Instruments for Measuring Pressure

See under Closed Bomb (or Vessel) and Instruments for Measuring Pressures Developed by Explosives or Propellants in Vol 3, C330-L to C345-R... 

U-tube vacuum gauges fiiied with mercury are the simpiest and most exact instruments for measuring pressure in the rough vacuum range (1013 to a... 

Detonation (and Explosion) Pressure, Determination of. A brief description is given in Vol 1, p XX and a more complete description is in Vol 3, pp C330-L to C345-R under "Closed Bomb (or Vessel) and Instruments for Measuring Pressures Developed by Explosives and Propellants . See also some Refs under Detonation (and Explosion), Pressure of... 

Manometer Instrument for measuring pressure essentially a U-tube partially filled with a liquid (usually water, mercury, or a light oil), so constructed that the amount of displacement of the liquid indicates the pressure being exerted on the instrument. 

Closed bomb (or vessel) and instruments for measuring pressure developed for expls and proplnts 3 C330—C345... 

Beryllium connections and contacts are employed for switchgear and relays. Beryllium oxide is used as substrata for electronic circuits. Cadmium is used in television and fluorescent light phosphors. Cadmium, nickel and mercury are employed in batteries such as "nicad" cells and mercury cells. Mercury is used in fluorescent lamps, electrical switches, and outdoor lamps, as well as instruments for measuring pressure, temperature, and density. Selenium is employed as a photoreceptor in copying machines, and as a semiconductor in rectifiers. Lead applications include lead add storage batteries, a component in color television glass, and, in its oxide form, use as a dielectric material. 

Methods and instruments for measuring pressure are available for 100 or less up to several thousand dollars. It should be emphasized that many pressure devices read pressure differences between the process stream and atmospheric pressure. 

Because instruments for measuring pressure, such as the manometer, often contain mercury, commonly used units for pressure are based on the height of the mercury column (in millimeters) that the gas pressure can support. The unit mm Hg is often called the torr in honor of the scientist, Evangelista Torricelli. A related unit for pressure is the standard atmosphere (abbreviated atm). 

COMPOUND GAUGE - Instrument for measuring pressures both above and below atmospheric pressure. 

Instrumentation for measuring pressure, normal and shear stresses, and flow rate from numerous... 

Many instruments for measuring pressures in liquids measure only the increase in pressure over the pressure at the surface. Therefore, p in equation [5.28] is sometimes referred to as the absolute pressure and p — po as the gauge pressure. 

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