for inclusion in the document.
5.7 This procedure can also be applicable to insulation accessories including jacketing, covers, adhesives, cements, and binders
associated with insulation and insulation products.
5.8 Heat treatment of the insulation (as recommended by the manufacturer up to the maximum potential exposure temperature)
can be used to simulate possible conditions of use.
5.9 Adhesives can be tested by first drying followed by water extraction or by applying a known quantity of the test adhesive
to a test piece of insulation and then extracting.
5.10 Insulating cements can be tested by casting a slab, drying, and extracting or by using the uncured insulating cement powder
for extraction.
5.11 Reference tests prepared with various concentrations of solutions that are conducive to the corrosion of the tested metal
serve as comparative criteria. Solutions containing chloride, sodium hydroxide, various acids (sulfuric, hydrochloric, nitric, and
citric acid), as well as “blank” tests using only de-ionized water and tap water are used.
5.12 Research can be done on insulation that has been specially formulated to inhibit corrosion in the presence of corrosive ions
through modifications in basic composition or incorporation of certain chemical additives. Corrosive ions can also be added to the
insulation extraction solutions to determine the effectiveness of any inhibitors present.
5.13 Protective surface treatments and coatings of different types and thickness can be applied to the metal coupons and
compared using various corrosive liquids.
5.14 Several sets of tests are recommended because of the number of factors that affect corrosion. An average of the tests and
the standard deviation between the test results are used on the data. Much of the corrosion literature recommends a minimum of
three specimens for every test. Consult Guide G16 for additional statistical methods to apply to the corrosion data.
5.14 Results from this accelerated corrosion test shall not be considered as an indicator of the useful life of the metal equipment.
Many factors need consideration for applicability to specific circumstances. Refer to Practice G31 for additional information.
6. Apparatus
6.1 The test apparatus must be housed in a reasonably clean and non-dusty environment to avoid any effects of contaminants.
6.2 Heated Temperature Controlled Flat Hot Plate (see Appendix X1)—A 1-ft (30.5-cm) square or circular plate that has
uniform temperature across the surface provides the heated environment. See Appendix X1 for construct design and sources of
assembled systems. Larger plates for testing more coupons are not excluded.
6.3 Peristaltic Pump (see Appendix X1)—A multi-channel peristaltic pump with individual cassettes and silicone tubes is
recommended to supply 250 (625)(610) mL/day to each specimen. Pump rates must be well controlled.
6.4 Silicone Rubber Tubing (see Appendix X1), to deliver fluid to the test coupons.
1 1
6.5 Miniature Barbed Fitting (see Appendix X1), for connections of tubing ( ⁄16 by ⁄16 in.)(0.16 by 0.16 cm).
6.6 Band Saw.
6.7 Balance, capable of 0.0001 (60.0002) g mass determination.
6.8 Wet-Grinding Belt Grinder/Sander, with used 80-grit (a belt previously used to make Test Method C692 stainless steel
coupons is acceptable) or new 120-grit wet belt.
C1617 − 19
6.9 Drying Oven.
6.10 Bottles, plastic 1 L or equivalent, to individually supply each test specimen with test liquid.
5 3
6.11 Nominal 1-in. Thin-wall PVC Pipe, Pipe Size – PVC Class 200 Irrigation Pipe (Thin Wall), 1 ⁄16-in. (3.33 cm) OD; 1 ⁄16-in.
(3.02 cm) ID by 1.25-in. (3.18 cm)lengths.cm) lengths.
6.12 High Temperature Grease or oil,Oil, for use as heat transfer medium.
1 1 1
6.13 Rubber O-Ring, 1 ⁄4-in. (3.18 cm) ID, 1 ⁄2-in. (3.81 cm) OD, ⁄8-in. (0.32 cm)thick.
6.14 Silicone Sealant, 100% 100 % Silicone sealant.
6.15 Plastic Straw, ⁄8-in. (0.32 cm) drink stirring straw (“swizzle stick”) .
6.16 Cleaning Apparatus and Solutions, for the coupons, stainless steel metal scourer pad, 3-M sanding carbon steel coupons,
Hydrochloric acid diluted 1 part to 3 parts water, razor widget, sodium bicarbonate (baking soda) solution for neutralizer, xylene,
water paper or cloth towels, Wet Laid, Nonwoven Fiberglass Facing ⁄16pad (medium and fine) or equivalent sand paper, acetone,
xylene, water, paper towels. in. thick – works well as a sacrificial scrubbing pad with the diluted HCL to clean and polish the
coupons.
6.17 Hand-Held Magnifier, or 10 to 30× binocular microscope, or both.
6.18 Filter, 0.45 micron filter paper.
7. Reagents and Materials
7.1 Distilled or De-Ionized Water, containing less than 0.1 ppm chloride ions. Some de-ionized and reverse osmosis water have
been found not to be pure enough. This water is used to make the test solutions and reference solutions. The “zero chloride” water
test reference solution results are expected to be only slightly higher than the cleaning blank result.
7.2 Metal Test Coupons, meeting the composition requirements of applicable ASTM Specification for Mild Steel, Stainless
Steel, Copper, or Aluminum. Mill certificates of chemical composition and mechanical properties are required.
7.2.1 Some researchers will want to maintain traceability to the metals used in other C16 corrosion procedures. Specification
C739 uses cold rolled, low carbon (<0.30 %) commercial quality shim steel. Specification C665 uses cold rolled, low carbon,
quarter hard, temper No. 3, strip steel. It is possible other metal grades meeting Specification A53/A53M, Specification
A105/A105M, and other common ferrous steel specifications are of interest for use in the tests. If stainless steel coupons are to
be used, it is recommended that they be 16-gage and prepared following the sensitization procedure described in Test Method C692
Section 9 on Test Coupons (sensitize stainless steel coupons by heating at 1200°F (649°C) in an argon (inert) or air (oxidizing)
atmosphere for three hours). Galvanized steel is not suitable for test because the elevated temperatures recommended by the
practice are above the recommended use temperature of galvanized metal. However, with suitable adjustments to slow the drip rate
and lower the temperature of the hot plate, there are possibilities for the development of test practices.
7.2.2 Carbon Steel Coupons ; style: 0.032 Steel, Type R, Dull Matte Finish. Specs: ASTM D609-Type 1, Temper = ⁄4 hard,
Carbon = 0.13; size = 0.032 by 2 by 3.5in. (0.8 x 51 x 89 mm)
7.2.3 It is likely that different results will be found when switching between various metal grades. The use of reference solutions
of corrosive ions provides a benchmark against which the leachable ions contained in the insulation are evaluated. The reference
solutions are run during every test sequence, after having previously established the range of results for the individual laboratory
and the type, grade, and lot of metal.
7.3 Chemically Pure Salts and Reagent Grade Acids shall be used for preparation of corrosion solutions used in reference tests
for plate calibration and comparison with extraction solutions.
7.4 Chloride Reference Solutions are prepared from a 1000 ppm (mg/L) chloride solution using 1.64 g of sodium chloride to
one liter of de-ionized water. For a liter of a 1-mg/L chloride solution, mix 1 mL of 1000 ppm chloride solution to one liter.
Quantity and concentration of the reference solutions are made as needed for the desired test.
8. Metal Coupon and Test Cell Preparation
8.1 Carbon steel coupons referenced in 7.2.2 are used as received from the manufacturer.
NOTE 1—The previous coupon preparation technique has been moved to Appendix X3 (History).
8.2 Permanently mark each coupon for identification. If metal stamp impressions are used to mark the coupon, do not allow the
impression to deform the back face of the coupon.
8.3 Heat the coupons to drive off surface moisture and obtain a constant weight. Cool the coupons in a moisture-free
environment and weigh using a precision balance to 0.1 mg. Record the weight and coupon identification.
8.4 Cut the polyvinylchloride (PVC) pipe into 1.25in.(3.175 Nominal 1-in. pipe size – PVC Class 200 Irrigation Pipe (Thin
Wall) into 1.25 in. (3.175 cm) lengths. Remove the ragged edges to make smooth flat-sanded ends. Drill a ⁄8-in. hole in the side
of the pipe, ⁄8 in. from the top end and then clean the pipe in de-ionized water and dry.
C1617 − 19
8.5 Position an O-ring approximately 0.5 in. (91.5 cm) from a smooth flat-sanded end of the PVC pipe. Put a 0.125-in.(0.32
cm) bead of silicone sealant completely around the space formed by the pipe and O-ring. Position the pipe in the center of the
coupon with the hole oriented to the corner for easy access. While tightly holding the pipe down, push the O-ring into contact with
the coupon, squeezing out some silicone sealant to form a continuous, watertight seal. Avoid silicone sealant on the inside of the
pipe and metal. Allow the silicone to cure completely (overnight) before testing.
8.6 Cut 1-in. (2.54 cm) pieces of the plastic straw with one end at a 45° angle. straw. Insert the straw into the hole in the PVC
pipe so that the angle is down and the drip falls in the approximate center of the coupon. The barbed fitting is used to attach the
straw to the peristaltic pump tube. Fig. 21 shows a completed test coupon with the components labeled. Figs. 32 and 43 show a
hot plate with the coupons installed. Verify the proper setup of test coupons and solutions. It is permitted to mark the coupon and
outside of the PVC cells with a position number and corresponding pump channel number.
9. Solution Preparation
9.1 Procedure A:
9.1.1 Many industrial insulation materials are required to meet the requirements of Specification C795 using Test Methods C692
and C871. If the material has been extracted for Test Method C871 testing, a suitable procedure is filtration of the concentrated
extraction solution through a 0.45 micron filter followed by the dilution of the concentrated extraction solution with de-ionized
water for use in this test. Refer to Test Method C871 for the details of the extraction. Briefly described, the procedure involves
extracting duplicate ground-up samples of 20 g each in 450 g of boiling water for 30 min, adjusting the final solution weight to
500 g, and then filtering to remove the solids.
9.1.2 Combine 375 mL from each of the two extraction solutions described in 9.1.1 to provide a uniform 750-mL solution.
Dilute 375 mL of the solution with 2625 mL of de-ionized water to total 3000 mL. One thousand millilitres of the resulting solution
is used in a 4-day test for one metal coupon. The two extractions provide enough diluted solution for six coupon tests of four-day
duration. The minimum recommended number of specimens per test set is three. Additional test sets are used to provide greater
confidence in the results. The unused 125 mL from each of the extraction solutions are available for Test Method C871 or other
chemical analysis.
9.2 Procedure B:
9.2.1 There are insulation materials that do not readily wick water, and cannot be made to wick by heat treatment. Some
manufacturers consider it inappropriate to subject them to a severe leaching of soluble ions by Procedure A because it exposes a
maximum surface area to water for extraction, which would not happen under ordinary conditions of use. An alternative extraction
procedure is as follows:
9.2.2 Slice the material cross-sectionally on a band saw into 0.25-in. (0.64 cm) wide pieces. Cut enough slices so that the
2 2
exposed surface area totals 2 ft (1858 cm ) . A 2-in.(5.08 cm) thick block sample would require 12 slices that are 5.11-in. (12.98
cm) long. A 1 ⁄2-in. (3.81 cm) thick block sample would require 16 slices that are 4.93-in. (12.52 cm) long.
9.2.3 Record the weight of the slices.
9.2.4 Stack the slices using plastic spacers (flattened plastic stir-straws) between the slices, and secure the stack with rubber
bands or monofilament fishing line.
9.2.5 Place the stack or stacks in the bottom of a suitable container. If the material floats, an appropriate means is necessary to
weight the material so it remains submerged.
9.2.6 Pour in enough heated de-ionized water to cover the stack completely. If boiling water exceeds the desired extraction
temperature, the manufacturer needs to specify the water temperature.
FIG. 1 Test Coupon with Components Identified
C1617 − 19
FIG. 2 Test Coupons on Hot Plate
FIG. 3 Test Cells on Hot Plate
9.2.7 Agitate the contents 3 times over a 15-min period. After 15 min, filter the water though a Whatman number 41 filter or
equivalent. Rinse the container and slices with de-ionized water. Record the total volume of water obtained from the extraction.
Filter the extraction solution through a 0.45 micron filter.
9.2.8 Adjust the final volume to 3000 mL to test three coupons for four days.
9.3 Reference Solutions:
9.3.1 The use of reference tests to compare the measured corrosion resulting from the insulation solutions to that of known
corrosive solutions is mandatory for the test and allows for a degree of calibration of the practice. Ideally the The number of test
coupons for each solution is three. Conduct the tests on the same plate at the same time as the insulation solutions.
9.3.2 The reference solutions for mild steel and copper coupons include de-ionized water and various solutions of chloride
ranging from 1 to 5 mg/L and ideally bracket the corrosion found for the insulation coupons. The reference solutions for aluminum
coupons include de-ionized water and various solutions of sodium hydroxide. Solutions that are more concentratedcorrosive than
5 mg/L produce high corrosion and chloride reference solution are better tested using reduced exposure times. The reference
solutions, concentrations and test times for aluminum and copper coupons include de-ionized water and various ionic solutions
including chloride and sodium hydroxide, but these procedures have not been developed.
10. Test Procedure
10.1 Test Plate Conditions:
10.1.1 Start the heated plate previously tested and regulated to operate at 230°F (6 10°F) (100°C 66°C) with water dripping
into the test cells. The hot plate shall be maintained at this temperature throughout the test. It is important to establish this control
prior to beginning tests for data collection. permitted to start the test solutions dripping with the plate up to 250°F to help prevent
the cells from overfilling. The temperature shall then be reduced to the operating range within 1 h. It is permitted to temporarily
stop the peristaltic pump from dripping the solutions into the cells when cells are overfilling or an out of range temperature
condition develops. Start the pump when the correct conditions are re-established. Add the stoppage time to the end of the test if
C1617 − 19
necessary. Variables influencing temperature control are: the individual heated plate, digital controller (when used), thermocouple
position, top copper sandwich plate (when used), and the insulation covering the thermocouple and coupons (when used). When
any changes are made it is necessary to re-establish the temperature control of the test set-up. Temperature stability is improved
by using thermal insulation on top of the coupons and between the cell tubes.
NOTE 2—Glass fiber felt, 0.5-in (1.5 cm) thick with an aluminum foil barrier to prevent heat transfer fluid uptake, and also EPDM-based elastomeric
foam insulation have been successfully used for temperature control.
10.1.2 It is useful to test the evaporation rate of each coupon, especially on newly constructed plates, to verify that the coupons
are being heated evenly. Start the peristaltic pump with the feed tubes in de-ionized water and allow the temperature controller to
stabilize. Turn off the peristaltic pump and quickly fill all the test coupon cells with 1 mL of de-ionized water using an automatic
pipette. Determine the time it takes for the first cell to evaporate the water (expect 2 to 3 min) and verify that the other cells dry
within 45 s of the first. When necessary, reposition or otherwise adjust the coupons.
10.1.3 New plates are evaluated by performing a number of tests using only reference solutions to determine the range of the
results for each solution. A Frequency Histogram similar to Fig. 1the one shown in Appendix X4 is developed for the individual
lab, test equipment, and metal used in the test. Guide G16 is helpful in analyzing the data.
10.1.4 A small fan used to circulate the air above the test apparatus is recommended to help the evaporation process by moving
the air saturated with
...