pideva töörežiimiga tõukurahi, milles materjalide või toorikute transportimine toimub ahju põranda moodustavatel paralleelsetel rullikutel, a modification of the pusher-type continuous furnace that provides for rollers in the hearth or muffle of the furnace whereby friction is greatly reduced and lightweight trays can be used repeatedly without risk of unacceptable distortion and damage to the work