ISO 8504-3:2018 pdf free download.Preparation of steel substrates before application of paints and related products — Surface preparation methods — Part 3: Hand- and power tool cleaning.
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 of rust and mill scale;
b) the presence of surface contaminants, including salts. dust, oils and greases:
c) the surface profile.
ISO 8501 and 150 8502 have been prepared to provide methods of assessing these factors, while ISO 8504 provides guidance on the preparation methods that are available for cleaning steel substrates, indicating the capabilities of each In attaining specified levels ofcleanliness,
ISO 8504-3 do not contain recommendations for the protective coating systems to be applied to the steel surface. Neither do they contain 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 and codes of practice. The users of ISO 8504-3 should ensure that the qualities specified are:
— compatible with and appropriate both for the environmental conditions to which the steel will be exposed and for the protective coating system to be used;
— within the capability of the cleaning procedure specified.
The three International Standards referred to above deal with the following aspects of preparation of steel substrates:
— ISO 8501 (all parts): visual assessment of surface cleanliness;
— ISO 8502 (all parts): tests for the assessment of surface cleanliness;
— ISO 8504 (all parts): surface preparation methods,
Each of ISO 8504-3 Is in turn divided Into separate parts.
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 steel. It also assists in reducing the amounts of contaminants that initiate corrosion.
ISO 8504-3 describes methods for hand- and power-tool cleaning. It should be read in conunction with ISO 8504-1.
Hand- and power-tool cleaning are methods of surface preparation that generally provide a surface cleanliness which is inferior to that achieved by abrasive blast-cleaning. When a result similar to that of abrasive blast-cleaning is required, these methods need in most cases the use of more than one type of power tool, which makes surface preparation complicated and expensive. It is usually not possible to remove oil, grease and corrosion-stimulating substances such as chlorides and sulphates.
Power-tool cleaning will generally provide a better foundation for the priming paint than hand-tool cleaning, which results in better paint performance.
Hand- and power-tocil cleaning are both suitable methods of surface preparation. Hand-tool cleaning particularly requires the use of priming paints having good surface wetting ability. Power-tool cleaning is appropriate when a higher-quality surface preparation grade is required and when blast-cleaning is not permitted or the interested parties decide that it is not feasible.
Representative photographic examples of St 2, St 3, PSt 2, PSt 3 and PMa are available (see ISO 8501-1 and ISO 8501-2) for assessing some new and previously coated steel surfaces cleaned using hand or
1 Scope
ISO 8504-3 describes methods for hand-tool and power-tool cleaning of steel substrates before application of paints and related products. It is applicable both to new steelwork and to steel surfaces that have been coated previously and that show areas of breakdown requiring maintenance painting. It describes the equipment to be used and the procedures to be followed.
2 NormatIve references
The following documents are referred to In the text in such a way that some or all of their content constitutes requirements of ISO 8504-3. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 8501-1. Preparation of steel substrates before application of points and related products — Visual assessment of surface cleanliness — Part I: Rust grades and preparation grades of uncoated steel substrates and cf steel substrates after overall removal of previous coat,ngs
ISO 8501’2. Preparation of steel substrates before application of paints and related products — Visual assessment of surface cleanliness — Port 2: Preparation grades of previously coated steel substrates after locahzed removal of previous coatings
3 Terms and definitions
For the purposes of ISO 8504-3, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
4.4.3 Use power-wire brushing, power ahr.idlng. power impact or power-assisted rotary tools to remove loose mill scale, loose or non-adherent rust and loose paint to the specified or agreed preparation grade.
4.4.4 Use rotary impact tools to provide a surface profile.
4.5 Final preparation before painting
Remove any burrs, sharp ridges or sharp cuts that have been produced during the cleaning operation (see ISO 8501.3).
Immediately before painting, unless otherwise specified, ensure that any remaining sound paint has no residual gloss. Ensure that the edges olany remaining intact paint have been feathered (bevelled) using one of the methods given in 43 or 4.4.
Dry the surface, Ilnecessary. and remove any residual loose matter resulting from the cleaning methods by brushing, vacuum cleaning or a blast of clean, dry compressed air.
5 Reference standards
Unless otherwise agreed, visual reference standards shall be used to supplement the cleaning criteria given in C1aus 4. These reference standards shall be either samples or photographs provided by one of the parties or published reference standards as given in ISO 8501-1 or ISO 8501-2 (see also Introduction, last paragraph).
6 Assessment
Work performed under this standard Is subject to assessment by a representative of those responsible for establishing the requirements. Work areas shall be accessible to the assessor. The procedures and times of assessment shall be as agreed upon by those responsible for establishing the requirements and those responsible for performing the work.
Assess alt cleaned surfaces in accordance with ISO 8501-1 and ISO 8501-2 for conformity. In the event of non-conformity repeat the procedure (see CIausL4)-
Representative photographic examples of steel substrates after hand- or power-tool deaning are provided In ISO 8501-1.