Oil and Gas: Terms & Glossary (5)

G-fin	A U-shaped exchanger having a pipe within a pipe. Also known as a "hair pin" or "double pipe" exchanger.
Gas	The physical state of matter having the ability to diffuse readily and distribute uniformly throughout the container to which it is confined.
Gasket	Any of a wide variety of materials placed between mating surfaces to prevent leaks.
Gate valve	Valve designed for on or off control of a commodity flowing through a pipe.
Gauge	Instruments that measure the liquid level inside a vessel or the temperature and/or pressure in a piping system.
Globe valve	Valve designed to allow for the throttling of commodities flowing through a pipe.
Grade	The true or predetermined elevation of the ground-supported surface of a piping facility.
Grade beam	Structural member used to support grating or other flooring material at ground (grade) level
Gravity flow system	Piping system constructed of sloped pipes that uses gravity as a means of moving the commodity inside.
Grout	A concrete mixture poured on the tops of equipment foundations to provided final leveling.
Guide	Type of pipe support that permits longitudinal but not lateral movement.
Hand rail	Protective railing around platforms. Typically 3'-0" tall.
Hanger	Pipe support used on horizontal pipes that will suspend the pipe from a stationary object from above.
Head	The end enclosure of a vessel.
Header	The main run of pipe from which branches are connected.
Headroom	Vertical measurement that provides overhead clearances.
Heater	Piping equipment that uses a combustible material to increase the temperature of a commodity.
Heat exchanger	Piping equipment used to transfer heat from one fluid source to another without the two fluids mixing together
Hydrocarbon	Any solid, liquid, or gaseous compound whose molecular structure is made exclusively of hydrogen and carbon molecules.
Impeller	Rotating device in a pump that forces the incoming commodity to be expelled at a greater pressure.
Indicator	A device used to indicate the liquid level, temperature, pressure or flow rate inside a piping system.
Instrument	One of many monitoring devices that can sense, measure, transmit, or control.
Instrument air	Piping system containing clean air used to operate instrumentation throughout a piping facility,
Instrumentation	The use of monitoring instruments to perform duties not permissible by human workers.
Insulation	Exterior covering on pipe or equipment that maintains a constant temperature. Also protection for workers from high temperature surfaces.
Insulation rings	Continuous circular rings welded to the exterior of a vertical vessel that support a vessel's insulation typically spaced on 12'-0" centers.
Knockout drum	Piping equipment used to separate gases from liquids.
Ladder	Climbing apparatus that allows access to piping components at extreme elevations.
Level Alarm	Instrument that detects high or low liquid levels within a vessel and alerts plant operators with an audible or visual signal.
Level gauge (glass)	A vertical transparent tube connected to the external surface of a vessel that allows visual inspection of internal liquid levels.
Level indicating controller	Instrument that indicates the liquid level of a vessel and can control the liquid level by transmitting signals to a control valve.
Level recorder	Makes a permanent record of liquid level in a vessel.
Level recording controller	Instrument that records the liquid level of a vessel and can control the liquid level by transmitting signals to a control valve.
Lifting lugs	Donut-shaped rings welded to the vessel's shell or head that allow the vessel to be raised and positioned during installation.
Line	Generic name given to reference a completed piping configuration.
Liquid	The physical state of matter possessing flow characteristics and minimal compressibility.

Oil and Gas: A Practical Handbook