Course No. 35
Level Measurement – Differential Pressure
Fundamentals of pressure as related to liquid columns and atmospheric pressure; gauge pressure, specific gravity and conversion from one unit of pressure to another; U-tube and well-type manometers; differential pressure; instrument manifold with proper valving procedures; measuring liquid level with a manometer, level within vessel and below the vessel; conversions for various manometer fluids; seal fluids and balancing legs; liquid level measurement in a pressurized vessel; use of condensate leg when measuring level in vessel with vapor gas spaced; principles of purging instrument process lines; bellows-type pressure elements; effect of gas in instrument liquid lines; using diaphragms as pressure measuring elements; flapper-ball-end dip-tube level instrument, and bubbler dip-tube level device on open and pressurized vessels.
Prerequisites: Familiarity with sight and float instruments and buoyancy displacers.