When selecting materials for pressure vessels, it is necessary to comprehensively consider various performance requirements to ensure the safe and reliable operation of pressure vessels under various working conditions.

First of all, strength is one of the key performance requirements. For pressure vessels that withstand high pressure, such as high-pressure reactors in the petrochemical industry, it is necessary to select materials with high strength. Like alloy steel, it has high yield strength and tensile strength and can withstand huge pressure without plastic deformation or rupture. When calculating the required strength, the appropriate material strength grade should be determined according to the relevant standard formula based on the design pressure, diameter, wall thickness and other parameters of the container.

Secondly, corrosion resistance cannot be ignored. If pressure vessels are used to contain corrosive media, such as acid and alkali solutions in chemical industry, the corrosion resistance of the material is crucial. Stainless steel is a commonly used corrosion-resistant material, such as 316L stainless steel, which contains molybdenum, so that it can still maintain good corrosion resistance in corrosive environments such as chloride ions. For some special highly corrosive media, titanium or nickel-based alloys may need to be selected. Although they are more expensive, they can ensure the long-term stable operation of the container.

In addition, consider temperature performance. In high-temperature environments, such as high-temperature reaction vessels in refineries, the high-temperature strength and oxidation resistance of materials are the focus. Chromium-molybdenum alloy steel has good strength retention and oxidation resistance at high temperatures. In low-temperature environments, such as storage containers for liquefied natural gas, materials need to have good low-temperature toughness to prevent brittle fracture at low temperatures. Austenitic stainless steel can also maintain good toughness at low temperatures.

In addition, the machinability and weldability of the material need to be considered. Good machinability facilitates the manufacturing and forming of containers, and good weldability can ensure welding quality and reduce welding defects. For example, some low-carbon steels have good weldability and are easy to manufacture pressure vessels of various shapes.

According to the specific performance requirements of pressure vessels, comprehensive evaluation of strength, corrosion resistance, temperature performance, machinability and weldability and other factors can accurately select the appropriate material.