kontaktkeevituse protsess/operatsioon liidetavate pindade kõrgsagedusvooluga kuumutamise ja nende kokkusurumisega või ilma selleta, a welding process that produces coalescence of metals by the heat obtained from the resistance of the workpieces to the flow of induced high-frequency welding current with or without application of pressure; the effect of high-frequency welding current is to concentrate the welding heat at the desired location