Steel for pressure vessels has strict requirements for chemical composition and quality control, to ensure minimum strength and sufficient toughness, suitable for welding, and if necessary, must meet the special performance requirements of high and low temperatures. The commonly used steel for pressure vessels includes carbon steel and low-alloy steel plates for pressure vessels specified in GB6654, low-alloy steel plates for multi-layer pressure vessels specified in GB6655, steel plates for welded gas cylinders specified in GB6653, low-alloy steel and alloy steel thick steel plates for low-temperature pressure vessels specified in GB3531. In addition, some special equipment (such as chemical, petroleum, aerospace, aviation, ships, etc.) requires high-pressure vessels, and special quality high-strength steel and ultra-high-strength steel are also used.
