1.单面焊双面成形技术的概念(国外英文资料).doc

1.单面焊双面成形技术的概念(国外英文资料) The concept of forming concept of forming technology of single side welding and double side welding of 1. One side welding technology is used in the ordinary electrode and does not need any auxiliary measures under the condition of only root in assembling and positioning welding, should set aside gap according to different operating practices of different welding, welding in the groove of the front, will break in the front and back sides can get uniform, forming good in accordance with the requirements of welding quality. The method is applicable to plate butt joint, butt joints and tubular seat type tube plate joint. Is a boiler, pressure vessel welder should master the skills of [1]. The 2. one side welding common weld defects 2.1 the size of defects Including the weld size error and poor weld shape structure. The appearance of weld and uneven corrugated rough, uneven weld width, too narrow or too wide, the weld height is too low or too high, leg of fillet weld sizes are weld size and shape to meet the requirements. These defects not only make the weld is not beautiful, but also easily lead to stress concentration, influence the bonding strength of the weld seam and base metal. The structure of the 2.2 defects Including porosity, slag, non-metallic inclusions, poor fusion, lack of penetration, undercut, crack, surface defects etc.. These defects are most likely to occur in the welding process. These defects weaken the effective area of the weld, reduce the mechanical properties of welded joints, but also cause the stress concentration caused by crack, leading to structural failure, the welding structure cannot withstand normal working load. The nature of the 2.3 defects Including the mechanical and chemical properties do not meet the requirements of the use of welding defects. Refers to the mechanical properties of tensile strength, yield point elongation, hardness, impact absorbing energy and ductility, fatigue strength, bending angle etc..