Study of Pneumatic Force Servo System for Resistance Spot Welding

The purpose of this paper is to develop a pneumatic servo drive mechanism, which is the basis of high performance pneumatic servo gun for resistance spot welding. In order to increase the output force and reduce costs, booster cylinder and high speed solenoid valve are included in the system. In this paper, a mathematical model of the pneumatic force servo system is derived. Pulse-Width-Modulation control scheme is given to control the solenoid valves. Computer simulation results and experimental results show that the designed pneumatic servo force system has a good performance, which verifies the feasibility of the designed scheme.

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Evaluation of heat transfer within numerical models of resistance spot welding using high-speed thermography

Journal of Materials Processing Technology ◽

10.1016/j.jmatprotec.2021.117276 ◽

2021 ◽

pp. 117276

Author(s):

Eric Brizes ◽

Joseph Jaskowiak ◽

Tim Abke ◽

Hassan Ghassemi-Armaki ◽

Antonio Ramirez

Keyword(s):

Heat Transfer ◽

Resistance Spot Welding ◽

Spot Welding ◽

High Speed ◽

Numerical Models ◽

Resistance Spot

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Control-Oriented Modeling and Simulation of a Low Carbon Steel A.C. Resistance Spot Welding Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.1456 ◽

2012 ◽

Vol 538-541 ◽

pp. 1456-1459

Author(s):

Yan Xi ◽

Liang Gong ◽

Cheng Liang Liu

Keyword(s):

Resistance Spot Welding ◽

Spot Welding ◽

High Performance ◽

Physical Phenomenon ◽

Low Carbon Steel ◽

Welding Process ◽

Thermal Response ◽

Low Carbon ◽

Thermal Dynamics ◽

Resistance Spot

Resistance spot welding (RSW) has been extensively used as a sheet metal joining process, and the welding process identification is the essential issue for the design of high performance control strategy and set-up of a new welding schedule. However the RSW is a nonlinear time-varying uncertain process which couples the thermal, electrical, mechanical and metallurgical dynamics. To understand this complicated physical phenomenon an M-series pseudo-random electrical pattern is adopted to excite the RSW electrical-thermal dynamics and the thermal response is recorded according to the welding power outputs. Based on the experimental information the transfer function of an RSW electrical-thermal mechanism is identified, and the optimum model order and parameters are determined. Subsequently a control-oriented RSW model is established to explore the welding power control algorithm. The simulated results from the control model show their agreement with the experimental data, which validates its feasibility for corresponding welding control.

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