GB/T 6747-2008Shop primer for ship building (English PDF)

3.1 Type

Shop primers are available in two types. those containing zinc powder and those without. Type I. Contains zinc powder; Type II. Does not contain zinc powder.

3.2 Grade (Type I only)

Grade I-12.after 12 months of exposure in a marine climate environment, rust <= grade 1;

Grade I-6.after 6 months of exposure in a marine climate environment, rust <= grade 1;

Grade I-3.after 3 months of exposure in a marine climate environment, rust <= grade 1.

4.1 General requirements

4.1.1 The performance of the shop primer shall meet the requirements of Table 1.

4.1.2 To meet the needs of automated production line operations, the shop primer shall be able to dry in a relatively short time.

4.1.3 The shop primer shall be widely compatible with the next coat of paint and have good recoating properties for old shop primer films that have been exposed for a long time.

4.1.4 Occupational safety during primer coating in the workshop shall comply with the relevant provisions of CB 3881.

4.1.5 The reduction in cutting speed shall not exceed 15%.

4.2 Technical requirements

The product shall meet the technical specifications in Table 1.

5.1 Test environment

Proceed in accordance with GB/T 9278.

5.2 Test plate preparation

5.2.1 Material and surface treatment of test plates

Unless otherwise specified, all test plates shall be made of ordinary carbon structural steel plates as specified in GB/T 9271. The surface treatment of the test plates shall meet Grade specified in GB/T 8923-1988.

5.2.2 Preparation of test samples

Unless otherwise specified, apply by brush or spray according to GB/T 1727. The dry film thickness shall meet the requirements of Table 1. Unless otherwise specified, test samples shall be placed under test environmental conditions for 7 days before testing.

5.3 Drying time

The determination of surface drying time shall be carried out according to Method B of GB/T 1728-1979.

5.4 Adhesion

Proceed according to GB/T 1720.

5.5 Coating thickness

5.5.1 Proceed according to GB/T 13452.2

5.5.2 The thickness of the paint film applied to the steel plate in the production line shall be determined in accordance with A.1 in Annex A.

5.6 Zinc content in non-volatile matter

Proceed according to section 5.13 of HG/T 3668-2000.

5.7 Weather resistance

5.7.2 The test results shall be evaluated in accordance with 4.6 of GB/T 1766-2008.

5.7.1 Conduct the test according to GB/T 9276

5.8 Welding and cutting

Proceed as described in A.2 of Annex A.

6.1 Inspection responsibility

Unless otherwise specified in the contract or order, the manufacturer of the shop primer shall be responsible for all inspections specified in this Standard. If necessary, the ordering party has the right to inspect any item as described in this Standard.

6.2 Classification of inspections

6.2.1 The inspection of shop primer for ship building is divided into type inspection and exit-factory inspection.

6.2.2 Type inspection is periodic inspection. Exit-factory inspection is batch-by-batch inspection.

6.3 Sampling

Unless otherwise specified, shop primer for ship building shall be sampled in accordance with GB/T 3186. Two samples shall be prepared. one sealed and stored for future reference, and the other used as a test sample.

6.4 Type inspection

6.4.1 Inspection conditions

Type inspection of shop primers shall be conducted under any of the following circumstances.

a) During normal production, a type inspection shall be conducted every four years;

b) When a new product is put into production;

c) When changes in materials or processes are sufficient to affect product performance;

6.4.2 Inspection items

The shop primer shall be type inspected according to the items specified in Table 2.

6.5 Exit-factory inspection

6.5.1 Inspection conditions

Each batch of paint shall undergo exit-factory inspection before leaving the factory.

6.5.2 Batch

Exit-factory inspection is conducted on a batch basis, with each paint storage tank constituting one batch.

6.5.3 Inspection items

The shop primer shall be subjected to exit-factory inspection according to the items specified in Table 2.

6.6 Qualification criteria

If, during the inspection of paint products, the ordering party finds that the product quality does not meet the technical requirements of this Standard, both the supplier and the buyer shall re-test with double the quantity as specified in GB/T 3186. If the product still does not meet the technical requirements of this Standard, it is considered a non-conforming product.

7.1 Marks

The marks on shop primer products shall comply with the requirements of GB/T 9750.

7.2 Packaging

The packaging of shop primer products shall comply with the requirements of GB 190,

GB/T 191 and GB/T 13491.

7.3 Transportation

Shop primer products shall meet the requirements of HG/T 2458 during transportation to prevent rain and direct sunlight exposure.

7.4 Storage

Shop primer products shall meet the requirements of HG/T 2458. They shall be stored in a well-ventilated, dry warehouse, protected from direct sunlight and fire sources.

Under the condition of being sealed in its original packaging, the product has a shelf life of 6 months from the date of production (or according to the product's technical requirements). Products exceeding the shelf life can be inspected according to the factory inspection items specified in this Standard; if the inspection is qualified, it can still be used. […]