Guobiao Standards
Verified mill test certification

GB Standards

Working with Mutual Metal on GB standards documentation.

We supply full material certifications, mill test reports, and dimensional tolerance datasheets compliant with Chinese National Standards (GB/T) for all perforated metal, expanded mesh, and industrial grating fabrications.

GB/T 13304

Steel classification

Material grade cross-referencing and chemical composition verification.

GB/T 700

Carbon structural steel

Tensile specifications and tolerance metrics for industrial grating and plate.

GB/T 13912

Hot-dip galvanizing

Coating thickness, adhesion, and anti-corrosion test reports.

Need EN, ASTM, or ISO equivalence matrices along with your GB paperwork?
View specification tables
Technical Resources

China GB standards alignment

GB (Guobiao) standards are China's national standards for materials, engineering, and construction products. For international contractors and local fabricators sourcing for projects in China, Mutual Metal provides tailored documentation and testing alignment on request.

Project Scope Alignment
Working with your project specifications

Industrial metal products — including welded bar grating, perforated sheets, and expanded metal panels — frequently need documentation structured according to regional project guidelines.

Rather than making blanket claims to specific unverified GB code numbers, our engineering and quality team reviews your submittal package individually. We verify raw material test reports (MTRs), finish certifications, and load calculation sheets against your target criteria.

Material test reports & mill certificates

Provide chemical composition and mechanical property records matched to equivalent GB grade references.

Dimensional & tolerance verification

Inspect bar grating, expanded metal, and perforated patterns against project-specific drawing tolerances.

Custom surface finish compliance

Coordinate galvanizing, powder coating, or anodizing specifications in accordance with project submittal requirements.

Enquiry-based review process

Technical review of your engineer's schedule before production to confirm test protocols and document formats.

How We Align
Submitting GB requirements
1

Share project schedules

Send your bill of materials, required grade equivalents (e.g. Q235B / Q355B or stainless), and drawing sheets.

2

Technical review & verification

Our technical team cross-checks material specifications, hole patterns, bar thickness, and tolerance margins.

3

Documentation package delivery

We supply standard mill certificates, dimensional inspection sheets, and optional third-party testing reports.

Product lines covered

Perforated metal, expanded metal mesh, welded & press-locked bar grating, and custom stair treads fabricated for industrial or architectural applications.

Technical documentation & verification

Need project-specific compliance packages?

Tell our engineering team what standards your project requires. We provide material test reports, dimensional inspection records, and GB compliance data alongside your fabrication quote.

Available documentation items

Material test certificates

Chemical composition, tensile strength, and heat number traceability.

GB compliance records

Verification sheets mapped directly to your national standard criteria.

Dimensional audit logs

Pitch, hole spacing, sheet flatness, and tolerance verification reports.