1、SSPC-SP 16April 1, 20101SSPC: The Society for Protective CoatingsSURFACE PREPARATION SPECIFICATIONSSPC-SP 16Brush-Off Blast Cleaning of Coated and Uncoated Galvanized Steel, Stainless Steels, and Non-Ferrous MetalsForewordThis standard covers surface preparation of coated or uncoated metal surfaces
2、other than carbon steel prior to the application of a protective coating system. Surface preparation using this standard is used to uniformly roughen and clean the bare substrate and to roughen the surface of intact coatings on these metals prior to coating application. Substrates that may be prepar
3、ed by this method include, but are not limited to, galvanized surfaces, stainless steel, copper, aluminum, and brass. For the purpose of this standard, the zinc metal layer of hot-dip galvanized steel is considered to be the substrate, rather than the underlying steel. This standard is not to be use
4、d for cleaning coated or uncoated carbon steel substrates. Five different standards are available for cleaning carbon steel: White Metal Blast Cleaning1, Near-White Metal Blast Cleaning2, Commercial Blast Cleaning3, Industrial Blast Cleaning4, and Brush-Off Blast Cleaning5. This standard is intended
5、 for use by coating specifiers, applicators, inspectors, or others who may be responsible for defining a standard degree of surface cleanliness.This standard represents a degree of cleaning that is similar to that defined for carbon steel substrates in SSPC-SP7/NACE No. 4 except that a minimum surfa
6、ce profile depth on the bare metal surface is required. 1. Scope1.1 This standard covers the requirements for brush-off blast cleaning of uncoated or coated metal surfaces other than carbon steel by the use of abrasives. These requirements include visual verification of the end condition of the surf
7、ace and materials and procedures necessary to achieve and verify the end condition. 1.2 Information about the function of brush-off blast cleaning as defined in SP 16 is in Paragraph A1 of Appendix A. 2. Definitions2.1 A brush-off blast cleaned non-ferrous metal surface, when viewed without magnific
8、ation, shall be free of all visible oil, grease, dirt, dust, metal oxides (corrosion products), and other foreign matter. Intact, tightly adherent coating is permitted to remain. A coating is considered tightly adherent if it cannot be removed by lifting with a dull putty knife. Bare metal substrate
9、s shall have a minimum profile of 19 microm-eters (0.75 mil). 2.1.1 The entire surface shall be subjected to the abra-sive blast to achieve the specified degree of cleaning and to produce a dense and uniform surface profile on the bare metal substrate. The peaks and valleys on the surface shall form
10、 a continuous pattern, leaving no smooth, unprofiled areas. Tightly adherent coating is permitted to remain. A coating is considered tightly adherent if it cannot be removed by lifting with a dull putty knife.2.1.2 Intact coatings that are present shall be roughened and cleaned as specified in the p
11、rocurement documents. If the surface profile is not specified in the procurement docu-ments, the abrasive selected shall roughen the cleaned surface to the degree required by the product data sheet for the coating to be applied.2.1.3 Immediately prior to coating application, the entire surface shall
12、 comply with the degree of cleaning as speci-fied herein.3. Associated Documents3.1 Documents cited in the mandatory sections of this standard include:Document TitleSSPC-SP 16Solvent CleaningASTM D 4285(1),7Standard Test Method for Indicat-ing Oil or Water in Compressed Air(1) ASTM International (AS
13、TM), 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959SSPC-SP 16April 1, 20102ASTM D 4417(2),8Standard Test Methods for Field Measurement of Surface Profile of Blast Cleaned SteelASTM D 71279Standard Test Method for Mea-surement of Surface Roughness of Abrasive Blast Cleaned Metal Surfaces Usi
14、ng a Portable Stylus InstrumentASTM D 739310Method for Indicating Oil in Abra-sives3.2 The latest issue, revision, or amendment of the docu-ments listed in Paragraph 3.1 in effect on the date of invitation to bid shall govern unless otherwise specified.3.3 If there is a conflict between the requirem
15、ents of any of the documents listed in Paragraph 3.1 and this standard, the requirements of this standard shall prevail.4. Procedures Before Brush-Off Blast Cleaning of Non-Ferrous Metal Surfaces4.1 Before blast cleaning of non-ferrous metal surfaces, visible deposits of oil, grease, or other contam
16、inants that would interfere with coating adhesion shall be removed in accordance with SSPC-SP 1 or other specified methods. 4.2 Surface imperfections shall be corrected to the extent specified in the procurement documents (project specifica-tions). Additional information on surface imperfections is
17、in Paragraph A2 of Appendix A. 4.3 Unique Requirements for Preparation of Galvanized Steel4.3.1 Before blast cleaning, galvanized surfaces shall be checked for the presence of “wet storage stain.” Blast cleaning shall not be used to remove wet storage stain. The “dwell time” necessary for the blast
18、stream to remove wet storage stain can damage the galvanized surface. Additional information on the removal of wet storage stain is in Paragraph A3 of Appendix A. Additional information on blast cleaning galvanized steel is in Appendix A9.4.3.2 Unless written documentation exists to confirm that a g
19、alvanized surface is known to be free of chromates or other passivating treatments, representative areas of galvanized surfaces that will be coated shall be tested as described in Section 4.3.3 for the presence of chromates or other passi-vating treatments before brush-off blast cleaning is performe
20、d. If chromates or other passivating treatments are detected, the surface shall be retested after blast cleaning to confirm complete removal. OSHA requirements for worker protection from toxic metals may apply. Additional information on heavy metal toxicity is in Paragraph A4 of Appendix A. (2)Altho
21、ugh ASTM D 4417 is written for blast-cleaned steel, the methods are suitable for use on non-ferrous metals.4.3.3 Test for Presence of Passivating Treatments on Galvanizing (e.g., Chromating): “Chromating“ refers to the treatment of galvanized parts to prevent the occurrence of wet storage stain. Mos
22、t sheet metal and coil stock used to fabricate decking and curtain wall receives chromating treatments. The presence of chromates or other passivating treatments is detected by using a solution of copper sulfate, with the following procedure:Ensure that surfaces are free of any visible oxidation 1.
23、or oxidation by-productsPrepare the solution by dissolving 2 grams of copper 2. sulfate crystals in 100 ml of deionized water. Mark off three adjacent areas on the galvanized part, 3. approximately 6.45 cm2(1 inch2) Leave one area untouched, solvent wash the second 4. and third areas, and also thoro
24、ughly sand the third area using emery paper. Using an eyedropper or pipette, saturate a cotton 5. swab with the copper sulfate solution and apply to all three areas, or apply the solution directly to the three areas.If all three areas turn black immediately, there is no passivation on the surface. I
25、f the first area does not turn black within 10 seconds and the second and third areas turn black immedi-ately, there is no passivation on the surface with the possible exception of light oil. If the first and second areas do not turn black within 10 seconds and the third area turns immediately, a pa
26、ssivator of some type is present.5. Blast Cleaning Methods and Operation5.1 Clean, dry compressed air shall be used for nozzle blasting. Cleanliness of the compressed air shall be verified in accordance with the procedure described in ASTM D 4285. Moisture separators, oil separators, traps, or other
27、 equipment may be necessary to achieve this requirement. 5.2 Any of the following methods of surface preparation may be used to brush-off blast clean a non-ferrous metal substrate, but the presence of toxic metals in the abrasives or coating being removed can place restrictions on the methods of cle
28、aning permitted. The chosen method shall comply with all applicable regulations.5.2.1 Dry abrasive blasting using compressed air, blast nozzles, and abrasive.5.2.2 Dry abrasive blasting using a closed-cycle, recir-culating abrasive system with compressed air, blast nozzle, and abrasive, with or with
29、out vacuum for dust and abrasive recovery.5.2.3 Dry abrasive blasting using a closed-cycle, recircu-lating abrasive system with centrifugal wheels and abrasive. SSPC-SP 16April 1, 201035.2.4 When specified, other methods of surface preparation (such as wet abrasive blast cleaning) may be used to bru
30、sh-off blast clean non-ferrous metal surfaces. Additional information on cleaning soft and thin substrates is in Paragraphs A5, A6, and A7 of Appendix A. Additional information on the use of wet abrasive blast cleaning to clean galvanized surfaces is in Paragraph A9.3 of Appendix A.6. Abrasives for
31、Brush-Off Blast Cleaning of Non-Ferrous Metal Substrates6.1 The selection of abrasive size and type shall be based on the type, grade, and surface condition of the surface to be cleaned, the type of blast cleaning system used, the finished surface to be produced (cleanliness and surface profile roug
32、h-ness), and whether the abrasive will be recycled.6.2 The cleanliness and size of recycled abrasives shall be maintained to ensure compliance with this standard.6.3 The blast cleaning abrasive shall be dry and free of oil and grease, as determined by ASTM D 7393.6.4 The abrasive shall comply with a
33、ny limitations or special requirements stipulated by the procurement documents. Abrasive embedment and abrasives containing contaminants may not be acceptable for some service requirements. Addi-tional information on abrasive selection is in Paragraphs A8 and A8.1 of Appendix A.6.5 The abrasive mate
34、rial shall produce a dense and uniform profile acceptable for application of the intended coating. After cleaning, the cleaned metal surface shall have a minimum 19-micrometer (0.75 mil) profile, measured in accordance with ASTM D 4417 or ASTM D 7127. If present, intact tightly adherent coating shal
35、l be roughened as specified in the procurement documents (project specification). If the surface profile is not specified in the procurement documents, the abrasive selected shall roughen the cleaned surface to the degree required by the product data sheet for the coating to be applied.7. Procedures
36、 Following Brush-Off Blast Cleaning and Immediately Prior to Coating 7.1 Visible deposits of oil, grease, or other contaminants shall be removed as required by SSPC-SP 1, or as specified. 7.2 Dust, dirt and loose residues shall be removed from prepared surfaces by brushing; blowing off with clean, d
37、ry air; vacuum cleaning; or other specified methods. 7.3 Removal of chromates or other passivating treatments detected on galvanized surfaces (see Section 4.3.2) shall be confirmed before coating application, using the procedure in Section 4.3.3. 7.4 Immediately prior to coating application, the ent
38、ire surface shall comply with the degree of cleaning specified in this standard. 8. Disclaimer 8.1 While every precaution is taken to ensure that all information furnished in SSPC standards and specifications is as accurate, complete, and useful as possible, SSPC cannot assume responsibility nor inc
39、ur any obligation resulting from the use of any materials, coatings, or methods specified herein, or of the specification or standard itself.8.2 This specification does not attempt to address all problems concerning safety and health associated with its use. The user of this specification, as well a
40、s the user of all products or practices described herein, is responsible for insti-tuting appropriate health and safety practices and for ensuring compliance with all governmental regulations.References 1. SSPC-SP 5/NACE No. 1 (latest revision), White Metal Blast Cleaning (Pittsburgh, PA: SSPC, and
41、Houston, TX: NACE)2. SSPC-SP 10/NACE No. 2 (latest revision), Near-White Metal Blast Cleaning (Pittsburgh, PA: SSPC, and Houston, TX: NACE)3. SSPC-SP 6/NACE No. 3 (latest revision), Commercial Blast Cleaning (Pittsburgh, PA: SSPC, and Houston, TX: NACE)4. SSPC-SP 14/NACE No. 8 (latest revision), Ind
42、ustrial Blast Cleaning (Pittsburgh, PA: SSPC, and Houston, TX: NACE)5. SSPC-SP 7/NACE No. 4 (latest revision), Brush-Off Blast Cleaning (Pittsburgh, PA: SSPC, and Houston, TX: NACE)6. SSPC-SP 1 (latest revision), Solvent Cleaning (Pitts-burgh, PA: SSPC).7. ASTM D 4285 (latest revision), Standard Tes
43、t Method for Indicating Oil or Water in Compressed Air (West Conshohocken, PA: ASTM International).8. ASTM D 4417 (latest revision), Standard Test Methods for Field Measurement of Surface Profile of Blast Cleaned Steel (West Conshohocken, PA: ASTM International)9. ASTM D 7127 (latest revision), Stan
44、dard Test Method for Measurement of Surface Roughness of Abrasive Blast Cleaned Metal Surfaces Using a Portable Stylus Instru-ment (West Conshohocken, PA: ASTM International) 10. ASTM D 7393 (latest revision) Method for Indicating Oil in Abrasive11. Code of Federal Regulations, Title 29 Part 1926.11
45、26 (Chromium VI)12. ASTM B 6 (latest revision), Standard Specification for Zinc (West Conshohocken, PA: ASTM International)13. Code of Federal Regulations, Title 29 Part 1926.62 (Lead) SSPC-SP 16April 1, 2010414. ASTM D 1730 (latest revision), Standard Practices for Preparation of Aluminum and Alumi
46、num-Alloy Surfaces for Painting (West Conshohocken, PA: ASTM International)15. SSPC-SP COM (latest revision), Surface Preparation Commentary for Steel and Concrete Substrates (Pitts-burgh, PA: SSPC)16 SSPC-AB 1 (latest revision), Mineral and Slag Abrasives (Pittsburgh, PA: SSPC).17 SSPC-AB 2 (latest
47、 revision), Cleanliness of Recycled Ferrous Metallic Abrasives (Pittsburgh, PA: SSPC).18. SSPC-AB 3 (latest revision), Ferrous Metallic Abrasives (Pittsburgh, PA: SSPC).19. SSPC-AB 4 (latest revision), Recyclable Encapsulated Abrasive Media (Pittsburgh PA: SSPC).20. ASTM A 123 (latest revision), Sta
48、ndard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Prod-ucts (West Conshohocken, PA: ASTM International)21. ASTM A 153 (latest revision), Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware (West Conshohocken, PA: ASTM International)22. ASTM A 780 (latest re
49、vision), Standard Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized Coatings (West Conshohocken, PA: ASTM International)23. ASTM D 6386 (latest revision), Standard Practice for Preparation of Zinc (Hot-Dip Galvanized) Coated Iron and Steel Product and Hardware Surfaces for Painting (West Conshohocken, PA: ASTM International) Nonmandatory Appendix A: Explanatory Notes A1 FUNCTION: This standard provides a degree of cleaning for non-ferrous metal substrates comparable to or greater than brush-off blast cleaning (SSPC-SP 7/NACE No. 4) of carbon steel. It is used to clean a
