1、 Standard Practice Coatings and Linings over Concrete for Chemical Immersion and Containment Service This NACE International standard represents a consensus of those individual members who have reviewed this document, its scope, and provisions. Its acceptance does not in any respect preclude anyone,
2、 whether he or she has adopted the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not in conformance with this standard. Nothing contained in this NACE International standard is to be construed as granting any right, by implication or otherwis
3、e, to manufacture, sell, or use in connection with any method, apparatus, or product covered by Letters Patent, or as indemnifying or protecting anyone against liability for infringement of Letters Patent. This standard represents minimum requirements and should in no way be interpreted as a restric
4、tion on the use of better procedures or materials. Neither is this standard intended to apply in all cases relating to the subject. Unpredictable circumstances may negate the usefulness of this standard in specific instances. NACE International assumes no responsibility for the interpretation or use
5、 of this standard by other parties and accepts responsibility for only those official NACE International interpretations issued by NACE International in accordance with its governing procedures and policies which preclude the issuance of interpretations by individual volunteers. Users of this NACE I
6、nternational standard are responsible for reviewing appropriate health, safety, environmental, and regulatory documents and for determining their applicability in relation to this standard prior to its use. This NACE International standard may not necessarily address all potential health and safety
7、problems or environmental hazards associated with the use of materials, equipment, and/or operations detailed or referred to within this standard. Users of this NACE International standard are also responsible for establishing appropriate health, safety, and environmental protection practices, in co
8、nsultation with appropriate regulatory authorities if necessary, to achieve compliance with any existing applicable regulatory requirements prior to the use of this standard. CAUTIONARY NOTICE: NACE International standards are subject to periodic review, and may be revised or withdrawn at any time i
9、n accordance with NACE technical committee procedures. NACE International requires that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of initial publication. The user is cautioned to obtain the latest edition. Purchasers of NACE International s
10、tandards may receive current information on all standards and other NACE International publications by contacting the NACE International FirstService Department, 1440 South Creek Dr., Houston, Texas 77084-4906 (telephone +1281228-6200). Reaffirmed 2007-08-14 Revised 2001-10-03 Approved December 1992
11、 NACE International 1440 South Creek Drive Houston, Texas 77084-4906 +1 281/228-6200 ISBN 1-57590-136-6 2007, NACE International NACE SP0892-2007 (formerly RP0892-2001) Item No. 21060 SP0892-2007 NACE International i _ Foreword Concrete is used in power facilities, chemical processing plants, pulp a
12、nd paper mills, petrochemical plants, water and wastewater treatment plants, food and beverage plants, and mining operations. Concrete frequently provides structural support for steel in industrial applications; it is also used for catch basins, troughs, machinery mounts, spill containment, and imme
13、rsion service. Concrete, unlike steel, is not a predictable, uniform substrate. Concrete is very porous and in many industrial exposures is likely to absorb chemical contamination and water, which can cause spalling and eventual loss of structural integrity. When providing corrosion protection for c
14、oncrete substrates, consideration must be given to the use of liquid, organic, chemical-resistant coatings and their proper application and inspection. This standard practice sets forth guidelines for the application of quality protective coating systems to properly prepared concrete surfaces. Infor
15、mation contained herein is intended as a guide for personnel who prepare specifications, standards, and procedures for the coating or lining of concrete surfaces. The information provided in this standard is based on the best current knowledge and experience of committee members and not necessarily
16、on reproducible scientific evidence. This standard was originally prepared in 1992 by NACE Task Group (TG) T-6A-59 on Coatings/Linings over Concrete for Immersion Service, which was a component of Unit Committee T-6A on Coating and Lining Materials for Immersion Service. It was technically revised i
17、n 2001 by TG 141. This TG is administered by Specific Technology Group (STG) 03 on Protective Coatings and LiningsImmersion Service. It was reaffirmed in 2007 by STG 03. This standard is published by NACE International under the auspices of STG 03. In NACE standards, the terms shall, must, should, a
18、nd may are used in accordance with the definitions of these terms in the NACE Publications Style Manual, 4th ed., Paragraph 7.4.1.9. Shall and must are used to state mandatory requirements. The term should is used to state something good and is recommended but is not mandatory. The term may is used
19、to state something considered optional. _ SP0892-2007 ii NACE International _ NACE International Standard Practice Coatings and Linings over Concrete for Chemical Immersion and Containment Service Contents 1. General. 1 2. Definitions 1 3. Concrete Design and Surface Preparation Requirements. 2 4. C
20、oating System Design Requirements 3 5. Coating Applications. 4 6. Inspection . 4 7. Safety . 6 References 5 Bibliography 7 Appendix A: Properties of Concrete (Nonmandatory) 7 Appendix B: Surface Preparation (Nonmandatory) 10 Appendix C: Selection of Coatings (Nonmandatory) 12 Appendix D: Coating Sys
21、tem Properties (Nonmandatory) . 13 _ SP0892-2007 NACE International 1 _ Section 1: General 1.1 Concrete is coated for one or more of the following reasons: To obtain a surface that is resistant to the environment To provide a surface that is resistant to immersion, splashes, spills, and vapors from
22、corrosive solutions stored in tanks or vessels To provide a surface that prevents product contamination (i.e., from constituents present in concrete) To provide a surface for floors that is resistant to chemical spills, mechanical damage, and wear from foot or vehicular traffic To protect structural
23、 rebar from corrosion To prevent degradation of the concrete To obtain a surface that is easier to clean than concrete To obtain a surface of improved appearance (in an aesthetic type of application) 1.2 This standard sets forth guidelines for the selection and installation of liquid organic coating
24、s to be used over properly prepared concrete surfaces exposed to immersion conditions or chemical splash and spillage. The term lining is commonly used to describe a coating used to protect a structural substrate from the contained chemical. For simplicity, in this standard, the term coating (or coa
25、ting system) is used when referring to any protective system, whether used as a lining, floor surfacer, or a coating. 1.3 This standard also addresses the following subjects: Proper cleaning and surface preparation of concrete, which is vital to the life and performance of the selected organic coati
26、ng Service conditions (physical and chemical severity) to which the coating may be exposed Selection of coatings through the use of laboratory and field tests Inspection of the coating system during and after application to the concrete surface 1.4 The composition and installation of new concrete mu
27、st be properly specified for the application of a coating system. It is the responsibility of the owner/specifier to specify the concrete composition, admixtures, finishing procedures, and curing and form release agents that render the concrete suitable for coating. The physical properties of the co
28、ncrete must also be specified according to design parameters, and the chemical, physical (abrasion), and environmental exposure must be defined in order for the coating system to be properly selected. 1.5 This standard calls attention to basic safety precautions and procedures regarding the handling
29、 and use of coating materials and solvents. NACE Publication TPC #21contains more detailed information. Material Safety Data Sheets (MSDS) supplied by the coating manufacturer provide specific safety information. 1.6 This standard should not be used for containment in nuclear power plants. _ Section
30、 2: Definitions Adhesion: State in which two surfaces are held together by interfacial forces that may consist of valence forces, interlocking action, or both. Aspect ratio: On a two-dimensional shape, the ratio of its longer dimension to its shorter dimension. Bugholes: Small regular or irregular c
31、avities, usually not exceeding 15 mm (0.60 in.) in diameter, resulting from entrapment of air bubbles in the surface of formed concrete during placement and compaction. Concrete: A composite material that consists essentially of a binding medium within which are embedded particles or fragments of ag
32、gregate; in portland cement concrete, the binder is a mixture of portland cement and water. Contaminant, Contamination: Any extraneous material on the concrete surface that will affect the adhesion of the applied coating to the concrete. Contraction Joint: Formed, sawed, or tooled groove in a concre
33、te structure to create a weakened plane and regulate the location of cracking resulting from the dimensional change of different parts of the structure. Crack: See Dynamic Crack and Static Crack. Cure, Curing (of concrete): The maintenance of a satisfactory moisture content and temperature in concre
34、te during its early stages so that desired properties may develop. SP0892-2007 2 NACE International Curing (of coating): Chemical process of developing the intended properties of a coating or other material (e.g., resin) over a period of time. Curling (of concrete): The distortion of an essentially
35、linear or planar member into a curved shape such as the warping of a slab due to creep or differences in temperature or moisture content in the zones adjacent to its opposite faces. Dynamic Crack: A crack in the concrete surface whose width changes as the concrete moves. Efflorescence: A white cryst
36、alline or powdery deposit on the surface of concrete. Efflorescence results from leaching of lime or calcium hydroxide out of a permeable concrete mass over time by water, followed by reaction with carbon dioxide and acidic pollutants. Fines: Clay or silt particles in soil often found in a concrete
37、mix. Holiday: A discontinuity in a protective coating that exposes unprotected surface to the environment. Honeycomb: Concrete that, due to lack of the proper amount of fines or vibration, contains abundant interconnected large voids or cavities; concrete that contains honeycombs was improperly cons
38、olidated. Isolation Joint: A separation between adjoining parts of a concrete structure. Joint: See Contraction Joint and Isolation Joint. Laitance: A thin, weak, brittle layer of cement and aggregate fines on a concrete surface. The amount of laitance is influenced by the degree of working or the a
39、mount of water in the concrete. Pot Life: The elapsed time within which a coating can be effectively applied after all components of the coating have been thoroughly mixed. Scaling: Flaking or peeling away of the near-surface portion of hydraulic cement, concrete, or mortar. Spalling: Cracking, brea
40、king, chipping, or fraying of a concrete slabs surface; usually within a confined area less than 0.5 m2(5 ft2). Static Crack: A crack in the concrete surface whose width does not change. Surface Preparation: The method or combination of methods used to clean a concrete surface, remove loose and weak
41、 materials and contaminants from the surface, repair the surface, and roughen the surface to promote adhesion of a coating. _ Section 3: Concrete Design and Surface Preparation Requirements 3.1 New concrete structures for use in primary containment, secondary containment, or monolithic flooring shal
42、l be designed following the guidelines in ACI(1)350-062ACI 350.2 R,3or ACI 302.1 R,4respectively. Appendix A (nonmandatory) presents general information about the properties of concrete. The design shall include guidelines for the following details. (a) Mix design, including minimum cement content,
43、maximum water content, and minimum air content (b) Placement and finishing procedures (c) Curing procedures, including temperature limits, method of cure, and length of curing (d) Joints, including design and location (e) Vapor barrier or external waterproofing 3.2 Existing concrete structures to be
44、 lined should be tested for soundness. Damage and defects should be repaired to the requirements of the coating system to be applied using materials, such as polymeric or cementitious grouts, that are compatible with the subsequent coating materials. 3.2.1 Physical and chemical damage should be repa
45、ired using procedures described in ICRI(2)Guide No. 03730.53.2.2 Other defects such as honeycombs, scaling, and spalling shall be patched prior to surface preparation. 3.2.3 Surface voids, tieholes, bugholes, pinholes, and excess porosities should be filled prior to the application of a coating syst
46、em. 3.2.4 Protrusions such as form lines, fins, sharp edges, and spatter should be removed during surface preparation. _ (1)American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094.(2)International Concrete Repair Institute (ICRI), 1323 Shepherd Dr., Suite D, Sterling, VA 20
47、164. SP0892-2007 NACE International 3 3.3 Surface preparation shall be performed according to NACE No. 6/SSPC(3)-SP 136using the test methods and acceptance criteria for severe service presented in Paragraph 3.3.1 through Paragraph 3.3.7 of this standard. Additional information on surface preparatio
48、n is presented in Appendixes A and B (nonmandatory). 3.3.1 Laitance and Contaminants: All laitance and loose or weak concrete shall be removed from the surface. All concrete surfaces suspected of being exposed to contaminants shall be tested by methods described in NACE No. 6/SSPC-SP 13. Removal of laitance and contaminants shall be verified by a patch test