Effective Thermal Efficiency
The effective thermal efficiency is the ratio between the heat actually transferred into the workpiece and the electrical power of the welding process. It indicates how much of the supplied energy really contributes to welding.
Physical-Chemical Mechanism of Action
The effective thermal efficiency (η) is defined as the ratio of the actual net heat transferred into the workpiece (Q_netto) to the electrical power (P_electric) of the welding process. Mathematically: η = Q_netto / P_electric.
Metallurgical Relevance & Risks in Welding
A low effective thermal efficiency means that much energy is lost and does not contribute to welding. This can lead to inefficient processes, increases energy costs, and can cause uneven cooling of the weld, which poses risks for cracks and hardness problems.
Shop Practice & Action Instructions
To maximize the effective thermal efficiency, it is important that the welding machine is correctly calibrated and the process is optimally adjusted. This includes careful control of voltage, current, and fume extraction. An effective thermal efficiency of at least 0.85 is targeted in many applications.