How to improve the pass rate of Z-directed steel

The lamellar tear-resistant steel is what we call Z-directed steel. It is mainly used as a key material for the complicated parts of the steel plate of some important welded components such as offshore oil production platforms, shipbuilding, boilers and pressure vessels. Z-directed steel is a kind of special smelted and processed steel based on structural steel. The sulfur content of Z-directed steel is one-fifth of that of general steel, and the cross-sectional shrinkage is above 15%.

The stress performance of the steel plate in the thickness direction is called the Z-directed performance. The Z-directed performance of the steel plate can be obtained by the tensile test of the sample, which is generally measured by the shrinkage of the section. In order to ensure the safety performance of Z-directed steel, it must be inspected by ultrasonic before leaving the factory. Only after passing the qualification can the factory send it to the user. Z-directed steel has strict requirements on the purity of molten steel, the quality of casting slabs and the structure of steel plates, and also requires good flaw detection performance. If there is a discrepancy in ultrasonic flaw detection in the production of Z-directed steel, it is possible to strictly control the molten steel by optimizing the smelting process to improve the quality of the molten steel, thereby greatly increasing the qualification rate of Z-directed steel.