Computational modeling of quenching step of a coated steel pipe with thermo-elastic, thermo-plastic and thermo-viscoelastic models: Impact of masking tape at tube ends

摘要

The relevance of three numerical thermo-mechanical models of materials behavior is investigated to assess stresses magnitudes stored in three layers polyethylene coating during the quenching step of a coated steel pipe. Computations results stemming from thermo-elastic, thermo-plastic and thermoviscoelastic models are compared. Benefits of thermo-plastic or thermo-viscoelastic model are clearly demonstrated, since free edge effect appears negligible. Far from assembly's edges, interfacial stresses levels are less than 5 MPa at steel/fusion bonded epoxy (FBE) interface and less than 16 MPa at FBE/polyethylene adhesive interface. This work proves that thermo-viscoelastic model is the most suitable modeling especially because computed interfacial shear strengths are consistent with ground feedback. Thermo-viscoelastic model predicts as well realistic values of stress singularity that does exist at tubes ends. Moreover, for the first time, the impact of the masking tape deposited on steel pipe ends to ease cutback preparation step on stresses distribution inside this multilayer system is studied. The presence of this masking tape both allows to shift and halve the maximal stresses concentration zone.