X射线通过物体时,因被吸收的关系,在底片上产生不同程度的明暗影象。暗黑部分表示X射线易于透过,浅明部分表示X射线难于透过。这些不同程度的明暗区域,有因外形关系(包括内外表面)原来就应该存在的,有的是不应该存在的。从这些不应该出现的阴影上,我们就可以发现问题。最易疏忽的地方就是对比低的地方,或阴影错杂的地方,和焊道外侧。观察底片时,一般使用底片“观察灯”。灯光的强 X-rays pass through the object, because of the absorption of the relationship, in the film to produce varying degrees of light and shade images. The dark part indicates that X-rays are easily transmitted, and the light part indicates that X-rays are difficult to pass through. These different degrees of light and dark areas, due to the appearance of the relationship (including the outer surface) should have existed, and some should not exist. From these shades that should not appear, we can spot the problem. The most neglected place is the low contrast, or the shadow of the wrong place, and weld bead outside. Observed film, the general use of film “observation lamp.” Strong light