Research on Wide-Strip Submerged Arc and Electroslag Overlay Welding

Literature Overview

Published in 2010 in the journal Electric Welding Machine, this paper by Li Pengfei and Wang Jiantao from Xi'an Nuclear Equipment Co., Ltd. investigates wide-strip electroslag and submerged arc overlay welding techniques for improving the efficiency and quality of corrosion-resistant overlay welding. The authors used domestically produced welding strips and fluxes with Swedish ESAB welding equipment, and conducted tests including intergranular corrosion, side bend, metallographic examination, and hardness measurement. The study demonstrates that both processes can produce overlay metal with properties comparable to 304L stainless steel, and that magnetic control devices can improve weld bead quality during strip electrode submerged arc welding.

Core Technical Points

The drive to improve overlay welding efficiency for corrosion-resistant applications is well justified in industries such as nuclear power, where large-diameter vessels and components require extensive cladding. Wide-strip processes offer the potential for significantly higher deposition rates compared to conventional wire electrode processes. The authors investigated both electroslag and submerged arc variants of wide-strip overlay welding, using domestically sourced consumables to reduce dependency on imported materials.

Key Technical Parameters

Intergranular Corrosion and Mechanical Properties

The intergranular corrosion (IGC) test is a critical evaluation for austenitic stainless steel overlay deposits, as sensitization due to chromium carbide precipitation at grain boundaries can severely compromise corrosion resistance. The authors confirmed that the overlay deposits from both processes exhibited acceptable IGC resistance, indicating that the welding heat input and cooling rates were controlled to minimize sensitization. The side bend test evaluated the ductility and soundness of the deposit, while metallographic examination revealed the microstructure and any potential defects.

Magnetic Control Device Application

The use of magnetic control devices during wide-strip submerged arc welding is a notable process innovation. Magnetic fields can be applied to the weld pool to influence arc stability, bead geometry, and solidification characteristics. The authors demonstrated that magnetic control improves weld bead quality, which is particularly beneficial for achieving consistent cladding coverage and reducing surface defects. This represents a practical approach to enhancing the reliability of wide-strip submerged arc overlay welding.

Engineering Practice Integration

For nuclear equipment manufacturers, the ability to use domestic consumables with proven foreign welding equipment represents a practical compromise between cost and quality. The validation that both EES and EAS processes can produce 304L-equivalent deposits provides flexibility in process selection based on production requirements and equipment availability. The magnetic control device finding offers a pathway for further improving the consistency of submerged arc overlay welding, which could be particularly valuable for large-scale cladding operations.

Study Insights and Implications

This research contributes to the body of knowledge on wide-strip overlay welding by demonstrating the viability of domestic consumables and the potential of magnetic control technology. The comprehensive testing protocol, including intergranular corrosion evaluation, provides assurance that the deposits meet the stringent requirements of nuclear applications. For engineers involved in pressure vessel and component manufacturing, this work highlights the importance of consumable qualification and process optimization in achieving reliable overlay performance. The integration of magnetic control technology represents an area of further investigation that could yield additional improvements in overlay welding quality and productivity.