摘要 |
A method of sensing the presence and proper positioning of an annular sealing gasket encircling the neck of a closure flange employed in the fabrication of steel shipping drums. The closure flange consists of an upstanding internally threaded cylindrical neck surrounded by a laterally extending noncircular base at its lower end. An annular, resilient sealing gasket is placed over the flange neck so as to seat above the flange base. The gasket is sensed for presence and proper positioning as the flange moves along a predetermined path with automatic ejection of improperly gasketed flanges. |