Influence of repair welds on the weld-joint properties

V predstavljenem delu smo preučevali vpliv reparaturnega varjenja na mehanske lastnosti in zaostale napetosti. Poseben problem so začetki in konci reparaturnih zvarov. Reparaturni zvari so po večini kratki, varimo pa jih na že obstoječi var. Lokalno se spremenijo lastnosti materiala vara, ki v kombinaciji s škodljivimi nateznimi zaostalimi napetostmi lahko pomenijo nevarnost za pojav kthkega loma. V tej raziskavi so bile zaostale napetosti izmerjene pred reparaturnim varjenjem in po njem ter nato primerjane med seboj. Po reparaturnem varjenju dobimo bolj neugodno porazdelitev zaostalih napetosti, ki jim je treba posvetiti posebno pozornost.The influence of repair welding on the mechanical properties and residual stresses has been studied. Special problems are associated with the start and end of repair welds. Repair welds are usually short and they are deposited on an existing weld. The mechanical properties can be changed. The interaction between the weak material and the harmful tensile residual stresses increases the risk of brittle fracture. Residual stresses were measured before and after repair welding and compared with each other. The distribution of residual stresses after repair welding is more inconvenient than before the repair welding. This is the reason why special attention has to be paid to this distribution