STUDY ON THE PROCESS OF CTWW CO ₂ GAS SHIELDED WELDING

Abstract

- . , CO2 , , ; CO2 CO2 2.9 , CO2 4 1.7 ; , CO2 , ABSTRACT Cable-type welding wire (CTWW) CO2 gas shielded arc welding, which uses CTWW as consumable electrode, is an innovative arc welding process with high quality, high efficiency and low consumption, thus having significant potential of wide application in industrial manufacturing. So far, however, there is lack of deep study on this new welding technology, hindering its promotion. In this paper, the process mechanism of CTWW CO2 gas shielded arc welding is studied through combining the experimental detection and numerical simulation. By using arc multi-information collection sys- tem, the characteristics of ar cs hape and behavior in CTWW CO2 gas shielded arc welding process is acquired. The photographs of weld without defect are obtained. Based on the test results, the mechanism of CTWW CO2 gas shielded arc welding is explained. A finite element analysis model suitable to CTWW CO2 gas shielded arc welding is developed to simulate the temperature and stress field distribution. The results show that, there exist a unique bunchy electric arc in CTWW CO2 gas shielded arc welding, which is formed through multi-arc rotating and coupling, leading to arc heat concentration; the calculated weld cross section agrees well with the experimental data, validating the accuracy of established heat source model. When the heat input for per unit length in CTWW CO2 gas shielded arc welding is 2.9 times more than that in single welding wire (SWW) CO2 gas shielded arc welding, the weld penetration and width are 4 times and 1.7 times of those in SWW CO2 gas shielded