P. Kavitha

Insight into Arc Welding Power Source Terminologies

Welding arc is an electric current flowing between two electrodes through an ionized gas column. Arc stability is a critical problem which influences the metal transfer during welding. When the arc is stable, metal transfer is uniform with minimum spatter (Shklovski and Janson in Development of constant-power source for arc welding, pp. 255–258, 2012 [37]). The terminologies of major concerns during the joining process are presented below.

Welding an Overview

This book categorically presents the mechanical, metallurgical and electrical terminologies and the associated science for welding power sources. Key focus is laid on arc welding processes owing to its growing demand in versatile applications. Figure 1.1 illustrates the types of welding processes.

Power Sources and Challenges for Different Arc Welding Processes

The choice of power source is based on the working principle of joining technique and the material type to be welded. Power sources for various arc welding process are discussed in the following sections.

Sensors for Welding Data Acquisition

Sensors in arc welding process can obtain information about the geometry and position of the workpiece, electrical parameters like voltage, current, wire feed rate, in addition to providing suitable form of control over the welding process parameters. The weld quality mainly depends on weld parameters like current, voltage, wire speed and wire feed rate. The welding torch also influences the flow of the material. The input heat for melting the component and constant heat flow is directly related with the welding torch control and it further influences the weld quality. This chapter presents the fundamental knowledge on data acquisition in arc welding process with real-time case study illustrations.

Optimization in Arc Welding Process

Optimization is a valuable tool in making decisions and in analysing physical systems. In mathematical terms, optimization is the process of determining the best solution achievable close to desired value among the set of all feasible solutions.

Codes and Safety Standards During Welding

Arc welding becomes a safe procedure when adequate safety precautions are considered and followed to protect the workers from harmful hazards. When such safety measures are neglected, the workers come across potential hazards such as exposure to gases and fumes, arc radiation, electric shock and fire accidents, which could be serious and fatal.

Control Terminologies and Schemes for Arc Welding Processes

A control system interconnects various components of a system to provide a desired response. The control theory provides a foundation for analysing a system, which indicates cause–effect (input–output) relationship for various elements involved in a system.