GB/T 30789.7-2015Paints and varnishes -- Evaluation of degradation of coatings -- Designation of quantity and size of defects, and of intensity of uniform changes in appearance -- Part 7: Assessment of degree of chalking by velvet method (English PDF)

Foreword

GB/T 30789 "Paints and varnish coating aging rating number and size of the defect and the identity of the extent of uniform changes in appearance." Divided into nine sections.

--- Part 1. General and identification systems;

--- Part 2. Evaluation of blistering levels;

--- Part 3. Evaluation of rust grade;

--- Part 4. Evaluation cracking grade;

--- Part 5. Evaluation of flaking grade;

--- Part 6. Assessment of degree of chalking tape method;

--- Part 7. Method for Evaluation of velvet cloth chalking rating;

--- Part 8. scribe or other artificial defect assessment and corrosion peeling peripheral level;

--- Part 9. Evaluation of filiform corrosion level.

This section GB/T Part of 730,789.

This section drafted in accordance with GB/T 1.1-2009 given rules.

This section uses the translation method identical with ISO 4628-7:2003 "number and size of paints and varnishes Evaluation of degradation of coatings defects as well as the appearance of a uniform degree of change identification - Part 7. Method for Evaluation of velvet cloth chalking grade. " Consistency correspondence between this part of international documents and normative references of our files are as follows.

GB/T 13288.1 steel surface roughness characteristics - Part 1 before application of paints and spray steel surface treatment after cleaning. for Evaluation of technical requirements and definitions after blast - cleaned steel surface roughness of the surface roughness comparison specimens ISO 's (ISO 8503-1. 1988, IDT).

This part is proposed by the China Petroleum and Chemical Industry Association.

This part of the National Standardization Technical Committee and the pigment coating (SAC/TC5) centralized.

This section drafted by. CNOOC Changzhou Paint Chemical Research Institute Co., Ltd., Guangzhou Institute of Materials Co., Ltd., Nanjing production Product Quality Supervision and Inspection Institute, Shenzhen Hirota Decoration Group Co., Ltd., Guangzhou standard Geda laboratory equipment supplies Limited.

1 Scope

This section GB/T 30789 requirements, a chalking grade evaluation method, especially for white on a rough surface or other color Lacquer coating and multi-coating system (for example, paragraph 4 of roughness greater than the roughness comparison specimens G ISO 8503-1 defined in) degree of chalking assessment.

The method specified in this standard can also be used to assess coating and multi-coating system of degree of chalking on the smooth surface, but the provisions of ISO 4628-6 the method is more suitable.

This test method is applicable to the mineral substrate coating and multi-coating system, such as. fiber cement boards, bricks, concrete and mortar bottom, measuring Test is not affected by the surface structure. Experienced operators using this method is very effective and can be used for laboratory and field evaluation.

Note 1. When the technical specifications stated with reference to this section, the test conditions (including aging method and substrate) agreed by all relevant parties.

Note 2. This section provides a relative level evaluation method, therefore, does not apply to the agreement. Table 1 Note.

ISO 4628-1 defines coatings for aging defect number and size of uniform changes in appearance as well as the degree of identification, assessment and overview of the General System. The assessment system is particularly suitable for general types of defects and damage caused by aging, such as color changes, such as yellowing.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version suitable for use herein Member. For undated references, the latest edition (including any amendments) applies to this document.

The number and size of the ISO 4628-1 Paints and varnishes - Evaluation of degradation of coatings defects and uniformity of appearance change logo Part 1. General and identification system (Paintsandvarnishes-Evaluationofdegradationofcoatings-Designation ofquantityandsizeofdefects, andofintensityofuniformchangesinappearance-Part 1. Generalin-troductionanddesignationsystem) ISO 4628-6. the number and size of uniform changes in appearance as well as the extent of 1990 Paints and varnishes - Evaluation of degradation of coatings defects Logo Part 6. Assessment of degree of chalking tape method (Paintsandvarnishes-Evaluationofdegradationofpaintcoat-ings-Designationofintensity, quantityandsizeofcommontypesofdefect-Part 6. Ratingofdegree ofchalkingbytapemethod) Steel surface roughness characteristics ISO 8503-1 application of paints and related products - steel surfaces clean up after the blast Part 1. Technical requirements for the assessment after abrasive blast cleaned steel surface roughness of ISO surface profile comparators and definitions (Preparationofsteelsubstratesbeforeapplicationofpaintsandrelatedproducts-Surfaceroughness characteristicsofblast-cleanedsteelsubstrates-Part 1. SpecificationsanddefinitionsforISO surface profilecomparatorsfortheassessmentofabrasiveblast-cleanedsurfaces)

3 Terms and Definitions

The following terms and definitions apply to this document.