During the welding process, welding electrodes and steel plates generate certain slag, which cannot be completely removed. Some of this slag remains in the weld and ultimately forms slag inclusion defects in welding. Slag inclusion is also one of the more common defects in the welding process. Slag inclusion has various classification standards, and the causes of slag inclusion can be explained from different perspectives. During welding, the use of basic welding electrodes can easily produce oxides under high-temperature conditions, especially when influenced by the welding current. Oxides in the welding electrode and oxides in the steel plate rapidly form and enter the welding gap with the molten weld metal. During the cooling process of the metal, slag inclusion defects are prone to form.
To improve the welding quality of spiral steel pipes and effectively address slag inclusion defects, it is necessary to properly handle the groove dimensions. Determine the groove dimensions based on practical experience to effectively avoid the occurrence of slag inclusion defects. Furthermore, attention should be paid to adjusting the welding current and controlling the welding speed, which can ensure uniform heating of the steel plate and avoid oxide residue in cases of excessive cooling or heating. Close attention should also be paid to the swing position of the welding electrode to ensure that its movement trajectory does not deviate significantly, thereby compromising welding quality. Excessive welding slag can also lead to slag inclusion. Therefore, during welding operations, welding slag should be promptly cleaned up. The quality of the welding electrode itself also has a significant impact on slag inclusion defects. If eccentric welding electrodes with uneven distribution of welding material are used, a large amount of slag inclusion will be produced. Therefore, during the selection process of welding electrodes, irregularly shaped electrodes and electrodes with incorrectly positioned cores should be picked out, which can effectively avoid the occurrence of slag inclusion defects.
