Mention the spiral steel pipe had to talk about rebar, and the rebar is hot-rolled ribbed steel commonly known as. It has good strength and toughness, weldability and other characteristics, is widely used in reinforced concrete building structure. Specific to the points, the appearance of rebar ribs are spiral, crescent-shaped and herringbone three, China's current national standard is GB1499.2--2007 provides crescent-shaped. Generally in the international level is to use the level of classification, the British standard is generally 460MPA level, China gb1499.2-2007 standard 335mpa, 400mpa, 500mpa level of steel technical requirements. China's rebar production in 2006 exceeded 80 million t, of which hrb400 steel production has been more than 10 million t, with the continuous development of society, the application of rebar is also constantly expanding.