Electrohydraulic fettling of large castings - in plant surrounded by earthed housing contg. sound insulation material to protect workers from noise and electric fields

摘要

Conveyor system is employed to lower the castings into a bath of liq. located underneath an overhead bridge carrying an electrode connected to a pulse generator; and the electrode is lowered into the liq. to provide high voltage discharges between the castings and the electrodes. Noise suppression is achieved via a housing which surrounds the bridge. The housing consists of a grid frame supporting sound insulation panels. Each panel consists of two earthed metal trays, one located inside the other to form a box filled with bitumen mastic absorbing vibration. Workers are shielded from sound, vibration and electric fields during the fettling of castings up to or exceeding 40 tonnes wt.