Influence of boiling heat transfer and phase transformations on the deformation of a steel tube during quenching by impinging water jets

To understand how tube bending occurs during the quenching by a water jet, an experimental device has been designed to measure heat transfer, tube bending and to visualize the hydrodynamics of the liquid jet during the cooling of a hot steel tube (grade: 42CrMo4, length: 500 mm, diameter: 76 mm, thickness: 6 mm). The bending resulting from the thermal gradients and phase transformations inside the tube is also measured all along its cooling. Knowing the heat transfer at the wall as a function of the wall surface temperature allowed us to compute the time evolution of temperature, phase transformations and deformations using SYSWELD code. This coupled analysis allows us to better understand why bending can occur in industrial processes.