NACE WJ-1-2012 Waterjet Cleaning of Metals-Clean to Bare Substrate (WJ-1) (Item No 21154).pdf

1、 Joint Surface Preparation Standard Waterjet Cleaning of Metals Clean to Bare Substrate (WJ-1) This NACE International/SSPC: The Society for Protective Coatings joint surface preparation standard represents a consensus of those individual members who have reviewed this document, its scope, and provi

2、sions. Its acceptance does not in any respect preclude anyone, 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 practice. Nothing contained in this NACE/SSPC standard is to

3、be construed as granting any right, by implication or otherwise, 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

4、 requirements and should in no way be interpreted as a restriction on the use of better procedures or materials not discussed herein. 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 in

5、stances. NACE and SSPC assume no responsibility for the interpretation or use of this standard by other parties, and accept responsibility for only those official NACE or SSPC interpretations issued by NACE or SSPC in accordance with their governing procedures and policies, which preclude the issuan

6、ce of interpretations by individual volunteers. Users of this NACE/SSPC standard are responsible for reviewing appropriate health, safety, and regulatory documents and for determining their applicability in relation to this standard prior to its use. This NACE/SSPC standard may not necessarily addre

7、ss all potential health and safety 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/SSPC standard also are responsible for establishing appropriate health, safety, and environmental p

8、rotection practices, in consultation 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/SSPC joint surface preparation standards are subject to periodic review, an

9、d may be revised or withdrawn at any time in accordance with NACE/SSPC technical committee procedures. NACE and SSPC require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of initial publication and subsequently from the date of each reaffi

10、rmation or revision. The user is cautioned to obtain the latest edition. Purchasers of NACE/SSPC standards may receive current information on all standards and other NACE/SSPC joint publications by contacting the organizations at the addresses below: ISBN 1-57590-248-6 2012, NACE and SSPC NACE Inter

11、national 1440 South Creek Drive Houston, TX 77084-4906 +1 281-228-6200 The Society for Protective Coatings 40 24th Street, 6th Floor Pittsburgh, PA 15222-4656 +1 412-281-2331Approved: 2012-03-10 Printed by NACE InternationalItem 21158 NACE WJ-1/SSPC-SP WJ-1 NACE International i _ Foreword This NACE/

12、SSPC joint standard defines the Clean to Bare Substrate (WJ-1) degree of surface cleanliness of coated or uncoated metallic substrates achieved by the use of waterjet cleaning prior to the application of a protective coating or lining. Waterjet cleaning is the use of pressurized surface preparation

13、water for removing coatings and other materials, including hazardous materials, from a substrate to achieve a defined degree of surface cleanliness. Waterjet cleaning includes various methods such as low-pressure water cleaning (LP WC), high-pressure water cleaning (HP WC), high-pressure waterjettin

14、g (HP WJ), and ultrahigh-pressure waterjetting (UHP WJ). The four degrees of surface cleanliness achieved by waterjet cleaning, which are addressed in separate standards, are as follows: Degree of Surface Cleanliness Designation Clean to Bare Substrate WJ-1 Very Thorough Cleaning WJ-2 Thorough Clean

15、ing WJ-3 Light Cleaning WJ-4 Clean to Bare Substrate (WJ-1) provides a greater degree of surface cleanliness than Very Thorough Cleaning (WJ-2). Waterjet cleaning to achieve the Clean to Bare Substrate (WJ-1) degree of surface cleanliness is used when the objective is to remove every trace of rust a

16、nd other corrosion products, coating, and mill scale. Discoloration of the surface may be present. Waterjet cleaning does not provide the primary anchor pattern on the metallic substrate known as “surface profile.” The coatings industry uses waterjet cleaning primarily for recoating or relining proj

17、ects in which there is an adequate pre-existing surface profile. The degrees of surface cleanliness cited above to be achieved by waterjet cleaning methods are not intended to require that a surface profile be present or defined prior to coating application. Waterjet cleaning reduces and may complet

18、ely remove water-soluble surface contaminants, notably those contaminants found at the bottom of pits on the surface of corroded metallic substrates. Waterjet cleaning also helps remove oil, grease, rust and other corrosion products, and other foreign matter (for example, shotcrete spatter) from the

19、 surface, and is used when it is a more feasible method of surface preparation than, for example, abrasive blast cleaning, power or hand tool cleaning, or chemical stripping. Waterjet cleaning may be used when the application of high-performance coatings requires extensive surface preparation, surfa

20、ce decontamination, or both. This standard is intended for use by coating or lining specifiers, applicators, inspectors, or others who have responsibility to define a standard degree of surface cleanliness to be achieved by waterjet cleaning methods. NACE WJ-1/SSPC-SP WJ-1 ii NACE International This

21、 standard was prepared by NACE/SSPC Joint Task Group (TG) 275, “Surface Preparation of Metals to WJ-1 (Clean to Bare Substrate) by High-Pressure Waterjetting.” TG 275 is administered by Specific Technology Group (STG) 04, “Coatings and Linings, ProtectiveSurface Preparation,” and is sponsored by STG

22、 02, “Coatings and Linings, ProtectiveAtmospheric,” and STG 03, “Coatings and Linings, ProtectiveImmersion and Buried Service.” This standard is issued by NACE under the auspices of STG 04, and by SSPC Group Committee C.2 on Surface Preparation. This standard is one of a set of four standards on deg

23、rees of surface cleanliness to be achieved by waterjet cleaning that are intended to replace NACE No. 5/SSPC-SP 12,1 which includes all four degrees of surface cleanliness. In NACE/SSPC standards, the terms shall, must, should, and may are used in accordance with Paragraph 2.2.1.8 of the Agreement b

24、etween NACE International and SSPC: The Society for Protective Coatings. The terms shall and must are used to state mandatory requirements. The term should is used to state something considered good and is recommended, but is not mandatory. The term may is used to state something considered optional

25、. _ NACE WJ-1/SSPC-SP WJ-1 NACE International iii _ NACE/SSPC Joint Surface Preparation Standard Waterjet Cleaning of Metals Clean to Bare Substrate (WJ-1) Contents 1. General 1 2. Definitions .1 3. Additional Technical Considerations .2 4. Associated Documents .2 5. Procedures Before Waterjet Clean

26、ing3 6. Waterjet Cleaning Methods 3 7. Procedures Following Waterjet Cleaning and Immediate Prior to Coating.4 References 4 Appendix A: Explanatory Notes (Nonmandatory) 5 Appendix B: Methods of Assessing the Degree of Flash Rust (Nonmandatory) 8 Appendix C: Waterjet Cleaning Equipment and Operating

27、Parameters (Nonmandatory) 9 TABLE B1: Assessment of Degree of Flash RushTape Pull Test 9 _ NACE WJ-1/SSPC-SP WJ-1 NACE International 1 _ Section 1: General 1.1 This standard defines the Clean to Bare Substrate (WJ-1) degree of surface cleanliness of uncoated or coated metallic substrates by use of w

28、aterjet cleaning. The defined degree of cleanliness shall be achieved prior to the application of a specified protective coating or lining system. These requirements include the end condition of the surface and materials and procedures necessary to achieve and verify the end condition, as determined

29、 by visual inspection. This standard also may be used in situations in which the degree of cleanliness is required, but protective coatings or linings are not immediately applied. (Paragraphs A1 and A2 of Appendix A provide additional information.) Waterjet cleaning does not establish but may reveal

30、 an existing surface profile on a metallic substrate. If the existing surface profile is not acceptable for subsequent coating application, alternative surface preparation methods to create the required surface profile must be considered. (Paragraph A3 of Appendix A provides additional information.)

31、 1.1.1 Clean to Bare Substrate (WJ-1) is the waterjet cleaning equivalent to the International Organization for Standardization (ISO)(1) 8501-12 degree of cleanliness Sa 3, cleaning to bare metal. ISO 8501-43 notes the use of various common terms for methods of waterjet cleaning: water jetting, wate

32、r blast cleaning, hydrojetting, aquajetting, hydroblasting, aquablasting, and “cleaning by directing a jet of pressurized water onto the surface to be cleaned.” 1.1.2 Within the hierarchy of degrees of surface cleanliness achieved by waterjet cleaning, Clean to Bare Substrate (WJ-1) is intended to b

33、e similar to the degree of surface cleanliness of NACE No. 1/SSPC-SP 5,4 except that stains are permitted to remain on the surface. 1.2 Although carbon steel is the metallic substrate most frequently cleaned in the field using waterjetting technology, waterjet cleaning may be used on metallic substr

34、ates other than carbon steel, including other ferrous substrates such as alloy steels, stainless steels, ductile iron, and cast irons, nonferrous substrates such as aluminum, and copper alloys such as bronze. For convenience, the written definitions of the degrees of surface cleanliness of the metal

35、lic substrate use the general term “rust and other corrosion products.” The term “rust” is intended to apply to carbon steel substrates and the term “other corrosion products” (such as surface oxides) is intended to apply to metallic substrates other than carbon steel that are being waterjet cleaned

36、. “Flash rust” is an oxidation product that forms as a wetted carbon steel substrate dries. The visual guides and comparators referenced for cleanliness and flash rust only illustrate carbon steel substrates. 1.3 This standard does not address surface preparation of concrete. Information on surface

37、preparation of concrete can be found in NACE No. 6/SSPC-SP 13.5 1.4 This standard is limited to requirements for visible surface contaminants. Information on nonvisible contamination can be found in Paragraph A8 of Appendix A. _ Section 2: Definitions 2.1 Clean to Bare Substrate (WJ-1): A metal surf

38、ace after Clean to Bare Substrate, when viewed without magnification, shall have a matte (dull, mottled) finish and shall be free of all visible oil, grease, dirt, rust and other corrosion products, previous coatings, mill scale, and foreign matter. 2.1.1 Thin films of mill scale, rust and other cor

39、rosion products, and coating are not allowed. (Paragraphs A4 and A5 provide additional information). 2.1.2 The gray to brown-black discoloration remaining on corroded and pitted carbon steel that cannot be removed by further waterjet cleaning is allowed. 2.1.3 NACE VIS 7/SSPC-VIS 46 or other visual

40、guide or comparator may be specified to supplement the written definition. In any dispute, the written standard shall take precedence over the visual guide or comparator. (Paragraph A6 of Appendix A provides additional information.) _ (1) International Organization for Standardization (ISO), 1 ch. d

41、e la Voie-Creuse, Case postale 56, CH-1211 Geneva 20, Switzerland. NACE WJ-1/SSPC-SP WJ-1 2 NACE International _ Section 3: Additional Technical Considerations 3.1 Flash Rust Flash rust is an additional consideration when a carbon steel substrate is subjected to waterjet cleaning. Gray or brown-blac

42、k discoloration remaining in the pits of waterjet cleaned carbon steel is not the same as flash rust. Metals other than carbon steel can manifest discoloration as well. Degrees of flash rust may be qualitatively described as follows: 3.1.1 No flash rust: A carbon steel surface that, when viewed with

43、out magnification, exhibits no visible flash rust. 3.1.2 Light (L) flash rusted surface: A carbon steel surface that, when viewed without magnification, exhibits small quantities of a rust layer through which the carbon steel substrate may be observed. The rust or discoloration may be evenly distrib

44、uted or present in patches, but it is tightly adherent and not easily removed by lightly wiping with a cloth. 3.1.3 Moderate (M) flash rusted surface: A carbon steel surface that, when viewed without magnification, exhibits a layer of rust that obscures the original carbon steel surface. The rust la

45、yer may be evenly distributed or present in patches, but it is reasonably well adherent and leaves light marks on a cloth that is lightly wiped over the surface. 3.1.4 Heavy (H) flash rusted surface: A carbon steel surface that, when viewed without magnification, exhibits a layer of heavy rust that

46、hides the original carbon steel surface completely. The rust may be evenly distributed or present in patches, but it is loosely adherent, easily comes off, and leaves significant marks on a cloth that is lightly wiped over the surface. (Paragraphs A6, A9, and A10 of Appendix A provide additional inf

47、ormation. Appendix B provides additional information on methods of assessing the degree of flash rust.) 3.2 Appearance Variations 3.2.1 Acceptable variations in appearance that do not affect the degree of surface cleanliness defined in Paragraph 2.1 include variations caused by composition of the me

48、tallic substrate, original surface condition, thickness of the metal, weld metal, mill or fabrication marks, heat treating, heat-affected zones, and differences resulting from the initial abrasive blast cleaning abrasives or the abrasive blast pattern if previously blast cleaned, or waterjet cleaning pattern. 3.2.1.1 Carbon steel surfaces cleaned by waterj