The clauses in the following documents become the clauses of this standard through the reference of this standard. For dated references, all subsequent amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement based on this standard to study whether new versions of these documents can be used Version. For undated reference documents, the new version applies to this standard.
CB/T 231 Ship coating technical requirements
CB 3381 Safety regulations for ship painting operations
CB/T 3513 Technical Requirements for Ship Derusting Coating Quality Acceptance
CB/T 3718 Ship coating film thickness testing requirements
CB/Z235 Ship coating design technical requirements
ISO 4628-1:1982 Assessment of paint film deterioration of paints and varnishes - Assessment of degree, amount and size of general types of damage - Part 1: General principles and scales
ISO 4628-2:1982 Assessment of paint film aging of paints and varnishes - Assessment of degree, quantity and size of general types of damage No. ? Part: Evaluation of blistering grade
ISO 4628 — 3:1982 Evaluation of paint film deterioration of paints and varnishes; Evaluation of degree, amount and size of general types of damage; Part 3: Evaluation of degrees of rusting
ISO 4628-4 : 1982 Evaluation of paint film deterioration of paints and varnishes; Evaluation of degree, amount and size of general types of damage; Part 4: Evaluation of degrees of cracking
ISO 4628 — 5:1982 Assessment of paint film deterioration of paints and varnishes - Assessment of degree, amount and size of general types of damage - Part 5: Assessment of degrees of peeling
ASTM D610-01:1989 Standard Test Method for Rating Corrosion of Painted Steel Surfaces
Terms and Definitions
The following terms and definitions apply to this standard.
3.1 surface pretreatment surface preparatiOn
Before construction, the steel plate or profile is mechanically or chemically removed from foreign matter such as scale and rust, and then coated with shop primer.
Note: rewrite the definition of GB/T 12466-1990dP4.1.
3.2 secondary surface preparation
For the surface coated with shop primer (or other coatings), the surface treatment process is carried out again on the aging, damaged and rusted parts of the primer (or coating) caused by thermal influence or mechanical reasons.
Note: Rewrite the definition in 4.2 of GB/T 12466-1990.
3.3 rust rusting
A phenomenon in which a red or yellow iron oxide layer is produced locally or as a whole on the steel surface under the coating. It is often accompanied by defects such as blistering, cracking, and peeling of the coating.
3.4 peeling peeling
The separation of one or more coats from the underlying coating, or the complete separation of a coating from a substrate.
3.5 Blistering
The coating is detached from the substrate or undercoat due to local loss of adhesion, making the coating appear like a circular convex deformation. The interior of the protrusion may contain liquid, vapor, other gases or crystals.
3.6 Cracking
The phenomenon of discontinuous surface crack changes in the coating. Usually caused by aging coating. The more important forms are: microcracks, fine cracks, small cracks, deep cracks, chapped cracks, and crow's claw cracks.
3.7 Marine biological fouling
The underwater part of the hull or steel structure, due to the adhesion of marine organisms, causes surface damage.
Ship coating quality control
4.1 Painting design
Ship coating design should be carried out in accordance with the provisions of CB/Z235, and the "Painting Instructions" should be compiled.
4.2 Coating construction
4.2.1 The surface quality after shot blasting or shot peening should meet the requirements of CB/T 3513.
4.2.2 During the second derusting operation, the environmental humidity control, process requirements and quality should meet the requirements of N/T231.
4.2.3 The coating operation environment and construction technology shall meet the requirements of CB 3381 and CB/T 231.
4.2.4 The appearance quality of the coating should meet the requirements of CB/T 3513.
4.2.5 The film thickness distribution of the coating shall comply with the requirements of CB/T 3718 unless otherwise specified in the ship construction instructions.
4.3 Quality inspection
4.3.1 The scope of coating quality inspection is: steel pretreatment, secondary rust removal and surface cleaning, coating appearance quality and coating film thickness.
4.3.2 The coating quality inspection items and inspection requirements shall be in accordance with the provisions of CB/T 3513.
Classification of coating quality defects
5.1 General
5.1.1 There are five types of coating quality defects: rust, peeling, blistering, cracking, and marine biofouling, which are represented by R, P, B, C, and F codes.
5.1.2 Each coating quality defect is divided into 6 grades, represented by numbers 0 to 5. "0" indicates no defects; "5" indicates defects so severe that no further classification is necessary. The grades represented by the four numbers 1, 2, 3, and 4 cover the range from no flaws to the most serious flaws, with the severity of the flaws increasing as the numbers increase.
5.2 Classification of coating corrosion
The level of corrosion defects of the coating is determined according to Table 1.
5.3 Grading of coating peeling
The level of coating peeling defects is determined according to Table 2.
The following types of coating peeling shall be stated in the test report:
a) peeling of the topcoat from the underlying coating;
b) The entire coating system peels off from the substrate.
5.4 Grading of coating blisters
The grade of blistering defect of the coating is determined according to Table 3. In case of dispute, follow the provisions of 5.7.
Whether the blistering of the coating occurs on the surface or from the substrate should be stated in the test report.
5.5 Classification of coating cracking
The coating cracking grade is determined according to Table 4. In case of dispute, follow the provisions of 5.7.
The following types of coating cracking shall be stated in the test report:
a) The surface of the coating system is cracked and the topcoat does not penetrate completely:
b ) Cracking penetrates completely through the topcoat, but other coatings underneath are unaffected:
c) Cracks penetrate the entire coating system.
5.6 Classification of coated marine biofouling
The marine biofouling grade of the coating is determined according to Table 5.
5.7 Correspondence between coating quality defect classification and ISO and ASTM standards
Refer to Appendix A for the corresponding relationship between the classification of coating quality defects in this standard and the classification of coating quality defects in ISO 4628:1982 and ASTU D61001:1989. When there is a dispute, the photos of defect classification and assessment in ISO 4628:1982 and ASTM D610-01:1989 shall be used as the arbitration basis.
Coating Quality Assurance
6.1 The coating quality inspection report shall at least include the following contents:
a) The type and location of the tested product and information related to the coating system:
b) testing standards;
c) type of defect;
d) Defect class;
e) If necessary, additional text descriptions can be added, such as "bubbles exist in the top coat and stop at the middle coat", "the number of layers and the average size of the bubbles", "the number of layers where peeling occurs, and the depth of peeling and average size" etc.;
f) Date of inspection.
