carbon precision bright tube for high temperature temper brittleness. Sensitive, containing chromium, manganese, nickel, silicon, two or more alloy steel is very sensitive, the sensitivity of the different types and content of alloy elements and different.聊城据无缝方矩管构造做的无缝方矩管换热器具有构造巩固、适应性强、选材规模广、易于制作、出产成本低一级长处，被广泛用于制冷与空调、化工、医药等职业。