NACE NO 1-1994 Joint Surface Preparation Standard White Metal Blast Cleaning (Item No 21065).pdf

1、 Item No. 21065 Joint Surface Preparation Standard NACE No. 1/SSPC-SP 5 White Metal Blast Cleaning This NACE International (NACE)/The Society for Protective Coatings (SSPC) standard represents a consensus of those individual members who have reviewed this document, its scope, and provisions. It is i

2、ntended to aid the manufacturer, the consumer, and the general public. 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 addressed in this standard. Not

3、hing contained in this NACE/SSPC standard is to 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

4、Letters Patent. This standard represents current technology and should in no way be interpreted as a restriction 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 thi

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

6、the issuance of interpretations by individual volunteers. Users of this NACE/SSPC 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/SSPC standard

7、may not necessarily address 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 are also responsible for establishing appropriate health, sa

8、fety, and environmental protection 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 standards are subject to periodic review, and

9、 may be revised or withdrawn at any time in accordance with technical committee procedures. The user is cautioned to obtain the latest edition. 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. Rea

10、ffirmed 2006-09-13 Reaffirmed 1999-09-07 Approved October 1994 ISBN 1-57590-107-2 2006, SSPC: The Society for Protective Coatings and NACE International NACE International 1440 South Creek Dr. Houston, TX 77084-4906 (telephone +1 281/228-6200) SSPC: The Society for Protective Coatings 40 24th Street

11、, Sixth Floor Pittsburgh, PA 15222 (telephone +1 412/281-2331) Printed by NACE InternationalNACE No. 1/SSPC-SP 5 NACE International i _ Foreword This joint standard covers the use of blast cleaning abrasives to achieve a defined degree of cleaning of steel surfaces prior to the application of a prot

12、ective coating or lining system. This standard is intended for use by coating or lining specifiers, applicators, inspectors, or others who may be responsible for defining a standard degree of surface cleanliness. The focus of this standard is white metal blast cleaning. Near-white metal blast cleani

13、ng, commercial blast cleaning, industrial blast cleaning, and brush-off blast cleaning are addressed in separate standards. White metal blast cleaning provides a greater degree of cleaning than near-white metal blast cleaning (NACE No. 2/SSPC-SP 101). The difference between a white metal blast and a

14、 near-white metal blast is that a white metal blast removes all of the coating, mill scale, rust, oxides, corrosion products, and other foreign matter from the surface. Near-white metal blasting allows light shadows, slight streaks, or minor discolorations caused by stains of rust, stains of mill sc

15、ale, or stains of previously applied coating to remain on no more than 5 percent of each unit area of surface as defined in NACE No. 2/SSPC-SP 10. This joint standard was originally prepared in 1994 and reaffirmed in 1999 by the SSPC/NACE Task Group (TG) A on Surface Preparation by Abrasive Blast Cl

16、eaning. This joint TG includes members of both the SSPC Surface Preparation Committee and the NACE Unit Committee T-6G on Surface Preparation. It was reaffirmed in 2006 by NACE Specific Technology Group (STG) 04, Protective Coatings and Linings: Surface Preparation, and the SSPC Surface Preparation

17、Committee. In NACE/SSPC standards, the terms shall, must, should, and may are used in accordance with Paragraph 2.2.1.8 of the Agreement Between NACE International and SSPC: The Society for Protective Coatings. The terms shall and must are used to state mandatory requirements. The term should is use

18、d to state something considered good and is recommended but is not mandatory. The term may is used to state something considered optional. _ NACE No. 1/SSPC-SP 5 ii NACE International _ Joint Surface Preparation Standard NACE No. 1/SSPC-SP 5 White Metal Blast Cleaning Contents 1. General 1 2. Defini

19、tions 1 3. Associated Documents 1 4. Procedures Before Cleaning 1 5. Blast Cleaning Methods and Operation . 2 6. Blast Cleaning Abrasives . 2 7. Procedures Following Blast Cleaning and Immediately Prior to Coating 2 8. Inspection . 3 9. Safety and Environmental Requirements 3 10. Comments (Nonmandat

20、ory) 3 References 3 Appendix A: Explanatory Notes (Nonmandatory). 4 _ NACE No. 1/SSPC-SP 5 NACE International 1 _ Section 1: General 1.1 This joint standard covers the requirements for white metal blast cleaning of uncoated or coated steel surfaces by the use of abrasives. These requirements include

21、 the end condition of the surface and materials and procedures necessary to achieve and verify the end condition. 1.2 The mandatory requirements are described in Sections 1 to 9. Section 10, “Comments,” and Appendix A,“Explanatory Notes,” are not mandatory requirements of this standard. 1.3 Informat

22、ion about the function of white metal blast cleaning is in Paragraph A1 of Appendix A. 1.4 Information about use of this standard in maintenance coating work is in Paragraph A2 of Appendix A. _ Section 2: Definitions 2.1 White Metal Blast Cleaned Surface: A white metal blast cleaned surface, when vi

23、ewed without magnification, shall be free of all visible oil, grease, dust, dirt, mill scale, rust, coating, oxides, corrosion products, and other foreign matter. 2.1.1 Acceptable variations in appearance that do not affect surface cleanliness as defined in Paragraph 2.1 include variations caused by

24、 type of steel, original surface condition, thickness of the steel, weld metal, mill or fabrication marks, heat treating, heat-affected zones, blasting abrasives, and differences because of blasting technique. 2.1.2 SSPC-VIS 12may be specified to supplement the written definition. In any dispute, th

25、e written definition set forth in this standard shall take precedence over reference photographs and comparators. Additional information on reference photographs and comparators is in Paragraph A3 of Appendix A. _ Section 3: Associated Documents 3.1 The latest issue, revision, or amendment of the do

26、cuments listed in Paragraph 3.3 in effect on the date of invitation to bid shall govern unless otherwise specified. 3.2 If there is a conflict between the requirements of any of the documents listed in Paragraph 3.3 and this standard, the requirements of this standard shall prevail. 3.3 Documents ci

27、ted in the mandatory sections of this standard include: Document Title SSPC-AB 13Mineral and Slag Abrasives SSPC-AB 24Cleanliness of Recycled Ferrous Metallic Abrasives SSPC-AB 35Ferrous Metallic Abrasives SSPC-SP 16Solvent Cleaning SSPC-VIS 1 Guide and Reference Photographs for Steel Surfaces Prepa

28、red by Dry Abrasive Blast Cleaning _ Section 4: Procedures Before Cleaning 4.1 Before blast cleaning, visible deposits of oil, grease, or other contaminants shall be removed in accordance with SSPC-SP 1 or other agreed-upon methods. 4.2 Before blast cleaning, surface imperfections such as sharp fins

29、, sharp edges, weld spatter, or burning slag should be removed from the surface to the extent required by the procurement documents (project specification). Additional information on surface imperfections is in Paragraph A4 of Appendix A. 4.3 If reference photographs or comparators are specified to

30、supplement the written standard, the condition of the steel prior to blast cleaning should be determined before the blasting commences. Additional information on reference photographs and comparators is in Paragraph A3 of Appendix A. NACE No. 1/SSPC-SP 5 2 NACE International _ Section 5: Blast Clean

31、ing Methods and Operation 5.1 Clean, dry compressed air shall be used for nozzle blasting. Moisture separators, oil separators, traps, or other equipment may be necessary to achieve this requirement. 5.2 Any of the following methods of surface preparation may be used to achieve a white metal blast c

32、leaned surface: 5.2.1 Dry abrasive blasting using compressed air, blast nozzles, and abrasive. 5.2.2 Dry abrasive blasting using a closed-cycle, recirculating abrasive system with compressed air, blast nozzle, and abrasive, with or without vacuum for dust and abrasive recovery. 5.2.3 Dry abrasive bl

33、asting using a closed-cycle, recirculating abrasive system with centrifugal wheels and abrasive. 5.3 Other methods of surface preparation (such as wet abrasive blast cleaning) may be used to achieve a white metal blast cleaned surface by mutual agreement between those responsible for establishing th

34、e requirements and those responsible for performing the work. Information on the use of inhibitors to prevent the formation of rust immediately after wet abrasive blast cleaning is in Paragraph A5 of Appendix A. _ Section 6: Blast Cleaning Abrasives 6.1 The selection of abrasive size and type shall

35、be based on the type, grade, and surface condition of the steel to be cleaned, the type of blast cleaning system used, the finished surface to be produced (cleanliness and surface profile roughness), and whether the abrasive will be recycled. 6.2 The cleanliness and size of recycled abrasives shall

36、be maintained to ensure compliance with this standard. 6.3 The blast cleaning abrasive shall be dry and free of oil, grease, and other contaminants as determined by the test methods found in SSPC-AB 1, SSPC-AB 2, and SSPC-AB 3. 6.4 Any limitations on the use of specific abrasives, the quantity of co

37、ntaminants, or the degree of allowable embedment shall be included in the procurement documents (project specification) covering the work, because abrasive embedment and abrasives containing contaminants may not be acceptable for some service requirements. Additional information on abrasive selectio

38、n is in Paragraph A6 of Appendix A. 6.5 When a coating is specified, the cleaned surface shall be roughened to a degree suitable for the specified coating system. Additional information on surface profile and the film thickness of coating applied over the surface profile is in Paragraphs A7 and A8 o

39、f Appendix A. _ Section 7: Procedures Following Blast Cleaning and Immediately Prior to Coating 7.1 Visible deposits of oil, grease, or other contaminants shall be removed according to SSPC-SP 1 or another method agreed upon by those parties responsible for establishing the requirements and those re

40、sponsible for performing the work. 7.2 Dust and loose residues shall be removed from prepared surfaces by brushing; blowing off with clean, dry air; vacuum cleaning; or other methods agreed upon by those responsible for establishing the requirements and those responsible for performing the work. 7.2

41、.1 The presence of toxic metals in the abrasives or coating being removed may place restrictions on the methods of cleaning permitted. The chosen method shall comply with all applicable regulations. 7.2.2 Moisture separators, oil separators, traps, or other equipment may be necessary to achieve clea

42、n, dry air. 7.3 After blast cleaning, any remaining surface imperfections (e.g., sharp fins, sharp edges, weld spatter, burning slag, scabs, slivers) shall be removed to the extent required by the procurement documents (project specification). Any damage to the surface profile resulting from the rem

43、oval of surface imperfections shall be corrected to meet the requirements of Paragraph 6.5. Additional information on surface imperfections is in Paragraph A4 of Appendix A. 7.4 Immediately prior to coating application, the entire surface shall comply with the degree of cleaning specified in this st

44、andard. Any visible rust that forms on the surface of NACE No. 1/SSPC-SP 5 NACE International 3 the steel after blast cleaning shall be removed by recleaning the rusted areas before coating. Information on chemical contamination, rust-back (rerusting), and the effect of dew point (surface condensati

45、on) is in Paragraphs A9, A10, and A11 of Appendix A. _ Section 8: Inspection 8.1 Work performed and materials supplied under this standard are subject to inspection by a representative of those responsible for establishing the requirements. Materials and work areas shall be accessible to the inspect

46、or. The procedures and times of inspection shall be as agreed upon by those responsible for establishing the requirements and those responsible for performing the work. 8.2 Conditions not complying with this standard shall be corrected. In the case of a dispute, an arbitration or settlement procedur

47、e established in the procurement documents (project specification) shall be followed. If no arbitration or settlement procedure is established, a procedure mutually agreeable to purchaser and supplier shall be used. 8.3 The procurement documents (project specification) should establish the responsibility for inspection and fo