Kilogram-force per square centimetre
A kilogram-force per centimetre square (kgf/cm2), often just kilogram per square centimetre (kg/cm2), or kilopond per centimetre square 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). It is also known as a technical atmosphere (symbol: at).[1][2]
Kilogram-force per square centimetre | |
---|---|
Soviet-made pressure gauges using kgf/cm2 | |
General information | |
Unit of | Pressure |
Symbol | kgf/cm2 or at |
Conversions | |
1 kgf/cm2 in ... | ... is equal to ... |
SI units | 98.06650 kPa |
FPS units | 14.22334 psi |
The kilogram-force per square centimetre remains active as a measurement of force 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 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.
Pascal | Bar | Technical atmosphere | Standard atmosphere | Torr | Pound per square inch | |
---|---|---|---|---|---|---|
(Pa) | (bar) | (at) | (atm) | (Torr) | (lbf/in2) | |
1 Pa | ≡ 1 N/m2 | 10−5 | 1.0197×10−5 | 9.8692×10−6 | 7.5006×10−3 | 0.000 145 037 737 730 |
1 bar | 105 | ≡ 100 kPa
≡ 106 dyn/cm2 |
1.0197 | 0.98692 | 750.06 | 14.503 773 773 022 |
1 at | 98066.5 | 0.980665 | ≡ 1 kgf/cm2 | 0.967 841 105 354 1 | 735.559 240 1 | 14.223 343 307 120 3 |
1 atm | ≡ 101325 | ≡ 1.01325 | 1.0332 | 1 | 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 | 1 Torr
≈ 1 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 | ≡ 1 lbf/in2 |
1 at = 98.0665 kPa ≈ 0.96784 standard atmospheres
Ambiguity of at
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 be more likely be rendered as the equivalent SI unit, the picogram.
References
- Dorf, Richard C. (2003-11-24). CRC Handbook of Engineering Tables. CRC Press. ISBN 9780203009222.
- Suplee, Curt (2009-07-02). "Special Publication 811". NIST. Retrieved 2019-05-17.
- The NIST Guide for the use of the International System of Units, National Institute of Standards and Technology, 18 Oct 2011