Long-side welding platform is the ultimate actuator of micro crystal resonator packaging. The position accuracy of solder joint will directly affect the packaging quality. In order to optimize the ...tolerance grade of the long-side welding platform and reduce the manufacturing cost on the premise of ensuring the position accuracy of the solder joint, the optimal tolerance grade selection scheme of the long-side welding platform for micro crystal resonator packaging is designed. Based on the improved homogeneous coordinate transformation method, the solder joint error model of long-side welding platform is established. Based on the Monte Carlo simulation method, the position error of solder joint is calculated and the tolerance grade selection scheme is proposed. Based on orthogonal experiment method, the noteworthy factors in position error of long-side welding platform is analyzed, the optimal allocation scheme for the tolerance grade of parts is put forward.
An electromagnetic pulse welding (EMPW) system is a complex multifield coupling system. Using finite element software to simulate its processes can better guide the design of the electromagnetic ...pulse welding system and the analysis of the welding mechanism. However, the existing finite element software has a complex model, involves a large amount of calculation, and is time consuming, which is not conducive to the optimization of the welding device. In this paper, an equivalent circuit model based on an improved current wire method is proposed, and the welding process is modeled and analyzed, and then compared with the simulation results of the finite element software COMSOL. The results show that the analytical model is accurate and effective, and it can reduce the calculation time and improve the processing efficiency. Second, based on the equivalent circuit model and taking the maximum impulse of the electromagnetic force as the optimization objective, the shape parameters of the field shaper and the number of turns of the coil in the electromagnetic welding device for plates based on the field shaper are optimized, and the optimal parameters are obtained. Finally, the welding equipment is designed with the optimal parameters, and the electromagnetic welding platform is built. An SS304 stainless steel plate and A1060 aluminum plate with a thickness of 1 mm are welded, and the dissimilar metal plates are well connected.
Because welding repair of nuclear power plant at the underwater environment, in order to simplify the sealing and increase the safety of test equipment, hydraulic drive automatic welding platform was ...designed that provides the relative motion required during underwater welding; Through PLC control electro-hydraulic servo valve to control welding slider's movement. Oscillating center sensor realized the track of oscillating center. Movement of welding was controlled through the manual control box. The whole system stable and reliable and can meet the needs of underwater welding.
The magnetic pulse spot welding studied in this paper can achieve the connection of sheet metal with the aid of a field shaper. The magnetic field shaper which is placed between the metal components ...and an electromagnetic coil has the function of concentrating the magnetic field, enhancing the electromagnetic force around the weld zone, meanwhile, it can protect the electromagnetic coil. This paper carried out a numerical simulation of the principle of the field shaper for magnetic pulse welding of sheet metal by means of the FEA software COMSOL. The electromagnetic and structural parameters of the high-strength coil and field shaper have been designed, and an electromagnetic welding platform is built, the welding experiments of 304 stainless steel sheet and 1060 aluminum sheet both with a thickness of 1 mm are carried out. The experimental results show that the method can achieve the connection of sheet metal very well.
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