1、 Common welding defects can be divided into four categories:

（1）焊缝尺寸不符合要求：如焊缝过高、过宽、过窄、高低差过大、焊缝过渡到母材不圆滑等。

(1) The weld size does not meet the requirements: for example, the weld is too high, too wide, too narrow, the height difference is too large, and the weld transition to the base metal is not smooth.

（2）焊接表面缺陷：如咬边、焊瘤、内凹、满溢、未焊透、表面气孔、表面裂纹等。

(2) Welding surface defects: such as undercut, overlap, concave, overflow, incomplete penetration, surface porosity, surface crack, etc.

（3）焊缝内部缺陷：如气孔、夹渣、裂纹、未熔合、夹钨、双面焊的未焊透等。

(3) Internal defects of weld: such as air hole, slag inclusion, crack, incomplete fusion, tungsten inclusion, incomplete penetration of double-sided welding, etc.

（4）焊接接头性能不符合要求：因过热、过烧等原因导致焊接接头的机械性能、抗腐蚀性能降低等。  `

(4) The performance of the welded joint does not meet the requirements: the mechanical properties and corrosion resistance of the welded joint are reduced due to overheating, overburning and other reasons`

二、 焊接缺陷

2、 Welding defects

（一）焊接变形

（1） Welding deformation

工件焊后一般都会产生变形，如果变形量超过允许值，就会影响使用。

Generally, the workpiece will be deformed after welding. If the deformation exceeds the allowable value, it will affect the use.

产生的主要原因是焊件不均匀地局部加热和冷却。因为焊接时，焊件仅在局部区域被加热到高温，离焊缝愈近，温度愈高，膨胀也愈大。

The main reason is uneven local heating and cooling of weldments. During welding, the weldment is heated to high temperature only in local areas. The closer it is to the weld, the higher the temperature and the greater the expansion.

但是，加热区域的金属因受到周围温度较低的金属阻止，却不能自由膨胀；而冷却时又由于周围金属的牵制不能自由地收缩。

However, the metal in the heating area can not expand freely due to the metal with lower ambient temperature; When cooling, it can not shrink freely due to the restriction of surrounding metal.

结果这部分加热的金属存在拉应力，而其它部分的金属则存在与之平衡的压应力。

As a result, the metal heated in this part has tensile stress, while the metal in other parts has compressive stress in equilibrium with it.

当这些应力超过金属的屈服极限时，将产生焊接变形；当超过金属的强度极限时，则会出现裂缝。

When these stresses exceed the yield limit of metal, welding deformation will occur; When the strength limit of metal is exceeded, cracks will appear.

（二）焊缝的外部缺陷

（2） External defects of welds

1.焊缝增强过高

1. weld reinforcement is too high

当焊接坡口的角度开得太小或焊接电流过小时，均会出现这种现象。因此，为提高压力容器的疲劳寿命，要求将焊缝的增强高铲平。

This phenomenon occurs when the angle of the welding groove is too small or the welding current is too small. Therefore, in order to improve the fatigue life of pressure vessels, it is required to flatten the weld reinforcement.

2.焊缝过凹

2. the weld is too concave

因焊缝工作截面的减小而使接头处的强度降低。

The strength of the joint is reduced due to the reduction of the working section of the weld.

3.焊缝咬边

3. weld undercut

在工件上沿焊缝边缘所形成的凹陷叫咬边。它不仅减少了接头工作截面，而且在咬边处造成严重的应力集中。

The depression formed along the weld edge on the workpiece is called undercut. It not only reduces the working section of the joint, but also causes serious stress concentration at the undercut.

4.焊瘤

4. weld beading

熔化金属流到溶池边缘未溶化的工件上，堆积形成焊瘤，它与工件没有熔合。焊瘤对静载强度无影响，但会引起应力集中，使动载强度降低。

The molten metal flows to the unmelted workpiece at the edge of the molten pool and accumulates to form a weld bead, which is not fused with the workpiece. The weld bead has no effect on the static load strength, but it will cause stress concentration and reduce the dynamic load strength.

5.烧穿

5. burn through

烧穿是指部分熔化金属从焊缝反面漏出，甚烧穿成洞，它使接头强度下降。

Burn through refers to the leakage of some molten metal from the reverse side of the weld, or even burn through into holes, which reduces the strength of the joint.

以上五种缺陷存在于焊缝的外表，肉眼就能发现，并可及时补焊。

The above five defects exist in the appearance of the weld, which can be found by naked eyes and can be repaired in time.

以上就是为大家介绍的山东数控焊接设备http://www.tayfsk.com有关的详细的介绍,希望对您有所帮助.如果您有什么疑问的话,欢迎联系我们.我们将以的态度,为您提供服务.

The above is the Shandong CNC welding equipment introduced to you http://www.tayfsk.com I hope that the detailed introduction to the will be helpful to you If you have any questions, please contact us We will provide you with professional service