Dimensional stability and durability are two of the key requirements placed upon the plungers and tubes used in the automated feeding process. Improvements have been made in the quality of consumable ceramics, but regular adjustments are still needed to allow for ceramic deformation and wear.
This form of intervention is now a thing of the past for users of ACT™ coatings. A thin layer of platinum is applied to the surface of the ceramic, which provides 100% shape retention, thus stabilising the forming process.
TUBE STIRRERS
Typical problems:
– Uneven wear on the bottom edge of the tube
– Deteriorating glass flow control
– Glass leakage during orifice ring changes
– Eroded wall thickness at the glass line
The solution:
a) a full ACT™ coating reaching above
the glass-line
b) a partial ACT™ coating around the bottom edge of the tube
Case histories:
– 18 months in TV glass
– 18 months in container glass
PLUNGERS
Typical problems:
– Deteriorating gob shape control
– Defects such as cord in the finished article
The solution:
– An ACT™ coating extending above the glass line
Case histories:
– 32 months in lead glass
– 20 months in opal glass
– 22 months in borosilicate glass