Diameter and tolerance
The diameter of tungsten filament is generally expressed in millimeters (mm) or inches (inches). Generally, thinner tungsten wires with diameters of 0.02mm to 0.5mm are measured by weight per unit length, that is, expressed as the weight of tungsten wire per 200 mm (mg/200mm). The standard diameter tolerance is 3% of the weight standard, and tighter tolerances can be achieved, depending on the application of the tungsten wire product.
Thicker tungsten wires with diameters of 0.5mm to 6.5mm are measured in millimeters (mm), and the tolerance is expressed as a percentage of the diameter, with a standard tolerance of 1.5%.
