Anti-implosion ring for television tubes - comprises steel ring coated with aluminium and then baked enamel for protection against corrosion

摘要

A coating which provides protection against corrosion is applied to an anti-implosion frame employed on television tubes. Frame is a ring of steel strip, which is coated with a layer of Al by a conventional immersion process, followed by a layer of baked enamel. The Al is pref. 20-50 mu m thick, and applied using Al with a m. of 650 degrees C and the enamel is pref. 50-120 mu m thick baked on the Al at is approx. 550 degrees C. Process economically provides a coating which resists the temp. of 500 degrees C used to shrink the ring onto the television tube. During shrinking-on, the enamel is in a tough, pasty state so it moves to match any slight out-of-roundness of the glass tube so a uniform pressure is exerted round the entire periphery of the tube.