A heater with electric resistance, steam, or hot water heating elements to heat the air. Natural or forced draft units are designed for wall mounting.
|
A heater with electric resistance, steam, or hot water heating elements to heat the air. Natural or forced draft units are designed for wall mounting.
|
Related Terms |
GAGE VALVEA valve attached to a water column or drum for checking water level. |
WATER COLUMNA vertical tubular member connected at its top and bottom to the steam and water space respectively to a boiler, to which the water gage, gage valves, high and low water alarms and fuel cutoff may be connected. |
TRY VALVESTest valves on a water column used to verify the water level when the gauge glass is out of service. |
TRY VALVEOne of three valves mounted on a boiler or water column within the visible range of the gauge glass and used to check the water level. |
SOUNDING PIPEA pipe leading to the bottom of an oil or water tank, for guiding a sounding tape or jointed rod when measuring the depth of liquid in the tank. |
SHALLOW WATER EFFECTThe effect that due to the depth of water, the speed of the vessel and shape of the vessel's hull causes the vessel to sink deeper in the water especially in shallow water and at high speed. The vessel becomes sluggish in responding to the rudder. |
PNEUMATIC CAISSON
A caisson having a chamber filled with compressed air at a pressure equal to the pressure of the water outside.
|
PHOTOTUBE CURRENT METER
A device for measuring the speed of water currents in which a perforated disk, which rotates with the current by means of a propeller, is placed in the path of a beam of light that is then reflected from a mirror onto a phototube.
|
PHLEGER CORER
A device for obtaining ocean bottom cores up to about 4 feet (1.2 meters) in length; consists of an upper tube, main body weight, and tailfin assembly with a check valve that prevents the flow of water into the upper section and a consequent washing out of the core sample while hoisting the corer.
|
PERMISSIBLE VELOCITY
The highest velocity at which water is permitted to pass through a structure or conduit without excessive damage.
|
MarineProHelp 2018 - 2021