压力容器焊缝系数与无损检测比例的拔取(国外英文资料).doc

压力容器焊缝系数与无损检测比例的选取(国外英文资料) Understanding of the ratio of phi to nondestructive testing length TSG R0004-2009: the rules on the proportion of nondestructive testing for welding joints: The non-destructive testing ratio of pressure vessel joints is generally divided into 100% (100%) and local (greater than or equal 20%). The ratio of local non-destructive testing should be greater than or equal to 50% of the carbon steel and low alloy steel cryogenic containers. Complete X-ray detection or ultrasonic testing Comply with one of the following situations A and B class pressure vessel butt joint (A and B class pressure vessel of butt joint division) in accordance with the provisions of GB150, pursuant to the procedures of all NDT method: A, the first Ⅲ design pressure is greater than or equal to 1.6 MPa class pressure vessel; B) the pressure vessel manufactured by the analysis design standard; C, pressure vessel under pressure test or combination pressure test; D. the pressure vessel for the pressure vessel of 1.0 and the pressure vessel that needs to be used but cannot be tested internally. E, standard tensile strength limit is greater than or equal to 540 mpa of low alloy steel pressure vessel, thickness of more than 20 mm, the butt joint should also adopt the with the original NDT methods specified in this standard detection methods in different local detection, the local testing should include all the weld cross area; F, design patterns, and standard requirements for this specification. One, the definition of the welded joint coefficient phi Definition: the welding head coefficient phi is the ratio of the strength of the butt welded joint to the strength of the female. To reflect the welding material, welding factors such as defects and welding residual stress in the welded joint strength is weakened, is a comprehensive reflection of welded joint mechanical properties. Gb150-1998 steel pressure vessel 3.7 rule: the welding joint coefficient phi shall be determined ac