cryogenic liquid storage tank

The introduction to liquid pressure vessel:

Design pressure vessels with a temperature below -20 ℃; The storage and transportation containers for liquefied ethylene, liquefied natural gas, liquid nitrogen, and liquid hydrogen are all low-temperature pressure vessels. When the temperature of ferritic steel commonly used in pressure vessels drops to a certain temperature, the toughness of the steel will sharply decrease and become brittle. This temperature is commonly referred to as the brittle transition temperature. When pressure vessels are used below the transition temperature, if there are high local stresses caused by defects, residual stresses, stress concentration, and other factors in the vessel, brittle fracture may occur without significant plastic deformation, leading to catastrophic accidents. For low-temperature pressure vessels, suitable materials should be selected first, which should have good toughness at the operating temperature. Low alloy steel treated with refined grain can be used up to -45 ℃, 2.5% nickel steel can be used up to -60 ℃, 3.5% nickel steel can be used up to -104 ℃, and 9% nickel steel can be used up to -196 ℃. Austenitic stainless steel and aluminum alloy can be used below -196 ℃. In order to avoid excessive local stress on low-temperature pressure vessels, excessive stress concentration and additional stress should be avoided when designing the vessel; Strict inspection should be carried out during container manufacturing to prevent dangerous defects from being present in the container. For excessive residual stress caused by welding, residual stress relief treatment should be carried out after welding