Pound-force per square inch
|Unit name||Pound-force per square inch|
|Physical quantity (s)||pressure|
|system||Anglo-American system of measurement|
|In SI units|
|Derived from||Pound-force , square inch|
Pound-force per square inch , or pounds per square inch (" pounds per square inch "), is a unit of measurement commonly used in the United States for pressure . It is a unit of the Anglo-American system of measurement that does not belong to the international system of units (SI) . It is used in the USA for pressure specifications in everyday life. One example is tire pressure . The SI unit Pascal is mostly used in science .
Pound-force per square inch is defined as the pressure exerted by the weight of a mass of one Anglo-American pound (lb) at standard acceleration on an area of one square inch. The designation of the unit is lb.p.sq.in., psi or psi for short . This is short for "pound-force per square inch".
Conversion into other units of the Anglo-American system of measurement:
In the opposite direction, the conversion factor is:
Often the unit is specified even more precisely with psia (pounds-force per square inch absolute) for the absolute pressure or psig (pounds-force per square inch gauge) for the relative pressure (overpressure) To characterize the pressure measurement method, according to the - outdated - German terms ata and atü for atmosphere absolute or overpressure.
For larger pressures or tensions, the unit kilopound per square inch (ksi) (1 ksi = 1000 psi) is used in some cases .