The international welding quality system ISO 3834 provides comprehensive management measures and plans for the implementation of enterprise' welding quality. The system's specified quality grades from high to low, mainly include the following: ISO 3834-2: Comprehensive quality requirements; ISO 3834-3: Standard quality requirements; ISO 3834-4: Elementary quality requirements. When a manufacturer meets a specific quality level, it can also satisfy all lower quality level requirements without further verification. Like ISO9000, ISO3834 is not a compulsory certification, but if a manufacturing strictly controls the quality of welding according to ISO 3834, the quality of its products can be guaranteed; gaining the certification of ISO3834 can also make the manufacturing more competitive in the international market, and more easily to obtain high quality overseas orders.