1、SSPC-SP 15July 19, 2012Editorial Revisions November 11, 20131SSPC: The Society for Protective CoatingsSurface Preparation Standard No. 15Commercial Grade Power-Tool Cleaning1. Scope 1.1 This standard contains the requirements for power-tool cleaning steel to produce a commercial grade power-tool cle
2、aned steel surface having a minimum 25 micrometer (1.0 mil) surface profile.1.2 This standard is suitable where a roughened metal surface that is free of all visible oil, grease, dirt, rust, coating, mill scale, corrosion products, and other foreign matter except as noted in Section 2.2 is required,
3、 but where abrasive blasting is not feasible or permissible (see Notes 8.1 and 8.2).1.3 This standard differs from SSPC-SP 3, Power-Tool Cleaning, in that SSPC-SP 3 requires only the removal of loosely adherent materials, and contains no requirement to expose bare metal or to achieve a minimum surfa
4、ce profile.1.4 This standard differs from SSPC-SP 11, Power-Tool Cleaning to Bare Metal, in that SSPC-SP 11 does not allow stains to remain on the surface. 2. Definition2.1 A commercial grade power-tool cleaned steel surface, when viewed without magnification, shall be free of all visible oil, greas
5、e, dirt, rust, coating, mill scale, corrosion products, and other foreign matter, except as noted in Section 2.2 (see Notes 8.1 and 8.3).2.2 Random staining shall be limited to no more than 33 percent of each unit area of surface as defined in Section 2.3. Staining consists of light shadows, slight
6、streaks, or minor discolorations caused by stains of rust, stains of mill scale, or stains of previously applied coating. Trace amounts of coating and corrosion products are permitted to remain in the lower portions of pits if the original surface is pitted.2.3 Unit area for determining staining sha
7、ll be approxi-mately 5800 mm2(9 in2) (i.e., a square 76 x 76 mm 3 x 3 inches).2.4 Acceptable variations in appearance that do not affect surface cleanliness as defined in Section 2.1 and 2.2 include variations caused by type of steel, original surface condition, thickness of the steel, weld metal, m
8、ill or fabrication marks, heat treating, heat-affected zones, or the texture/features associated with the use of a particular power tool. 2.5 The surface profile shall be a minimum of 25 microm-eters (1.0 mil). The peaks and valleys on the prepared surface shall form a continuous pattern with no smo
9、oth, unprofiled areas. 2.6 The profile shall be measured in accordance with ASTM D 4417 Method B unless otherwise specified (see Notes 8.4, 8.5, and 8.6).12.7 Reference photographs of power-tool cleaned surfaces found in SSPC-VIS 3 are often used to supplement the written definition. In any dispute,
10、 the written definition set forth in this standard shall take precedence over reference photographs. Additional information on reference photographs is in Note 8.3.3. Referenced Standards 3.1 The latest issue, revision, or amendment of the refer-enced standards in effect on the date of invitation to
11、 bid shall govern unless otherwise specified. Standards marked with an asterisk (*) are referenced only in the Notes, which are not requirements of this standard.3.2 If there is a conflict between the requirements of any of the cited reference standards and this standard, the require-ments of this s
12、tandard shall prevail.3.3 SSPC STANDARDS:* PA 2 Procedure for Determining Compli-ance to Dry Coating Thickness RequirementsSP 1 Solvent CleaningSP 3 Power-Tool Cleaning SP 11 Power-Tool Cleaning to Bare Metal* SP 6 Commercial Blast CleaningVIS 3 Guide and Reference Photographs for Steel Surfaces Pre
13、pared by Power- and Hand-Tool Cleaning 1 Although ASTM D 4417 and ASTM D 7127 indicate in their titles that they describe methods intended for use on blast-cleaned steel, there is currently no method specifically designed for measurement of profile on steel surfaces prepared using power tools. Visua
14、l comparators used for ASTM D 4417 Method A represent surfaces prepared by abrasive blast cleaning and are inappropriate for comparison with power-tool cleaned surfaces. The replica tape used for ASTM D 4417 Method C cannot accurately measure the profile produced by some types of power-tool cleaning
15、 media. A test area prepared at the job site can be used to assess the suitability of media and profile measure-ment method for a project prior to full-scale production.SSPC-SP 15July 19, 2012Editorial Revisions November 11, 201323.4 ASTM INTERNATIONAL STANDARDS:2D 4285 Standard Test Method for Indi
16、-cating the Presence of Oil or Water in Compressed Air D 4417 Standard Test Methods for Field Measurement of Surface Profile of Blast Cleaned Steel* D 7127 Standard Test Method for Measure-ment of Surface Roughness of Abrasive Blast Cleaned Metal Surfaces Using a Portable Stylus Instrument4. Tools a
17、nd Methods for Commercial Grade Power-Tool Cleaning 4.1 POWER TOOLS: Any hand-held motorized tool on which the media described in Sections 4.1.1 and 4.1.2 are capable of being mounted in accordance with manufacturers instructions and that will produce a steel surface meeting the requirements of Sect
18、ions 2.1. 2.2, and 2.5 is acceptable (see Notes 8.7.1, 8.7.2, 8.8 and 8.9). Sections 4.1.1 and 4.1.2 describe the two main categories of power tools. It is possible for power tools to alter an existing surface profile.4.1.1 Grinding Tools: Grinding tools use media containing bonded abrasive grains t
19、o cut through corroded surfaces and include, but are not limited to, discs or wheels as described in Note 8.6.1. 4.1.2 Impact Tools: Impact tools use media that repeat-edly collide with the target surface and include, but are not limited to, various rotary and reciprocating devices as described in N
20、ote 8.6.2. 4.2 The use of several different power tools meeting the requirements of Sections 4.1, 4.1.1 and 4.1.2 is sometimes necessary to achieve a commercial grade power-tool cleaned surface meeting the requirements of Sections 2.1 and 2.2 (see Note 8.7 and subsections).4.3 If the procurement doc
21、uments require power-tool cleaning to prepare surfaces for subsequent coating, the edges of remaining intact coatings shall, unless otherwise specified, be feathered to improve the appearance of the repaired coating (see Note 8.2).5. Procedures Prior to Power-Tool Cleaning 5.1 Prior to power-tool cl
22、eaning, visible deposits of oil, grease, or other materials that may interfere with coating adhe-sion shall be removed in accordance with SSPC-SP 1 or other specified methods. 2 ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959. For referenced ASTM standards, visit the ASTM
23、 website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standards volume information, refer to the standards Docu-ment Summary page on the ASTM website.5.2 Surface imperfections such as slivers and laminations, sharp edges, weld spatter, or burning slag s
24、hall be removed from the surface to the extent specified by the procurement documents project specifications (see Note 8.10). 5.3 When air-driven tools are used, cleanliness of the compressed air shall be verified in accordance with the proce-dure described in ASTM D 4285.6. Procedures Following Pow
25、er-Tool Cleaning and Immediately Prior to Coating6.1 Visible deposits of oil, grease, or other contami-nants shall be removed in accordance with SSPC-SP 1 or as specified. 6.2 Dust and loose residues shall be removed from commercial grade power-tool cleaned (SSPC-SP 15) surfaces by brushing; blowing
26、 off with clean, dry air per Section 5.3; vacuum cleaning; or other methods established in the procure-ment documents (project specification).6.3 After power-tool cleaning, any remaining surface imperfections revealed by the processing in Section 5.2 (e.g., laminations, sharp edges, weld spatter, bu
27、rning slag, scabs, slivers) shall be removed to the extent required by the procure-ment documents (project specification). Any damage to the surface profile resulting from the removal of surface imperfec-tions shall be corrected to meet the requirements of Section 2.5 (see Note 8.10).6.4 Immediately
28、 prior to coating application, the entire surface to be coated shall comply with the requirements of Sections 2.1, 2.2, and 2.3 (see Notes 8.11 and 8.12).7. Disclaimer7.1 While every precaution is taken to ensure that all information furnished in SSPC standards and specifications is as accurate, com
29、plete, and useful as possible, SSPC cannot assume responsibility nor incur any obligation resulting from the use of any materials, coatings, or methods specified herein, or of the specification or standard itself.7.2 This standard does not attempt to address prob-lems concerning safety associated wi
30、th its use. The user of this standard, as well as the user of all products or practices described herein, is responsible for instituting appropriate health and safety practices and for ensuring compliance with all appropriate governmental regulations.8. NotesNotes are not requirements of this standa
31、rd.8.1 FUNCTION: The type of power-tool surface prepa-ration described in this standard removes tightly adherent material, producing a surface that is free from rust, mill scale, SSPC-SP 15July 19, 2012Editorial Revisions November 11, 20133and old coatings. The surface must also have a minimum 25-mi
32、crometer (1.0 mil) surface profile. Commercial Grade Power-Tool Cleaning produces a greater degree of cleaning than SSPC-SP 3, which does not remove adherent material, but a lesser degree of cleaning than SSPC-SP 11, which requires removal of all surface staining. Commercial Grade Power-Tool Cleanin
33、g may be considered for coatings that require a very clean surface, but where the extra effort required to remove all surface staining is not required.This standard is suitable where a roughened, cleaned surface is required, but where abrasive blasting is not feasible or permissible. The surfaces pr
34、epared according to this stan-dard should not be compared to surfaces cleaned by abrasive blast cleaning. Although this method produces surfaces that resemble SSPC-SP 6 (Commercial Blast Cleaning), with the exception of material allowed in pits, power-tool cleaned surfaces are not necessarily equiva
35、lent to surfaces produced by abrasive blast cleaning. The contracting parties should agree on the appropriateness of the finished surface to accept the specified coating system. Selection of power tools and cleaning media should be based on (1) the condition of the surface prior to surface preparati
36、on; (2) the extent of cleaning that is required; and (3) the surface profile required.The SSPC Surface Preparation Commentary (SSPC-SP COM) provides additional information on subjects related to power-tool cleaning. The recommendations contained in SSPC-SP COM are believed to represent good practice
37、, but are not to be considered requirements of this standard.8.2 MAINTENANCE AND REPAIR PAINTING: When this standard is used in maintenance painting, specific instruc-tions should be given on the extent of surface to be power-tool cleaned, including any additional requirements for retaining old pain
38、t, removing unsound paint, feathering and spot cleaning. 8.3 VISUAL GUIDES AND COMPARATORS: Note that the use of visual guides or comparators in conjunction with this standard is required only when they are specified in the procurement documents (project specification) covering the work. It is recom
39、mended, however, that the use of visual guides or comparators be made mandatory in the procurement documents. SSPC-VIS 3 provides a suitable comparative visual guide for SSPC-SP 3, SSPC-SP 11, and SSPC-SP 15. However, visual comparators for blast-cleaned steel (e.g., SSPC-VIS 1) are not suitable for
40、 assessing power-tool cleaned surfaces. Because power-tool cleaning is a time- and labor-intensive method of cleaning, it is advisable to prepare a test area of 1 x 1 sq meter (3 x 3 sq. ft.) for large areas or 30 x 30 cm (12 x 12 inch) for spot cleaning to an acceptable level agreed upon by the con
41、tracting parties, and cover it with a clear lacquer to save it as a standard during the power-tool cleaning operation. A 30 x 30 cm (12 x 12 inch) steel test plate can also be power-tool cleaned to an acceptable level and sealed to serve as a project standard. Alternatively, such a field standard co
42、uld be protected with a volatile corrosion inhibitor, tablet or impreg-nated paper, with or without a desiccant, and kept in a sealed plastic bag to permit examination of the surface profile.8.4 PROFILE: The profile created by any cleaning media depends on many factors, including the composition and
43、 hard-ness of the steel, the presence and depth of any pre-existing profile, and the hardness and thickness of any existing coating materials.The ability of various media to produce a profile or main-tain an existing profile depends upon physical characteristics such as hardness, angularity or sharp
44、ness, size,and mass; spacing; speed (velocity) of impact on the steel; and ability to fracture the coating material and alter the steel surface. The media indicated in Section 4.1.1 are capable of producing a profile of 12.5 micrometers (0.5 mil) on mild (struc-tural) steel, while the media in Secti
45、on 4.1.2 are capable of producing a profile of 25 micrometers (1.0 mil) and greater on mild steel. The same media may not be capable of producing the same profile depth in other steels, e.g., weathering steel, stainless steel, welds, et al. These capabilities are possible when the tools are used by
46、an experienced operator.Power tools are also capable of reducing existing deeper profiles by partial removal of the tops of the existing profiles, especially by grinding, sanding and the use of rotary flaps. In cases of excessive pressure or dwell period at a specific location, the power tools can c
47、ause sharp edges and cuts in the steel. Rotary power tools can cause a burnishing of profile previously imparted to steel or of the existing profile, thereby reducing that profile. Impact power tools can cause burrs and gouges.It is important to determine prior to the start of produc-tion if the pow
48、er tools to be used is capable of creating a profile that meets the requirement of the project specification or the manufacturers requirement for the specified coating. Concerns about the suitability of a tool to achieve the require-ments of this standard should be discussed in advance with the tool
49、 manufacturers technical representative.8.5 FILM THICKNESS: It is essential that ample coating be applied after power-tool cleaning to adequately cover the peaks of the surface profile. The dry film thickness above the peaks of the profile should equal the thickness needed for the desired protection. If the dry film thickness over the peaks is inadequate according to contract documents or manufactur-ers specifications, premature rust-through or failure will occur. The procedures in SSPC-PA 2 should be used to ensure that coating thickness is properly measured.8.6 SUITABLE TOOLS AND