A New Software to Evaluate Preheat Temperature and Cost

Preheating is a method for preventing hard structures and cold cracking in fusion welding of steels. Its application requires time and money, so that an evaluation of minimal preheat temperatures may be interesting. The thermal, metallurgical and economic problems of preheating were studied in order to acquire the most complete and logical as possible knowledge of the phenomenon thus defined. On this basis an easy and flexible instrument was developed. Parameters involved in the evaluation of the preheating temperature (chemical composition, hydrogen content, plate thickness, heat input, steel strength, restraint) were investigated. Available methods for determining the preheating temperature are briefly listed. An Üwer-modified formula was developed. A method for evaluating preheating costs is given. The developed software is presented.