1、 - STD.BS1 BS EN IS0 12744-4-ENGL 1778 mi Lb24bb7 0738278 bbl BRITISH STANDARD Paints and varnishes - Corrosion protection of steel structures by protective paint systems - Part 4: mes of surface and surface preparation The European Standard EN IS0 12944-1.1998 has the status of a British Standard I
2、Cs 87.020; 91.080.10 BS EN IS0 12944-4 1998 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHI LAW STD BSI BS EN IS0 12744-4-ENGL 1998 1b24bb 0738279 5T8 BS EN IS0 1294441998 National foreword This British Standard is the English language version of EN IS0 12944-41998. It is identica
3、l with IS0 12944-4 1998. Together with the other seven parts of BS EN IS0 12944, it partidy supersedes BS 5493 1977 which is declared obsolescent. The UK participation in its preparation was entrusted to Technical Committee STI/27, Paint systems for metallic substrates, which has the responsibility
4、to: - aid enquirers to understand the tee - present to the responsible internationallEuropean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; - monitor related international and European developments and promulgate them in the UK. A list of
5、 organizations represented on this committee can be obtained on request to its secretary. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists nonnative references to international publications with their corresponding European pubiicat
6、ions. The British standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index“, or by using the “Find“ facility of the BSI Standards Electronic Catal
7、ogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comp
8、rises a front cover, an inside ront cover, the EN IS0 tite page, the EN IS0 foreword page, the IS0 title page, pages ii to v, a blank page, pages 1 to 21, two annex ZA pages and a back cover. This British Standard, having been prepared under the direction of the Sector Committee for Materials and Ch
9、emicals, was published under the authority of the Standards Committee and comes into effect on 15 November 1998 O BSI 1998 ISBN O 580 30347 O Amendments issued since publication Amd.No. ID - surfaces thermally sprayed with zinc, aluminium or their alloys; - hot-dipgalvanized surfaces; - zinc-electro
10、plated surfaces; - sherardized surfaces; - surfaces painted with prefabrication primer; - other painted surfaces. This part of IS0 12944 defines a number of surface preparation grades but does not specify any requirements for the condition of the substrate prior to surface preparation. Highly polish
11、ed surfaces and work-hardened surfaces are not covered by this part of IS0 12944. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of IS0 12944. At the time of publication, the editions indicated were valid. A
12、ll standards are subject to revision, and parties to agreements based on this pad of IS0 12944 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and IS0 maintain registers of currently valid international Standards. IS
13、0 1461 :-I), Hot dip galvanized coatings on fabricated ferrous products - Specifications. IS0 2063:1991, Metallic and other inorganic coatings - Thermal spraying - Zinc, aluminium and their alloys. IS0 2409:1992, Paints and varnishes - Cross-cut test. 1) To be published. (Revision of IS0 1459:1973 a
14、nd IS0 1461:1973) 1 STD-BSI BS EN IS0 12744-4-NGL 1978 Lb24bb7 U730308 330 EN IS0 12944-4:1998 IS0 4628-1 ; 1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantity and size of common types of defect - Part 1: General Principles and rating schemes
15、. IS0 4628-2:1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantity and size of common types of defect - Part 2: Designation of degree of blistering. IS0 4628-3:1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designati
16、on of intensity, quantity and size of common types of defect - Part 3: Designation of degree of rusting. IS0 4628-4:1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantify and size of common types of defect - Part 4: Designation of degree of crac
17、king. IS0 4628431 982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantity and size of common types of defect - Part 5: Designation of degree of flaking. IS0 4628-6:1990, Paint and varnishes - Evaluation of degradation of paint coatings - Designati
18、on of intensity, quantity and size of common types of defect - Part 6: Rating of degree of chalking by tape method. IS0 8501 -1 :1988, Preparation of steel substrates before application of paints and related products - Visual assessrnent of surface cleanliness - Part 7: Rust grades and preparation g
19、rades of uncoated steel substrates and steel substrates after overall removal of previous coatings. Informative Supplement to IS0 8501 -1 :1988, Representative photographic examples of the change of appearance imparted to steel when blast-cleaned with different abrasives. IS0 8501 -2:1994, Preparati
20、on of steel substrates before application of paints and related products - Visual assessment of surface cleanliness - Part 2: Preparation grades of previously coated steel substrates after localized removal of previous coatings. ISOTTR 8502-1 :1991, Preparation of steel Substrates before application
21、 of paints and related products - Tests for the assessment of surface cleanliness - Part 1: Field test for soluble iron corrosion products. IS0 8502-2:1992, Preparation of steel substrates before application of paints and related products - Tests for the assessment of surface cleanliness - Part 2: L
22、aboratory determination of chloride on cleaned surfaces. IS0 8502-3:1992, Preparation of steel substrates before application of paints and related products - Tests for the assessment of surface cleanliness - Part 3: Assessment of dust on steel surfaces prepared for painting (pressure- sensitive tape
23、 method). IS0 8502-4:1993, Preparation of steel substrates before application of paints and related products - Tests for the assessment of surface cleanliness - Part 4: Guidance on the estimation of the probability of condensation prior to paint application. IS0 8503-1 :1988, Preparation of steel su
24、bstrates before application of paints and related products - Surface roughness characteristics of blast-cleaned steel substrates - Part 1: Specifications and definitions for IS0 surface profile comparators for the assessment of abrasive blast-cleaned surfaces. IS0 8503-2:1988, Preparation of steel s
25、ubstrates before application of paints and related products - Surface roughness characteristics of blast-cleaned steel substrates - Part 2: Method for the grading of surface profile of abrasive blast-cleaned steel - Comparator procedure. IS0 8504-1 :1992, Preparation of steel substrates before appli
26、cation of paints and related products - Surface preparation methods - Part 1: General principles. IS0 8504-2:1992, Preparation of steel substrates before application of paints and related products - Surface preparation methods - Part 2: Abrasive blast-cleaning. IS0 8504-3:1993, Preparation of steel
27、substrates before application of paints and related products - Surface preparation methods - Part 3: Hand- and power-tool cleaning. 2 STD-BSI BS EN IS0 229qq-Y-ENGL 1998 Lb24bbY 0738309 277 D EN IS0 12944-4:1998 IS0 1 11 24-1 :1993, Preparation of steel substrates before application of paints and re
28、lated products - Specifications for metallic blast-cleaning abrasives - Part 1: General introduction and classification. IS0 1 1 124-2:1993, Preparation of steel substrates before application of paints and related products - Specifications for metallic blast-cleaning abrasives - Part 2: Chilled-iron
29、 grit. IS0 1 1 124-3:1993, Preparation of steel substrates before application of paints and related products - Specifications for metallic blast-cleaning abrasives - Part 3: High-carbon cast-steel shot and grit. IS0 1 11 24-4:1993, Preparation of steel substrates before application of paints and rel
30、ated products - Specifications for metallic blast-cleaning abrasives - Part 4: Low-carbon cast-steel shot. IS0 1 1 126-1 :1993, Preparation of steel substrates before application of paints and related products - Specifications for non-metallic blast-cleaning abrasives - Part 1: General introduction
31、and classification. IS0 11 126-3:1993, Preparation of steel substrates before application of paints and related products - Specifications for non-metallic blast-cleaning abrasives - Part 3: Copper refinery slag. IS0 1 1 126-4: 1993, Preparation of steel substrates before application of paints and re
32、lated products - Specifications for non-metallic blast-cleaning abrasives - Part 4: Coal furnace slag. IS0 11 126-51 993, Preparation of steel substrates before application of paints and related products - Specifications for non-metallic blast-cleaning abrasives - Part 5: Nickel refinery slag. IS0 1
33、1 126-6:1993, Preparation of steel substrates before application of paints and related products - Specifications for non-metallic blast-cleaning abrasives - Part 6: Iron furnace slag. IS0 11 126-7:1995, Preparation of steel substrates before application of paints and related products - Specification
34、s for non-metallic blast-cleaning abrasives - Part 7: Fused aluminium oxide. IS0 11 126-8:1993, Preparation of steel substrates before application of paints and related products - Specifications for non-metallic blast-cleaning abrasives - Part 8: Olivine sand. IS0 12944-1 :1998, Paints and varnishes
35、 - Corrosion protection of steel structures by protective paint systems - Part 1: General introduction. EN 1 0238: 1 996, Automatically blast-cleaned and automatically prefabrication primed structural steel products. 3 Definitions For the purposes of this patt of IS0 12944, the following definitions
36、 apply in addition to those given in IS0 12944-1. 3.1 abrasive blast-cleaning: The impingement of a high-kinetic-energy stream of blast-cleaning abrasive on to the surface to be prepared. 3.2 blast-cleaning abrasive: A solid material intended to be used for abrasive blast-cleaning. IS0 11 124-1 ; IS
37、0 11 126-11 3.3 dust: Loose particulate matter present on a steel surface prepared for painting, arising from blast-cleaning or other surface preparation processes, or resulting from the action of the environment. IS0 8502-31 3.4 dew point: The temperature at which moisture in the air will condense
38、out on to a solid surface. See IS0 8502-4. 3.5 flash rusting: Slight rust formation on a prepared steel surface soon after preparation. 3.6 grit: Particles that are predominantly angular, that have fractured faces and sharp edges and that are less than half-round in shape. IS0 1 11 24-1 ; IS0 1 11 2
39、6-11 3 EN IS0 12944-41998 3.7 mill scale: The heavy oxide layer formed during hot fabrication or heat treatment of steel. 3.8 rust: Visible corrosion products consisting, in the case of ferrous metals, mainly of hydrated iron oxides. 3.9 shot: Particles that are predominantly round, that have a leng
40、th of less than twice the maximum particle width and that do not have edges, broken faces or other sharp surface defects. IS0 11 124-1; IS0 11 126-11 3.10 substrate: The surface to which the coating material has been applied or is to be applied. EN 971-11 3.1 1 surface preparation: Any method of pre
41、paring a surface for coating. 3.12 white rust: White to dark grey corrosion products on zinc-coated surfaces. 4 General The primary objective of surface preparation is to ensure the removal of deleterious matter and to obtain a surface that permits satisfactory adhesion of the priming paint to the s
42、teel. It will also assist in reducing the amounts of contaminants that initiate corrosion. It is stressed that there is a very wide variation in the condition of steel surfaces requiring cleaning prior to painting. This particularly applies to maintenance of an already coated structure. The age of t
43、he structure and its location, the quality of the previous surface, the performance of the existing coating system and the extent of breakdown, the type and severity of previous and future corrosion environments, and the intended new coating system all influence the amount of preparation required. W
44、hen selecting a surface preparation method, it is necessary to consider the preparation grade required to give a level of surface cleanliness and, if required, a surface profile (roughness) appropriate to the coating system to be applied to the steel surface. Since the cost of surface preparation is
45、 usually in proportion to the level of cleanliness, a preparation grade appropriate to the purpose and type of coating system or a coating system appropriate to the preparation grade which can be achieved should be chosen. Personnel carrying out surface preparation work shall have suitable equipment
46、 and sufficient technical knowledge of the processes involved to enable them to carry out the work in accordance with the required specification. All relevant health and safety regulations shall be observed. It is important that the surfaces to be treated are readily accessible and sufficiently illu
47、minated. All surface preparation work shall be properly supewised and inspected. If the specified preparation grade has not been achieved by the preparation method selected or when the condition of the prepared curface has subsequently changed before the application of the coating system, relevant p
48、arts of the procedure shall be repeated so as to obtain the specified preparation grade. Details regarding the preliminary treatment of welds, the removal of weld spatter and removal of burrs and other sharp edges shall be specified. These measures should normally be taken in connection with the man
49、ufacturing process before the surface preparation. For further details, see IS0 8504-1. 5 Types of surface to be prepared The surfaces to be prepared can be divided into the following: 5.1 Uncoated surfaces Uncoated surfaces consist of bare steel, which may be covered by mill scale or rust and other contaminants. They shall be assessed in accordance with IS0 8501 -1 (rust grades A, B, C and D). 4 STD.BSI BS EN IS0 12q4-4-ENGL 2798 fb2YbbY Cl7383LL 925 6 EN IS0 12944-4:1998 5.2 Metal-coated surfaces 5.2.1 Thermally sprayed surfaces Thermally sprayed surfaces consist of s
