ABSTRACT
Manufactured carbon is often used in metering devices. Metering devices handling foodstuffs generally operate at lower speeds and higher contact pressures than those in gasoline pumps. A special case of metering is the use of orifices or nozzles for throttling the flow of extremely corrosive or high-temperature fluids. Dimensional stability, resistance to chemical corrosion, and moldability are the three most important considerations in selecting carbon grades for any metering device. Most meters must be capable of handling a wide range of fluids. The choice of a carbon grade that can be molded to size is important for parts having irregularly shaped cavities or ports. Meters are precision instruments and should be treated with the care and respect due any instrument. The carbons taken from the meter should also be examined for evidence of high contact pressures at drive points such as ears or notches.
