Kilogram-force Per Square Centimetre - Wikipedia

Unit of pressure

Kilogram-force per square centimetre
Soviet-made pressure gauges using kgf/cm2
General information
Unit of	Pressure
Symbol	kgf/cm2, at
Conversions
1 kgf/cm2 in ...	... is equal to ...
SI units	98.06650 kPa
FPS units	14.22334 psi

A kilogram-force per square centimetre (kgf/cm2), often just kilogram per square centimetre (kg/cm2), or kilopond per square centimetre (kp/cm2) is a deprecated unit of pressure using metric units. It is not a part of the International System of Units (SI), the modern metric system. 1 kgf/cm2 equals 98.0665 kPa (kilopascals) or 0.980665 bar—2% less than a bar. It is also known as a technical atmosphere (symbol: at).[1][2]

Use of the kilogram-force per square centimetre continues primarily due to older pressure measurement devices still in use.

This use of the unit of pressure provides an intuitive understanding for how a body's mass, in contexts with roughly standard gravity, can apply force to a scale's surface area, i.e. kilogram-force per square (centi-)metre.

In SI units, the unit is converted to the SI derived unit pascal (Pa), which is defined as one newton per square metre (N/m2). A newton is equal to 1 kg⋅m/s2, and a kilogram-force is 9.80665 N,[3] meaning that 1 kgf/cm2 equals 98.0665 kilopascals (kPa).

In some older publications, kilogram-force per square centimetre is abbreviated ksc instead of kg/cm2.

Pressure units

v t e	Pascal	Bar	Technical atmosphere	Standard atmosphere	Torr	Pound per square inch
	(Pa)	(bar)	(at)	(atm)	(Torr)	(lbf/in2)
1 Pa	—	1 Pa = 10−5 bar	1 Pa = 1.0197×10−5 at	1 Pa = 9.8692×10−6 atm	1 Pa = 7.5006×10−3 Torr	1 Pa = 0.000145037737730 lbf/in2
1 bar	105	—	= 1.0197	= 0.98692	= 750.06	= 14.503773773022
1 at	98066.5	0.980665	—	0.9678411053541	735.5592401	14.2233433071203
1 atm	≡ 101325	≡ 1.01325	1.0332	—	760	14.6959487755142
1 Torr	133.322368421	0.001333224	0.00135951	⁠1/760⁠ ≈ 0.001315789	—	0.019336775
1 lbf/in2	6894.757293168	0.068947573	0.070306958	0.068045964	51.714932572	—

1 at	= 98.0665 kPa
	≈ 0.96784 standard atmospheres

Pressure gauge from unknown source produced by ISGUS GmbH.Pressure gauge from unknown source. Note the visual square instead of 2. (Olja means "oil" in Swedish)

Ambiguity of at

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The symbol "at" clashes with that of the katal (symbol: "kat"), the SI unit of catalytic activity; a kilotechnical atmosphere would have the symbol "kat", indistinguishable from the symbol for the katal. It also clashes with that of the non-SI unit, the attotonne, but that unit would more likely be rendered as the equivalent SI unit, the picogram.

References

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1. ^ Dorf, Richard C. (2003-11-24). CRC Handbook of Engineering Tables. CRC Press. ISBN 9780203009222.
2. ^ Suplee, Curt (2009-07-02). "Special Publication 811". NIST. Retrieved 2019-05-17.
3. ^ The NIST Guide for the use of the International System of Units, National Institute of Standards and Technology, 18 Oct 2011