4 obvious signs of the quality of packaging steel strips

4 obvious signs of the quality of packaging steel strips:
　　1. For the surface color and appearance quality of the packaging steel strip, place the monitored part of the packaging steel strip on the platform, and use a one-meter ruler against the concave side of the packaging steel strip to measure the meter ruler The maximum distance to the concave side.
　　2. The coating film thickness and galvanized thickness of the packaging steel strip are measured with response precision measuring instruments. The measuring position should be no less than 3 mm away from the edge of the packaging steel strip, the interval should be roughly equal, and the length should be no less than 100 mm. Three points are measured on each side. The arithmetic average of the six test values u200bu200bis the thickness of the coating film or the thickness of the galvanized layer.
　　3. The test items, sampling quantity, sampling method and test method of each batch of packaging steel strip shall conform to the national regulations.
　　4. The sample for tensile test should conform to the requirements of GB/T6397, and the sample adopts a full rectangular section shape without machining. The original cross-sectional area is calculated according to the measured size.