彩钢卷产生缺陷的原因

抚顺彩钢卷生产中存在一些缺陷。埋弧焊区域存在气孔、热裂纹、咬边等缺陷。今天，螺旋管制造商将向您展示一些缺陷的原因。

1.咬边。抚顺彩钢卷咬边是沿焊缝边缘焊缝中心线的V型坡口。当焊接速度、电流、电压等条件不合适时，会发生咬边。其中，焊接速度过快比电流不当更容易产生咬边缺陷。
2.气泡。 抚顺彩钢卷焊缝中心经常出现气泡。主要原因是它们仍然以气泡的形式隐藏在焊缝金属中。因此，消除此类缺陷的措施是除去焊丝和焊缝上的铁锈、油污、潮气等物质，然后将焊剂烘干除去水分。此外，它能有效地提高电流，降低焊接速度，减缓液态金属的凝固速度
3.硫磺裂解。 抚顺彩钢卷在焊接强硫偏析区的钢板时，硫偏析区的硫化物进入焊缝金属产生裂纹。这是由于硫偏析区存在低熔点的硫化铁和钢。因此，为了防止这种情况的发生，采用半镇静钢或硫偏析区较少的镇静钢是有效的。其次，对焊缝表面和焊剂进行清洗和干燥。
4.热裂纹。埋弧焊在焊接过程中，会产生热裂纹，尤其是起弧和熄弧坑。为了消除这种裂纹，通常在起弧点和灭弧点安装垫板。在盘管对焊结束后， 抚顺彩钢卷可反焊成叠层焊。当焊接应力较大或焊接金属中硅含量较高时，最容易产生热裂纹。

There are some defects in the production of spiral steel pipe. There are some defects such as air hole, hot crack and undercut in 

submerged arc welding zone. Today, the spiral tube manufacturer will show you some of the reasons for the defects.

1。 Undercut. Undercut is a V-groove along the weld center line of the weld edge. When the welding speed, current, voltage and other conditions are not suitable, undercut will occur. Among them, too fast welding speed is more likely to cause undercut defects than improper current.
2。 Bubbles. Bubbles often appear in the weld center of spiral steel pipe. The main reason is that they are still hidden in the weld metal in the form of bubbles. Therefore, the measures to eliminate such defects are to remove rust, oil, moisture and other substances on the welding wire and weld, and then dry the flux to remove moisture. In addition, it can effectively increase the current, reduce the welding speed and slow down the solidification speed of liquid metal
3。 Sulfur cracking. When the steel plate with strong sulfur segregation zone is welded, the sulfide in the sulfur segregation zone enters the weld metal and produces cracks. This is due to the existence of low melting point iron sulfide and steel in the sulfur segregation zone. Therefore, in order to prevent this, it is effective to use semi killed steel or killed steel with less sulfur segregation zone. Secondly, the weld surface and flux should be cleaned and dried.
4。 Hot cracks. In the process of submerged arc welding, hot cracks will be produced in the weld bead, especially in the arc starting and arc extinguishing pits. In order to eliminate this kind of crack, the backing plate is usually installed at the arc starting point and the arc extinguishing point. At the end of the coil butt welding, the spiral welded pipe can be back welded into stack welding. When the welding stress is large or the silicon content in the welding metal is high, the hot crack is most likely to occur.