JIS G3312 Prepainted Steel
JIS G3312 prepainted steel refers to prepainted galvanized steel coils manufactured according to the Japanese standard JIS G3312. This standard is highly recognized in Southeast Asia, the Middle East, Africa, and the Japanese domestic market, and is one of the most frequently specified standards by local builders and appliance manufacturers when making purchases.
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The JIS G3312 prepainted steel coils supplied by Wanzhi Steel feature substrate grades including common grades such as SGCC, CGCC, and SGCH. Zinc coating weights range from Z30 to Z275, and the organic coating systems include PE, SMP, HDP, and PVDF, allowing for flexible combinations based on your project’s environmental requirements and budget.
Available Specifications
| Product Name | JIS G3312 Prepainted Steel |
| Execution Standard | JIS G3312:2024 |
| Thickness | 0.12 – 1.2mm (commonly 0.3 – 0.7mm) |
| Width | 600 – 1250mm |
| Substrate Steel Grade | SGCC, CGCC, SGCH, CGCH, SGCD1, SGC340, SGC400, etc. |
| Zinc Plating Amount | Z30 – Z275 (30–275 g/m² total for both sides) |
| Coil Inner Diameter | 508mm (20 inches) / 610mm (24 inches) |
| Coil Weight | 3 – 8 tons/roll (commonly 3-5 tons) |
| Paint Type | PE / SMP / HDP / PVDF |
| Front Paint Thickness | 15 – 35μm |
| Back Paint Thickness | 5 – 15μm |
| Coating Structure | 2 coats 1 bake (2C1B) or 2 coats 2 bakes (2C2B) |
| Color | RAL color chart/customization |
| Surface Treatment | Smooth, matte, wrinkled, embossed, wood grain, marble, etc. |
| Certification | ISO 9001, ISO 14001, SGS (SGS report for our products) |
| MOQ | 10 TONS |
| Packaging | Standard export packaging (plastic film, moisture-proof paper, and galvanized iron sheet) |
Advantages of JIS G3312 Prepainted Steel
- Manufactured to Standard: JIS G3312 specifies clear numerical requirements for paint film thickness, adhesion, bending performance, and salt spray resistance, making it easy for purchasers to compare quality.
- Wide Range of Substrate Options: The substrates covered by the JIS G3312 standard include SGCC, SGCH, SGC340, SGC400, and others, accommodating various product requirements.
- Suitable for Continuous Processing: Prepainted steel coils can be processed directly through the following steps: uncoiling → slitting → shearing → stamping → bending → roll forming, enabling the production of products such as roof panels, wall panels, door panels, and equipment housings.
- Consistent Surface Color: JIS G 3312 specifies testing requirements for the adhesion, film hardness, and impact resistance of the prepainted coating. The coating exhibits strong adhesion and uniform, consistent color.
JIS G3312 Prepainted Steel Applications
- Pre-painted steel coils are formed into corrugated steel sheets for use as roofing or wall panels in temporary structures, warehouses, fences, carports, and similar applications.
- They are used in the manufacture of housings for home appliances such as refrigerators, outdoor air conditioning units, range hoods, dishwashers, and microwave ovens.
- They are also used in the manufacture of metal equipment housings, metal door panels, interior partitions, decorative wall panels, and other products.
Key Considerations for Purchasing JIS G 3312 Prepainted Steel
Although both JIS G 3312 + Z275 + PVDF and JIS G 3312 + Z100 + PE are referred to as JIS G 3312 Prepainted Steel, their actual performance and suitable applications are entirely different. When purchasing this product, do not simply tell the supplier that you want to buy “JIS G 3312 PPGI.” Be sure to confirm the following details:
- Steel grade: SGCC, SGCH, etc.
- Product type: Coils or flat sheets.
- Intended use: Whether for manufacturing roofing panels or home appliance panels—we can recommend the product best suited to your needs.
- Other specifications: Thickness, width, zinc coating, paint type, paint film thickness, RAL color, surface treatment, coil weight requirements, and packaging requirements.
Only then will the quotes and technical specifications provided by suppliers be comparable. Here is a common example of complete specifications for procurement: JIS G3312 CGCC, coating thickness 20 μm, Z120, 0.45 mm × 1200 mm × C, RAL 5015
Summary
JIS G 3312 prepainted steel is a category of prepainted galvanized steel based on JIS standards, designed to meet the needs of the construction, home appliance, and industrial processing sectors through various combinations of steel grades, zinc coatings, and paint coatings. Its core advantage lies not in any single fixed parameter, but in the ability to tailor the substrate strength, formability, zinc coating, and paint coating system to the specific end use.
We offer not only pre-coated steel coils according to JIS standards, but also those conforming to EN, ASTM, GB, and DIN standards. We strictly adhere to these standards in our production and have rigorous testing procedures. If you have any purchasing needs, please feel free to contact us at any time.
