100 Pounds Per Square Inch

Unit of pressure or stress

Pound per square inch
A pressure judge reading in psi (ruddy calibration) and kPa (black scale)
General information
Unit system	Imperial units, U.s. customary units
Unit of	Pressure, Stress
Symbol	psi or lbf/in²
Conversions
1 psi in ...	... is equal to ...

SI units	6.894757 kPa

The pound per square inch or, more accurately, pound-strength per foursquare inch (symbol: lbf/in² ;^[1] abbreviation: psi) is a unit of pressure or of stress based on avoirdupois units. It is the force per unit area resulting from a strength of 1 pound-force applied to an surface area of one square inch. In SI units, one psi is approximately equal to 6895 Pa.

Pounds per foursquare inch absolute (psia) is used to brand it clear that the pressure is relative to a vacuum rather than the ambient atmospheric pressure. Since atmospheric pressure at sea level is around 14.7 psi (101 kilopascals), this will be added to whatever pressure reading made in air at body of water level. The antipodal is pounds per square inch estimate (psig), indicating that the force per unit area is relative to atmospheric pressure. For example, a bicycle tire pumped up to 65 psig in a local atmospheric force per unit area at sea level (14.7 psi) volition have a pressure of 79.7 psia (14.7 psi + 65 psi).^[2] ^[three] When gauge force per unit area is referenced to something other than ambience atmospheric pressure, then the units would exist pounds per foursquare inch differential (psid).

Multiples [edit]

The kilopound per square inch (ksi) is a scaled unit derived from psi, equivalent to a thousand psi (1000 lbf/in^two).

ksi are not widely used for gas pressures. They are generally used in materials science, where the tensile force of a fabric is measured as a large number of psi.^[4]

The conversion in SI units is one ksi = six.895 MPa, or i MPa = 0.145 ksi.

The megapound per square inch (Mpsi) is some other multiple equal to a million psi. It is used in mechanics for the rubberband modulus of materials, especially for metals.^[five]

The conversion in SI units is ane Mpsi = 6.895 GPa, or 1 GPa = 0.145 Mpsi.

Magnitude [edit]

Inch of water: 0.036 psid
Blood pressure – clinically normal human blood pressure level (120/fourscore mmHg): 2.32 psig/1.55 psig
Natural gas residential piped in for consumer appliance; 4–half-dozen psig.
Boost force per unit area provided by an automotive turbocharger (mutual): 6–fifteen psig
NFL football: 12.5–13.5 psig
Atmospheric pressure at sea level (standard): xiv.vii psia
Automobile tire overpressure (mutual): 32 psig
Bicycle tire overpressure (common): 65 psig
Workshop or garage air tools: ninety psig
Air brake (runway) or air brake (route vehicle) reservoir overpressure (common): 90–120 psig
Road racing bicycle tire overpressure: 120 psig
Steam locomotive burn down tube banality (UK, 20th century): 150–280 psig
Union Pacific Big Male child steam locomotive banality: 300 psig
United states of america Navy steam boiler pressure: 800 psi
Natural gas pipelines: 800–1000 psig
Full SCBA (cocky-independent animate apparatus) for IDLH (non-fire) atmospheres: 2216 psig
Nuclear reactor chief loop: 2300 psi
Full SCUBA (self-independent underwater animate apparatus) tank overpressure (common): 3000 psig
Full SCBA (self-independent breathing apparatus) for interior firefighting operations: 4500 psig
Airbus A380 hydraulic system: 5000 psig
Land Rover Td5 diesel engine fuel injection pressure: 22,500 psi
Ultimate forcefulness of ASTM A36 steel: 58,000 psi
Water jet cutter: forty,000–100,000 psig

Conversions [edit]

The conversions to and from SI are computed from exact definitions just issue in a repeating decimal. ^[6] ^[7]

$P_{\text{Pa}}=P_{\text{PSI}}\times {\frac {(0.45359237~{\text{kg}}\times 9.80665~{\text{g}}/{\text{s}}^{2})/{\text{lbf}}}{(0.0254~{\text{thousand}}/{\text{in}})^{2}}}$

$P_{\text{PSI}}=P_{\text{Pa}}\times {\frac {(0.0254~{\text{m}}/{\text{in}})^{2}}{(0.45359237~{\text{kg}}\times 9.80665~{\text{m}}/{\text{s}}^{2})/{\text{lbf}}}}$

As the pascal is a very minor unit of measurement relative to industrial pressures, the kilopascal is commonly used. k kPa ≈ 145 lbf/inⁱⁱ.

Approximate conversions (rounded to some arbitrary number of digits, except when denoted by "≡") are shown in the following tabular array.

Pressure level units
v t e	Pascal	Bar	Technical atmosphere	Standard atmosphere	Torr	Pound per foursquare inch
v t e	(Pa)	(bar)	(at)	(atm)	(Torr)	(lbf/inⁱⁱ)
i Pa	i Pa ≡ 1 Pa	1 Pa = x^−v bar	ane Pa = i.0197×10^−five at	1 Pa = ix.8692×x^−six atm	1 Pa = 7.5006×10⁻³ Torr	1 Pa = 0.000 145 037 737 730 lbf/in²
1 bar	10⁵	≡ 100 kPa ≡ 10^half-dozen dyn/cm²	= one.0197	= 0.98692	= 750.06	= xiv.503 773 773 022
1 at	98066.v	0.980665	≡ 1 kgf/cm²	0.967 841 105 354 1	735.559 240 1	14.223 343 307 120 3
one atm	≡ 101325	≡ one.01325	1.0332	one	760	14.695 948 775 514 2
1 Torr	133.322 368 421	0.001 333 224	0.001 359 51	1 / 760 ≈ 0.001 315 789	one Torr ≈ one mmHg	0.019 336 775
1 lbf/in²	6894.757 293 168	0.068 947 573	0.070 306 958	0.068 045 964	51.714 932 572	≡ ane lbf/in^two

See as well [edit]

Conversion of units: Pressure or mechanical stress
Pressure: Units

References [edit]

^ IEEE Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch-Pound Units, and Sure Other Units), IEEE Std 260.1™-2004 (Revision of IEEE Std 260.ane-1993)
^ "Glossary of Industrial Air Cleaning Technology". United Air Specialists, Inc. Archived from the original on Baronial i, 2011.
^ "Gage v. Sealed five. Accented pressure" (PDF). Dynisco.
^ "Tensile Forcefulness of Steel and Other Metals". All Metals & Forge Grouping. 18 Apr 2013. Retrieved 2016-07-26 . A metal'due south yield strength and ultimate tensile forcefulness values are expressed in tons per square inch, pounds per square inch or thousand pounds (KSI) per square inch. For example, a tensile strength of a steel that can withstand 40,000 pounds of strength per square inch may be expressed as 40,000 PSI or twoscore KSI (with Thousand being the [multiplier] for thousands of pounds). The tensile strength of steel may as well be shown in MPa, or megapascal.
^ "An example of the employ of Mpsi in mechanics for the elastic moduli of several materials". Archived from the original on 2016-12-16. Retrieved 2015-06-06 .
^ BS 350: Office i: 1974 – Conversion factors and tables. British Standards Establishment. 1974. p. 49. ISBN0-580-08471-Ten.
^ NIST Special Publication 811 – Guide for the Use of the International System of Units (SI) (PDF). National Institute of Standards and Technology. 2008. p. 66.