What fill fluids options are available, and in what applications would each be used?
Glycerine is the most common fill fluid. Because of its unique fluid properties, Glycerine has become the standard for liquid filled gauges (see “What is the purpose of liquid filling a gauge?”). Glycerine’s clarity, viscosity, stability, cost, solubility, low toxicity make Glycerine an ideal fluid for many applications. Mineral oils and silicone fluids are used when temperature extremes, chemical compatibility or viscosity fall outside of Glycerine use. Halocarbon is an inert fluid that is compatible with chlorine, oxygen service some high temperature applications. Keep in mind that Glycerine is not compatible with strong oxidizers such as oxygen, chlorine, hydrogen peroxide, or nitric acid. Glycerine & Silicone are explosive in contact with chlorine. Halocarbon is explosive in contact with aluminum and magnesium.
