Kilogram-force per square centimetre

From HandWiki
(Redirected from Technical atmosphere)
Short description: Unit of pressure
Kilogram-force per square centimetre
Da Lat locomotive dials.JPG
Soviet-made pressure gauges using kgf/cm2
General information
Unit ofPressure
Symbolkgf/cm2 or at 
Conversions
1 kgf/cm2 in ...... is equal to ...
   SI units   98.06650 kPa
   FPS units   14.22334 psi
Pressure gauge from unknown source produced by ISGUS GmbH.
Pressure gauge from unknown source. Note the "square" instead of 2. (Olja means "oil" in Swedish)

A kilogram-force per centimetre square (kgf/cm2), often just kilogram per square centimetre (kg/cm2), or kilopond per centimetre square (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). It is also known as a technical atmosphere (symbol: at).[1][2]

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.

Pressure units
v · d · e Pascal Bar Technical atmosphere Standard atmosphere Torr Pounds 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 more likely be rendered as the equivalent SI unit, the picogram.

References