ASTM(SA387GR11CL2) ASME A387GR22CL2 used to manufacture boilers and pressure vessels. The steel plates for pressure vessels can be fabricated into device that will sustain certain pressure, temperature and medium, so they are required to possess high strength, good toughness, weldability and surface quality. Many kinds and sizes of the products are required to deliver in heat treatment condition and satisfy ultrasonic test requirements. These steels are widely used in various sectors in national economy, such as reactor, heat exchanger, separator, spherical tank, oil tank, LPG tank ,boiler steam drum and pressure pipes in machinery, petroleum and chemicals, electric power and metallurgy industries, etc.