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Quality control

Quality Inspection Process

In order to ensure zero-defect production of products, we have established a complete product quality management process and realized process control of color-coated products.

Warehouse acceptance for hot-rolled coils

Confirm whether the order requirements match the raw material grades

Galvanized inspection

Zinc layer weight, zinc layer thickness, adhesion, surface treatment, spangle style(zero or big spangles) etc.

Substrate Inspection

Appearance, strength, material, grade, etc.

Prepainted inspection

Coating thickness, coating surface quality, coating thickness, pencil hardness, impact, etc.

COSASTEEL considers the basic parameters listed below in designing and testing the quality of its products.

Steel Sheet Thickness

COSASTEEL ensures that all of its products adhere strictly to the ordered nominal thickness, and does not exploit the extreme negative tolerance allowed by international standards, since a lower thickness will make a sheet structurally weaker.

Zinc Coating Mass

The service life of zinc-coated steel has a direct linear co-relation to the zinc coating mass, and is the primary parameter in determining the corrosion resistance of galvanized and pre-painted sheet products in outdoor environments. COSASTEEL is committed to meeting a minimum of 90 gsm zinc coating mass on pre-painted steel sheets for use in dry climate conditions.

Paint Thickness

COSASTEEL uses only the highest quality paints from reliable international sources and ensures that paint thickness meets international standards.

Standardized Detection Method

COSASTEEL has two laboratories: one for testing galvanized steel products and another for pre-painted galvanized steel products. Both laboratories have state-of-the-art facilities sourced from renowned agencies from USA and UK to carry out the testing and evaluation of galvanized and pre-painted steel products.

Quality Control 1

Bending Test

Check the adhesion of the coating to the steel substrate after bending
Quality Control 2

Gloss Test

Check whether the surface gloss of the coating meets the standard
Quality Control 3

Stretching Test

Test product tensile strength, yield strength, elongation ect.
Quality Control 4

Color Difference Test

Check whether the coating color meets the product requirements
Quality Control 5

Salt Spray Test

It is suitable for evaluating the corrosion resistance of color-coated panels in neutral salt spray.
Quality Control 6

Hardness Testing

Check the hardness of the substrate to see if it meets the product specification requirements
Quality Control 7

Coating thickness test

Check the paint thickness(Dry Film Thickness) of baking varnish products
Quality Control 8

Product Aging Test

The aging resistance of color-coated panels was tested by simulating the artificial environment climate.
Quality Control 9

Reverse impact and checkered

Evaluate the ability of the coating to resist cracking or falling off when the color-coated plate is subjected to rapid deformation (reverse impact). Check the adhesion between the coating and the substrate
Quality Control 10

Pencil Hardness Test

Check the softness and hardness of the paint film