This is dictated by the wattage ofthe bulb and the application. Glass bulb sizesand shapes tend to be standardized through outthe world. The use of modern high-speedequipment utilized in Lumex manufacturingfacilities dictate the use of precision madeglass bulbs. The rest of the worlduse numbers expressed in millimeters. A bulbshown as T-6 in catalog designation is tubularin shape with 6.0 mm diameter.
Bulbs aremade mostly of leaded glass with lime orborosilicate classes used on special products.
Filament Length and Wire Diameter. The design parameters of wattage, intensity, life andbulb size dictate the diameter of the raw wireand the subsequent winding into coils. Theneed to pack sometimes 16-20 inches ofuncoiled filament into small tubes requires theuse of supports made mostly from molybdenumto prevent the filament from shorting out andtwist in itself. Tungsten wires, used vary from 6to 300 m in diameter. Uncoiled wire lengthsvary according to design but range from 3.5mm to 5.0 mm per operating volt.