1、INTERNATIONAL STANDARD NORME I NTERNATI O NALE M EXAYHAPOIH bl l? CTAHAAPT IS0 8501 -2 First edition Premire edition ilepsoe mnatie 1994-12-15 Preparation of steel substrates before application of paints and related products -Visual assessment of surface cleanliness - Part 2: Preparation grades of p
2、reviously coated steel substrates after localized removal of previous coatings Prparation des subjectiles dacier avant application de peintures et de produits assimils - valuation visuelle de la propret dun subjectile - Partie 2: Degrs de prparation des subjectiles dacier prcdemment revtus aprs dcap
3、age localis des couches Reference number Numero de rfrence IS0 8501-2:1994(E/F/R) HOMep CCblilKM CD IS0 1994 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and mi
4、crofilm, without permission in writing from the publisher. / Droits de reproduction rservs. Sauf prescription diffrente, aucune partie de cette publication ne peut etre reproduite ni utilise sous quelque forme que ce soit et par aucun procd, lectronique ou mcanique, y compris la photocopie et les mi
5、crofilms, sans laccord crit de Iditeur. International Organization for Standardization Case postale 56 CH-I211 Genve 20 Switzerland Printed in Sweden/lmprim en Sude. E Wezata 1995 IS0 8501 -2:1994( E/F/R) Foreword IS0 (the International Organization for Standardization) is a worldwide federation of
6、national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. Inte
7、rnational organizations, governmental and non- governmental, in liaison with ISO, also take part in the work. IS0 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical c
8、ommittees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard IS0 8501-2 was prepared by Technical Committee ISOPC 35, Paints and varnishes, Subcommittee SC 12, Prepara
9、tion of steel substrates before application of paints and related products. IS0501 consists at present of the following parts, under the general title Preparation of steel substrates before application of paints and related products - Visual assessment of surface cleanliness : - Part I: Rust grades
10、and preparation grades of uncoated steel substrates and of steel substrates after overall removal of previous coatings. - Informative Supplement to part 1: Representative photographic examples of the change of appearance imparted to steel when blast- cleaned with different abrasives. - Part 2: Prepa
11、ration grades of previously coated steel substrates after localized removal of previous coatings. - Part3: Preparation grades of welds, cut edges and surface imperfections. Annexes A to J form an integral part of this part of IS0 8501. ii - IS0 8501-2:1994(E/F/R) Avant-propos LISO (Organisation inte
12、rnationale de normalisation) est une fdration mondiale dorganismes nationaux de normalisation (comits membres de IISO). Llaboration des Normes internationales est en gnral confie aux comits techniques de IISO. Chaque comit membre intress par une tude a le droit de faire partie du comit technique cr
13、cet effet. Les organisations internationales, gouvernementales et non gouvernementales, en liaison avec IISO participent galement aux travaux. LISO collabore troitement avec la Commission lectrotechnique internationale (CEI) en ce qui concerne la normalisation lectrotechnique. Les projets de Normes
14、internationales adopts par les comits techniques sont soumis aux comits membres pour vote. Leur publication comme Normes internationales requiert lapprobation de 75 % au moins des comits membres votants. La Norme internationale IS0 8501-2 a t labore par le comit technique lSO/TC 35, Peintures et ver
15、nis, sous-comit SC 12, Prparation de subjectiles dacier avant application de peintures et de produits assimils. LISO 8501 comprend les parties suivantes, prsentes sous le titre gnral Prparation des subjectiles dacier avant application de peintures et de produits assimils - valuation visuelle de la p
16、ropret dun subjectile : - Partie I: Degrs de rouille et degrs de prparation des subjectiles dacier non recouverts et des subjectiles dacier aprh dcapage sur toute la surface des revtements prcdents. - Supplment informatif la partie 1: Exemples de clichs reprsentatifs du changement daspect communiqu
17、B lacier dcap avec des abrasifs diffrents. - Partie 2: Degrs de prparation des subjectiles dacier prcdemment revtus aprs dcapage localis des couchas. - Partie3: Degrs de prparation des soudures, artes de coupe et imperfections de surface. Les annexes A J font partie intgrante de la prsente partie de
18、 IISO 8501. iii IS0 8501 -2: 1994( E/F/R) iv INTERNATIONAL STANDARD IS0 8501-2:1994(E) Preparation 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 remov
19、al of previous coatings Introduction The performance of protective coatings of paint and related products applied to steel is significantly affected by the state of the steel surface immediately prior to painting. The principal factors that are known to influence this performance are a) the presence
20、 of rust and mill scale; b) the presence of surface contaminants, including salts, dust, oils and greases; c) the surface profile. International Standards IS0 8501, IS0 8502 and IS0 8503 have been prepared to provide methods of assessing these factors, while IS0 8504 provides guidance on the prepara
21、tion methods that are available for cleaning steel substrates, indicating the capabilities of each in attaining specified levels of cleanliness. These International Standards do not contain recommendations for the pro- tective coating systems to be applied to the steel surface. Neither do they conta
22、in recommendations for the surface quality requirements for specific situations even though surface quality can have a direct influence on the choice of protective coating to be applied and on its performance. Such recommendations are found in other documents such as national standards 1 IS0 8501 -2
23、:1994( E) and codes of practice. It will be necessary for the users of these International Standards to ensure that the qualities specified are - compatible and appropriate both for the environmental conditions to which the steel will be exposed and for the protective coating system to be used; - wi
24、thin the capability of the cleaning procedure specified. The four International Standards referred to above deal with the following aspects of preparation of steel substrates: IS0 8501 - Visual assessment of surface cleanliness; IS0 8502 - Tests for the assessment of surface cleanliness; IS0 8503 -
25、Surface roughness characteristics of blast-cleaned steel sub- strates; IS0 8504 - Surface preparation methods. Each of these International Standards is in turn divided into separate parts. This part of IS0 8501 supplements IS0 8501-1. It identifies certain degrees of visual cleanliness (designated a
26、s “preparation grades“) following surface preparation of steel surfaces after localized removal of previous paint coatings. These levels of visual cleanliness are related to the common methods of surface cleaning that are used prior to painting. The photographic examples for preparation grades P Sa
27、2% and P Ma have been taken from DIN 55 928, Part 4, Supplement 1 (August 1978) and Supplement 2 (January 19861, respectively. The basis of this part of IS0 8501 is the experience that complete removal of all previous paint coatings is not always necessary. This is especially true where maintenance
28、work is carried out at regular intervals. For localized removal to be preferred, the following conditions should be fulfilled: - the remaining intact coating should make a useful and durable contri- bution to the new corrosion protection system and be compatible with it; - during cleaning of locally
29、 corroded areas down to the substrate, the coatings on the surrounding areas should not be irreparably or signifi- cantly damaged; 2 IS0 8501-2:1994(E) - real savings in costs for the maintenance work should be made possible. NOTE 1 This part of IS0 8501 contains the text in the three official langu
30、ages of ISO, namely English, French and Russian. It also contains the following annexes giving the equivalent text in other languages, published under the responsibility of the respective body indicated: Annex A: Swedish (SIS) Annex B: German (DIN) Annex C: Dutch (“I) Annex D: Italian (UNI) Annex E:
31、 Spanish (AENOR) Annex F: Portuguese (IPQ) Annex G: Arabic (SASO) Annex H: Japanese (JISC) Annex J: Chinese (CSBTS) 3 IS0 8501-2:1994(E) 1 Scope This part of IS0 8501 specifies a series of preparation grades for steel sur- faces after localized removal of previous paint coatings The various prep- ar
32、ation grades are defined by written descriptions (see clause 4) together with the representative photographic examples given in IS0 8501-1. In ad- dition, photographs showing examples of preparation grades P Sa 2% and P Ma are given. This part of IS0 8501 is applicable to surfaces prepared for paint
33、ing by methods such as blast-cleaning, hand- and power-tool cleaning, and machine abrading. This part of IS0 8501 relates the cleanliness of a surface to its visual ap- pearance. In many instances this is sufficient, but for coatings likely to be exposed to severe environments, such as water immersi
34、on and continuous condensation conditions, consideration should be given to testing for soluble salts and other invisible contaminants on the visually clean surface by the physical and chemical methods which form the subjects of the various parts of IS0 8502. The roughness characteristics of the sur
35、face should also be considered by reference to IS0 8503. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of IS0 8501. At the time of publication, the editions indicated were valid. All standards are subject t
36、o revision, and parties to agreements based on this part of IS08501 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. IS0 2409:1992, Paints and var
37、nishes - Cross-cut test. IS0 4624:1978, Paints and varnishes - Pull-off test for adhesion. IS0 4627:1981, Paints and varnishes - Evaluation of the compatibility of a product with a surface to be painted - Methods of test. IS0 4628-1:1982, Paints and varnishes - Evaluation of degradation of paint coa
38、tings - Designation of intensity, quantity and size of common types of defect - Part 1: General principles and rating schemes. 4 IS0 8501-2:1994(E) IS0 4628-2:1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantity and size of common types of def
39、ect - Part 2: Designation of degree of blistering. IS0 4628-3:1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantity and size of common types of defect - Part 3: Designation of degree of rusting. IS0 4628-4: 1982, Paints and varnishes - Evaluati
40、on of degradation of paint coatings - Designation of intensity, quantity and size of common types of defect - Part 4: Designation of degree of cracking. IS0 4628-5:1982, Paints and varnishes - Evaluation of degradation of paint coatings - Designation of intensity, quantity and size of common types o
41、f defect - Part 5: Designation of degree of flaking. IS0 4628-6:1990, Paints and varnishes - Evaluation of degradation of paint coatings - Designation 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 stee
42、l substrates before application of paints and related products - Visual assessment of surface cleanliness - Part 1: Rust grades and preparation grades of uncoated steel substrates and steel substrates after overall removal of previous coatings. 3 Condition of the painted surface to be cleaned The de
43、grees of degradation which may be found on previously coated sur- faces shall be assessed in accordance with IS0 4628, parts 1 to 6. If possible, supplementary information about the previous coating, concern- ing the generic type, number of coats applied, manufacturers name, cor- rosive contaminants
44、, adhesion and film thickness, shall be given. 4 Preparation grades 4.1 General A number of preparation grades, indicating the method of surface prep- aration and the degree of clearling, are specified. The preparation grades are defined (see 4.2, 4.3 and 4.4) by written descriptions of the surface
45、appear- ance after the cleaning operation. 5 IS0 8501-2:1994(E) Each preparation grade is designated by the appropriate letters “Sa“, “St“ or “Ma“ to indicate the type of cleaning method used. The letter P before Sa, St or Ma indicates only localized removal of previous paint coatings. The number fo
46、llowing, if any, indicates the degree of cleaning from mill scale, rust and previous coatings. It should be realized that the various methods of cleaning do not give com- parable results. The degree of cleaning shall be compatible with the generic type of coating system to be used for recoating. Ref
47、erence is made in 4.2 and 4.3 to the photographs in IS0 8501-1 which are representative photographic examples of preparation grades. NOTES 2 The term “foreign matter“ used in 4.2, 4.3 and 4.4 includes water-soluble salts and residues from welding flux. These contaminants cannot be completely removed
48、 from the surface by dry blast-cleaning, hand- or power-tool cleaning or machine abrading; wet blast-cleaning can be used. 3 Mill scale, rust or a paint coating is considered to be poorly adhering if it can be removed by lifting with a blunt putty knife. 4 The photographic representations appended t
49、o this part of IS0 8501 show some typical examples of steel prior to and after localized cleaning. 4.2 Localized blast-cleaning of previously coated surfaces, P Sa Surface preparation by localized blast-cleaning is designated by the letters “P Sa“. Prior to blast-cleaning, any heavy layers of rust shall be removed by chip- ping. Visible oil, grease and dirt shall also be removed. After blast-cleaning, loose dust and debris shall be cleaned from the surface. NOTE 5 For d