Petrophysical Training
Licenses
|
 SYSTEMS
OF UNITS -- THE BASICS
Units of measurement cannot
be avoided in the practice of petrophysics, nor in our ordinary life. Different
systems are used in different countries, in different industries, and even in
different cultures in the same communities -- gets confusing. One of the best
known and least used unit of measurement is the cubit. It is defined as the
distance from the elbow to the tip of the longest finger. My personal cubit is
right on 18 inches. Yours is probably different. Similarly, the English foot is
slightly smaller than the French foot -- the respective Kings had different
sized feet. To get around these problems, standards have been established and
most countries except the USA have adopted them for personal, commercial, and
scientific arenas.
This page covers most of what you need to survive in the oil and gas industry.
Descriptions of Systeme Internatuinal or SI units, oilfield units, and
conversions between them follow this introduction,
Some
commonly used words that predate the SI units have different
meanings in different parts of the world, and some abbreviations
(for example the letter "M") have more than one meaning. Here is a
;list of the common problem words:
American
British/French/German Prefix
Abbreviation Factor
thousand
thousand
Kilo k
10^3
million
million
Mega M
10^6
billion
milliard
Giga G
10^9
trillion
billion
Tera T
10^12
quadrillion
–
Peta P
10^15
quintillion trillion
Exa E
10^18
sextillion
–
Zetta Z
10^21
septillion
quadrillion
Yolta Y
10^24
In many industries, the Roman numeral M, meaning 1000 and MM meaning
1 million were, and still are, widely used, not to be confused with
the SI prefix M, meaning 1 million. Sometimes MM is shown in lower
case as mm (for example mmcf/d, meaning 1 million cubic feet per
day), not to be confused with the SI unit mm (millimeter). The SI
prefix k, meaning 1000, is often written as a capital letter K, in
keeping with the capitalization of many other prefixes for positive
powers of 10 (for example M, G, T. etc).
There is no shortage of obsolete units of measurement, some still
in wide use, such as nautical miles and knots in the ship and
airline transportation. Some may be found in surveying, especially
in non-English speaking countries. Here are some of the most common:
1 nautical mile = 1.1508 miles = 1/60 degree of latitude on Earth
1 knot = 1.1508 miles per hour
1 fathom = 6.0 feet = 1.829 meters
1 league = 5.556 km = 3.452 miles = 3 nautical miles
1 league (area) = 4.428 acres = 1.792 hectares
Some older survey plats may use these tems:
1 rod = 16.5 feet = 0.25 chains = 1 perch = 1 pole
1 chain = 4 rods = 20.17 meters = 66 feet = 100 links = 1/80 mile
1 furlong = 10 chains = 201.168 meters = 660 feet = 1/8 mile
These French measurements nay be found in Quebec an Louisiana and
other early French settlements in the Americas.
1 pied = 1.0 French foot = 12.789 inches = 0.3248 meters = 1.0657
feet
1 loise = 6.0 pied = 1.949 meters = 6.394 feet
1 perche = 3 loise = 18.0 pieds = 5.847 meters = 19.183 feet
1 arpent = 10 perches = 30 loise = 180 pieds = 58.47 meters = 191.83
feet
1 arpent (area) = 3418.9 sq meters = 0.845 acres = 36 800 sq feet
Unfortunately, much of the work done in the oilfields uses a mixed
set of units composed of British units (called English units in this
Handbook) , CGS Units (an early form of metric units), and SI Units
(called Metric units in this Handbook). Examples of English units
are the foot, mile, and pound. Examples of Metric units are the
meter, kilometer, and kilogram. Conversion back and forth between
sets of units is a constant task for a petrophysicist.
A
lengthy list of conversions is available at the bottom of this page.
A useful freeware units conversion calculator can be downloaded
HERE. This is an executable
(.EXE) wrapped in a .ZIP file and may be blocked by your security settings.
INTERNATIONAL SYSTEM
OF UNITS (SI)
SI units are
widely used in scientific work. All the SI fundamental units and
derived units are listed on this page, as well as the universal
constants. Prefixes are applied to the SI names of units to indicate
multipliers of the basic unit
|
SI Prefixes |
| Factor |
Name |
Symbol |
| 1024 |
yotta |
Y |
| 1021 |
zetta |
Z |
| 1018 |
exa |
E |
| 1015 |
peta |
P |
| 1012 |
tera |
T |
| 109 |
giga |
G |
| 106 |
mega |
M |
| 103 |
kilo |
k |
| 102 |
hecto |
h |
| 101 |
deka |
da |
|
|
| Factor
|
Name
|
Symbol
|
| 10-1 |
deci |
d |
| 10-2 |
centi |
c |
| 10-3 |
milli |
m |
| 10-6 |
micro |
µ |
| 10-9 |
nano |
n |
| 10-12 |
pico |
p |
| 10-15 |
femto |
f |
| 10-18 |
atto |
a |
| 10-21 |
zepto |
z |
| 10-24 |
yocto |
y |
|
|
LIST OF SI UNITS |
| UNIT |
SYMBOL |
DERIVATION |
BASE UNITS |
REPRESENTING |
| ampere |
A |
-- |
A |
electric current |
| becquerel |
Bq |
1/s |
s-1 |
activity |
| candela |
cd |
-- |
cd |
luminous intensity |
| coulomb |
C |
A s |
A s |
charge |
| farad |
F |
A s/V |
kg-1 m-2
s4 A2 |
capacitance |
| gray |
Gy |
J/kg |
m2 s-2 |
absorbed dose |
| henry |
H |
V s/A |
kg m2 s-2
A-2 |
inductance |
| hertz |
Hz |
1/s |
s-1 |
frequency |
| joule |
J |
N m |
kg m2 s-2 |
energy |
| kelvin
[footnote 1] |
K |
-- |
K |
temperature |
| kilogram |
kg |
-- |
kg |
mass |
| lumen |
lm |
cd sr |
cd sr |
luminous flux |
| lux |
lx |
lm/m2 |
cd sr m-2 |
illumination |
| metre |
m |
-- |
m |
length |
| mole |
mol |
-- |
mol |
amount of substance |
| newton |
N |
kg m/s2 |
kg m s-2 |
force |
| ohm |
O
[footnote 2] |
V/A |
kg m2 s-3
A-2 |
resistance |
| pascal |
Pa |
N/m2 |
kg m-1 s-2 |
pressure |
| radian |
rad |
-- |
rad |
plane angle |
| second |
s |
-- |
s |
time |
| siemens |
S |
1/O |
kg-1 m-2
s3 A2 |
electric conductance |
| sievert |
Sv |
J/kg |
m2 s-2 |
dose equivalent |
| steradian |
sr |
-- |
sr |
solid angle |
| tesla |
T |
Wb/m2 |
kg s-2 A-1 |
magnetic flux density |
| volt |
V |
W/A |
kg m2 s-3
A-1 |
voltage |
| watt |
W |
J/s |
kg m2 s-3 |
power |
| weber |
Wb |
V s |
kg m2 s-2
A-1 |
magnetic flux |
|
Non-SI unit
approved for use with SI. |
| UNIT |
SYMBOL |
Value in SI Units |
| minute |
min |
60 s |
| hour |
h |
60 min = 3600 s |
| day |
d |
24 h = 86 400 s |
| degree |
deg |
(pi/180)
rad |
| arcminute |
', arcmin |
(1/60) deg = (pi/10
800) rad |
| arcsecond |
", arcsec |
(1/60)' = (pi/648
000) rad |
| litre |
l, L
[footnote 4] |
1 dm3 =
10-3 m3 |
| tonne |
t |
103 kg |
| electronvolt |
eV |
(1.602 177 33 +-
0.000 000 49) x 10-19 J |
| unified atomic mass unit |
u |
(1.660 540 2 +-
0.000 001 0) x 10-27 kg |
| nautical mile |
-- |
1852 m |
| knot |
-- |
1 nautical mile
per hour = (1852/3600) m/s |
| angstrom |
A
[footnote 5] |
10-10 m |
| are |
a |
1 dam2
= 102 m2 |
| hectare |
ha |
104 m2 |
| barn |
b |
10-28 m2 |
| bar |
bar |
105 Pa |
| gal |
Gal |
10-2
m/s2 |
| curie |
Ci |
3.7 x 1010
Bq |
| roentgen |
R |
2.58 x 10-4
C/kg |
| rad |
rd, rad |
10-2 Gy |
| rem |
rem |
UNIVERSAL CONSTANTS (SI Units)-
|
UNIVERSAL CONSTANTS |
|
CONSTANT |
SYMBOL |
VALUE
and UNITS |
| acceleration
due to gravity |
g
|
9.806 65 m/s2 |
| age of
Universe |
t0
|
15(5) Gy |
| atomic mass
unit, unified |
u |
931.494 32(28) MeV/c2
=
1.660 540 2(10) x 10-27 kg |
| astronomical
unit |
au |
1.495 978 706 6(2) x
1011 m |
| Avogadro
constant |
NA
|
6.022 136 7(36) x 1023
mol-1 |
| Bohr magneton
|
muB
|
5.788 382 63(52) x 10-11
MeV/T |
| Bohr radius
|
aoo
|
0.529 177 249(24) x
10-10 m |
| Boltzmann
constant |
k
|
1.380 658(12) x 10-23
J/K =
8.617 385(73) x 10-5 eV/K |
| cosmic
background energy density |
rhogamma
|
4.647 7 x 10-34
(T/2.726 K)4 g/cm3 =
0.260 71 (T/2.726 K)4 eV/cm3
|
| cosmic
background number density |
ngamma
|
410.89 (T/2.726
K)3 cm-3 |
| cosmic
background temperature |
T0
|
2.726 +- 0.005 K |
| critical
density of Universe |
rhoc
|
2.775 366 27 x 1011
h02 MS
Mpc-3 =
1.878 82(24) x 10-29 h02
g/cm3 =
1.053 94(13) x 10-5 h02
GeV/cm3 |
| day, mean
sidereal |
dsidereal
|
23h 56m
04s.090 53 |
| deuteron (2H)
mass |
md
|
1875.613 39(57) MeV/c2 |
| Earth mass
|
ME
|
5.973 70(76) x 1024
kg |
| Earth radius
(equatorial) |
RE
|
6.378 140 x 106
m |
| electron
charge magnitude |
e
|
1.602 177 33(49) x 10-19
C =
4.803 206 8(15) x 10-10 esu |
| electron mass
|
me
|
0.510 999 06(15) MeV/c2
=
9.109 389 7(54) x 10-31 kg |
| electron
radius, classical |
re
|
2.817 940 92(38) x 10-15
m |
| electron
Compton wavelength |
lambdabare
|
3.861 593 23(35) x 10-13
m |
| entropy
density/Boltzmann constant |
s/k
|
2.892 4 (T/2.726
K)3 cm-3 |
| fine structure
constant |
alpha
|
1/137.035 989 5(61) |
| gravitational
constant |
GN
|
6.672 59(85) x 10-11
m3/(kg s2) =
6.707 11(86) x 10-39 h c/(GeV/c2)2 |
| Hubble
constant |
H0
|
100 h0
km/(s Mpc) =
h0/9.778 13 Gy |
| Hubble
constant, normalized |
h0
|
0.5 < h0
< 0.85 |
| jansky
|
Jy |
10-26 W/(m2
Hz) |
| light year
(deprecated) |
ly |
0.306 6... pc =
0.946 1... x 1016 m |
| Naperian
(natural) logarithm base |
e
|
2.718 281 828 459 045
235 |
| nuclear
magneton |
muN
|
3.152 451 66(28) x 10-14
MeV/T |
| parsec (au/arcsec)
|
pc |
3.085 677 580 7(4) x
1016 m =
3.262... ly |
| permeability
of free space |
mu0
|
4 pi x 10-7
N/A2 =
12.566 370 614... x 10-7 N/A2 |
| permittivity
of free space |
epsilon0
|
8.854 187 817... x 10-12
F/m |
| pi
|
pi
|
3.141 592 653 589 793
238 |
| Planck
constant |
h
|
6.626 075 5(40) x 10-34
J s |
| Planck
constant, reduced |
hbar
|
1.054 572 66(63) x 10-34
J s =
6.582 122 0(20) x 10-22 MeV s |
| Planck mass
|
mP
|
1.221 047(79) x 1019
GeV/c2 =
2.176 71(14) x 10-8 kg |
| proton (1H)
mass |
mp
|
938.272 31(28) MeV/c2
=
1.672 623 1(10) x 10-27 kg =
1.007 276 470(12) u =
1836.152 701(37) me |
| Rydberg energy
|
h c Roo
|
13.605 698 1(40) eV |
| Schwarzschild
radius of Sun |
2 GN MS/c2
|
2.953 250 08 km |
| speed of light
in vacuum |
c
|
299 792 458 m/s |
| Stefan-Boltzmann
constant |
sigma
|
5.670 51(19) x 10-8
W/(m2 K4) |
| strong
coupling constant |
alphas
|
0.118(3) |
| Sun distance
from Core |
Ro
|
8.0(5) kpc |
| Sun luminosity
|
LS
|
3.846 x 1026
W |
| Sun mass
|
MS
|
1.988 92(25) x 1030
kg |
| Sun radius
(equatorial) |
RS
|
6.96 x 108
m |
| Sun speed
around Core |
Thetao
|
220(20) km/s |
| Sun speed to
cosmic background |
|
369.5 +- 3.0 km/s |
| Thompson cross
section |
sigmaT
|
0.665 246 16(18) barn |
| W+-
boson mass |
mW
|
80.33(15) GeV/c2 |
| Wien
displacement law constant |
b
|
2.897 756(24) x 19) x
10-3 m K |
| year, sidereal
(fixed star to fixed star, 1994) |
ysidereal
|
31 558 149.8 s |
| year, tropical
(equinox to equinox, 1994) |
y |
31 556 925.2 s |
| Z0
boson mass |
mZ
|
91.187(7) GeV/c2 |
|
OILFIELD UNITS CONVERSION TABLE |
|
OILFIELD UNITS CONVERSION TABLE |
|
Original Unit
|
Multiplied
By |
Conversion
Factor |
Equals
|
Final Unit
|
|
A |
|
acres
|
x
|
0.404 69
|
=
|
hectares
|
|
acres
|
x
|
43,560
|
=
|
square feet (ft2) |
|
acres
|
x
|
4,046.873
|
=
|
square meters (m2) |
|
acre-feet
|
x
|
43,560
|
=
|
cubic feet (ft3
or cf) |
|
acre-feet
|
x
|
7,758
|
=
|
barrels
|
|
angstrom units |
x
|
1.0E-10
|
=
|
meters (m) |
|
atmospheres
|
x
|
14.70
|
=
|
pounds/square
inch |
|
atmospheres
|
x
|
1.033
|
=
|
kilograms/square
centimeter |
|
atmospheres
|
x
|
1.013250E+05
|
=
|
pascal
|
|
atmospheres
|
x
|
33.90
|
=
|
Feet of water |
|
atmospheres
|
x
|
76.0
|
=
|
centimeter of
mercury |
|
B |
|
barrels (crude
oil) |
x
|
5.6146
|
=
|
cubic feet of
crude oil |
|
barrels (crude
oil) |
x
|
0.158 987 3 |
=
|
cubic meters of
crude oil |
|
barrels (crude
oil) |
x
|
42
|
=
|
US gallons of
crude oil, US |
|
barrels (crude
oil) |
x
|
158.987 3
|
=
|
liters of crude
oil |
|
barrels (crude
oil) |
x
|
0.136
|
=
|
metric tons of
crude oil |
|
barrels/day
|
x
|
0.0292
|
=
|
Gallons(US)/minute
|
|
barrels/day
|
x
|
1.84
|
=
|
cubic
centimeters/second |
|
barrels (crude
oil) |
x
|
0.15
|
=
|
short tons of
crude oil |
|
barrels, US
liquid |
x
|
0.75
|
=
|
barrels of crude
oil |
|
barrels, US
liquid |
x
|
31.5
|
=
|
gallons, US |
|
bars
|
x
|
0.98
|
=
|
atmospheres
|
|
bars
|
x
|
14.50
|
=
|
pounds/square
inch |
|
British thermal
units (Btu) |
x
|
3.931E-04
|
=
|
horsepower-hours
|
|
British thermal
units (Btu) |
x
|
0.000 292 8 |
=
|
kilowatthours
(kWh) |
|
bushels, US |
x
|
0.035 239 07 |
=
|
cubic meters (m3) |
|
C |
|
calories (cal) |
x
|
4.186 8
|
=
|
joules (J) |
|
centimeters (cm) |
x
|
0.394
|
=
|
inches (in) |
|
centimeters of
mercury |
x
|
0.44
|
=
|
feet of water |
|
centimeters/second |
x
|
0.036
|
=
|
kilometers/hour
|
|
centipoise
|
x
|
0.01
|
=
|
poise
|
|
centipoise
|
x
|
0.01
|
=
|
grams/cm-sec
|
|
centipoise
|
x
|
0.0010
|
=
|
pascal-second
|
|
centipoise
|
x
|
6.72E-04
|
=
|
pounds/ft-sec
|
|
cubic
centimeters (cm3) |
x
|
3.531E-05
|
=
|
cubic feet (ft3
or cf) |
|
cubic
centimeters (cm3) |
x
|
0.06102
|
=
|
cubic inches (in3) |
|
cubic
centimeters (cm3) |
x
|
2.642E-04
|
=
|
gallons, US
liquid |
|
cubic
centimeters (cm3) |
x
|
1.0E-03
|
=
|
liters (L) |
|
cubic feet (ft3
or cf) |
x
|
28,320
|
=
|
cubic
centimeters (cm3) |
|
cubic feet (ft3
or cf) |
x
|
1728
|
=
|
cubic inches (in3) |
|
cubic feet (ft3
or cf) |
x
|
7.48
|
=
|
gallons, US
liquid |
|
cubic feet (ft3
or cf) |
x
|
28.316 8
|
=
|
liters (L) |
|
cubic feet (ft3
or cf) |
x
|
2.831685E-02
|
=
|
cubic meters |
|
cubic
feet/minute |
x
|
472
|
=
|
cubic
centimeters/second |
|
cubic
feet/minute |
x
|
4.72E-4
|
=
|
cubic
meters/second |
|
cubic
feet/minute |
x
|
0.12
|
=
|
gallons/second
|
|
cubic
feet/minute |
x
|
0.471 947 4 |
=
|
liters/second
|
|
cubic inches (in3) |
x
|
16.38706
|
=
|
cubic
centimeters (cm3) |
|
cubic inches (in3) |
x
|
1.639E-05
|
=
|
cubic meters (m3) |
|
cubic inches (in3) |
x
|
4.329E-03
|
=
|
gallons (gal) |
|
cubic inches (in3) |
x
|
0.016387 06 |
=
|
liters (L) |
|
cubic meters (m3) |
x
|
35.315
|
=
|
cubic feet (ft3
or cf) |
|
cubic meters (m3) |
x
|
264.20
|
=
|
gallons, US
liquid |
|
cubic meters (m3) |
x
|
1,000
|
=
|
liters (L) |
|
cubic meters/sec
(m3/s) |
x
|
15,850
|
=
|
gallons/minute
|
|
cubic meters/sec
(m3/s) |
x
|
2118
|
=
|
cubic
feet/minute |
|
cubic meters/sec
(m3/s) |
x
|
60,000
|
=
|
liters/minute
|
|
cycles/second
|
x
|
1.0
|
=
|
hertz
|
|
D |
|
darcy
|
x
|
0.9869E-12
|
=
|
meter squared |
|
days (mean
solar) |
x
|
86,400
|
=
|
seconds
|
|
degrees (angle) |
x
|
0.0111
|
=
|
quadrants
|
|
degrees (angle) |
x
|
0.017 453 29 |
=
|
radians
|
|
degrees (angle) |
x
|
3,600
|
=
|
seconds
|
|
degrees/second
|
x
|
0.16667
|
=
|
revolutions/minute |
|
dynes
|
x
|
1.0E-05
|
=
|
joules/meter (newtons) |
|
dynes/square
centimeter |
x
|
1.0E-06
|
=
|
bars
|
|
E |
|
em (pica)
|
x
|
0.42
|
=
|
centimeters (cm) |
|
ergs
|
x
|
1.0E-07
|
=
|
joules (J) |
|
ergs
|
x
|
2.78E-14
|
=
|
kilowatthours
(kWh) |
|
ergs/second
|
x
|
1.3E-10
|
=
|
horsepower (hp) |
|
ergs/second
|
x
|
1.0E-10
|
=
|
kilowatts
|
|
F |
|
feet (ft)
|
x
|
30.48
|
=
|
centimeters (cm) |
|
feet (ft)
|
x
|
12
|
=
|
inches (in) |
|
feet (ft)
|
x
|
0.3048
|
=
|
meters (m) |
|
feet (ft)
|
x
|
1.645E-04
|
=
|
miles (nautical) |
|
feet (ft)
|
x
|
1.894E-04
|
=
|
miles (statute) |
|
feet of water |
x
|
0.029499
|
=
|
atmospheres of
water |
|
feet of water |
x
|
0.8826
|
=
|
inches of
mercury |
|
feet of water |
x
|
0.433515
|
=
|
pounds/square
inch |
|
feet/minute
|
x
|
0.5080
|
=
|
centimeter/second |
|
feet/second
|
x
|
1.09728
|
=
|
kilometers/hour
|
|
feet/second
|
x
|
0.59248
|
=
|
knots
|
|
feet/second
|
x
|
0.681818
|
=
|
miles/hour
|
|
foot-candles
|
x
|
10.763 91
|
=
|
lumens/square
meter |
|
foot-pounds
|
x
|
3.77E-07
|
=
|
kilowatthours
(kWh) |
|
foot-pounds/minute |
x
|
2.26E-05
|
=
|
kilowatts (kW) |
|
foot-pounds/sec
|
x
|
0.00181
|
=
|
horsepower
|
|
G |
|
gallons, US
(gal) |
x
|
0.031 75
|
=
|
barrels
|
|
gallons, US
(gal) |
x
|
0.02381
|
=
|
barrels of crude
oil |
|
gallons, US
(gal) |
x
|
3,785.41
|
=
|
cubic
centimeters (cm3) |
|
gallons, US
(gal) |
x
|
0.1337
|
=
|
cubic feet (ft3
or cf) |
|
gallons, US
(gal) |
x
|
3.785412E-03
|
=
|
cubic meters (m3) |
|
gallons, US
(gal) |
x
|
0.832675
|
=
|
gallons,
imperial |
|
gallons, US
(gal) |
x
|
3.785412
|
=
|
liters (L) |
|
gallons, liquid
British imperial |
x
|
1.2014
|
=
|
gallons, US
liquid |
|
gallons of crude
oil |
x
|
0.02380952
|
=
|
barrels of crude
oil |
|
gallons/minute,
US |
x
|
8.0208
|
=
|
cubic feet/hour |
|
gallons/minute,
US |
x
|
0.134
|
=
|
cubic
feet/minute |
|
gallons/minute,
US |
x
|
6.309E-05
|
=
|
cubic meters/sec |
|
gausses
|
x
|
1.0E-04
|
=
|
webers/square
meter |
|
grains
|
x
|
0.064798 91 |
=
|
grams (g)
|
|
grams (g)
|
x
|
0.0353
|
=
|
ounces
|
|
grams (g)
|
x
|
2.204623E-03
|
=
|
pounds (lb) |
|
grams/centimeter
|
x
|
5.6E-03
|
=
|
pounds/inch
|
|
grams/cubic
centimeter |
x
|
62.43
|
=
|
pounds/cubic
foot |
|
grams/cubic
centimeter |
x
|
8.347
|
=
|
pounds/gallon
|
|
grams/liter
|
x
|
1,000
|
=
|
parts/million
|
|
grams/liter
|
x
|
8.34
|
=
|
pounds/1,000
gallons |
|
grams/liter
|
x
|
0.06243
|
=
|
pounds/cubic
foot |
|
grams/square
centimeter |
x
|
2.04816
|
=
|
pounds/square
foot |
|
gram-calories
|
x
|
1.56E-06
|
=
|
horsepower-hours
|
|
gram-calories
|
x
|
1.16E-06
|
=
|
kilowatthours
(kWh) |
|
H |
| hectares (ha) |
x |
2.471
|
= |
acres
|
| hectares (ha) |
x |
107,600
|
= |
square feet (ft2) |
| hectares (ha) |
x |
10,000
|
= |
square meters (m2) |
| horsepower (hp) |
x |
1.014
|
= |
horsepower (metric)
|
| horsepower (hp) |
x |
42.44
|
= |
British thermal units/minute |
| horsepower (hp) |
x |
550
|
= |
foot-pounds/second
|
| horsepower-hour (hp-hr) |
x |
2.684520E+6
|
= |
Joules
|
| horsepower (hp) |
x |
0.746043
|
= |
kilowatts
|
| horsepower (metric) |
x |
0.986
|
= |
horsepower
|
| horsepower (metric) |
x |
542.5
|
= |
foot-pounds/second
|
|
I |
|
inches (in) |
x
|
2.54
|
=
|
centimeters (cm) |
|
inches (in) |
x
|
0.0254
|
=
|
meters (m) |
|
inches (in) |
x
|
1.578E-05
|
=
|
miles (mi) |
|
inches of
mercury |
x
|
0.4912
|
=
|
pounds/square
inch |
|
inches of water
at (4oC) |
x
|
2.458E-03
|
=
|
atmospheres
|
|
inches of water
at (4oC) |
x
|
0.03
|
=
|
pounds/square
inch |
|
J |
|
joules (J) |
x
|
9.48E-04
|
=
|
British thermal
units (Btu) |
|
joules (J) |
x
|
2.778E-04
|
=
|
watthours (Wh) |
|
K |
|
kilograms (kg) |
x
|
2.204 6
|
=
|
pounds (lb) |
|
kilograms (kg) |
x
|
9.84E-04
|
=
|
tons, long |
|
kilograms (kg) |
x
|
1.1E-03
|
=
|
tons, metric (t) |
|
kilograms/sqhare
meter |
x
|
1.42E-03
|
=
|
pounds/square
inch |
|
kilograms/meter
|
x
|
0.67197
|
=
|
pounds/foot
|
|
kilograms/square
centimeter |
x
|
0.9678
|
=
|
atmospheres
|
|
kilograms/square
centimeter |
x
|
14.223
|
=
|
pounds/square
inch |
|
kilograms/square
meter |
x
|
9.81E-05
|
=
|
bars
|
|
kilogram-meters
|
x
|
2.72E-06
|
=
|
kilowatthours
(kWh) |
|
kilometers (km) |
x
|
3,280.84
|
=
|
feet (ft)
|
|
kilometers (km) |
x
|
0.621 4
|
=
|
miles (mi) |
|
kilometers/hour
|
x
|
0.91134
|
=
|
feet/second
|
|
kilometers/hour
|
x
|
0.53995
|
=
|
knots
|
|
kilometers/hour
|
x
|
0.62137
|
=
|
miles/hour
|
|
kilowatts (kW) |
x
|
1.341
|
=
|
horsepower (hp) |
|
kilowatts (kW) |
x
|
1,000
|
=
|
watts (W)
|
|
kilowatthours
(kWh) |
x
|
3,413
|
=
|
British thermal
units (Btu) |
|
kilowatthours
(kWh) |
x
|
3.60E+06
|
=
|
Joules |
|
L |
|
liters (L) |
x |
0.0063
|
= |
barrels of oil |
|
liters (L) |
x |
0.0084
|
= |
barrels
|
|
liters (L) |
x |
0.035315
|
= |
cubic feet (ft3
or cf) |
|
liters (L) |
x |
61.02
|
= |
cubic inches (in3) |
|
liters (L) |
x |
0.264
|
= |
gallons
|
|
long tons
|
x |
1,016.047
|
= |
kilograms (kg) |
|
long tons
|
x |
1.016047
|
= |
metric tons (t) |
|
long tons
|
x |
2,240
|
= |
pounds (lb) |
|
long tons
|
x |
1.12 |
= |
short tons (st) |
|
M |
|
meters (m) |
x
|
3.281
|
=
|
feet (ft)
|
|
meters (m) |
x
|
6.21E-04
|
=
|
miles (statute) |
|
meters/second
|
x
|
2.23
|
=
|
miles/hour
|
|
meters/second
|
x
|
196.8
|
=
|
feet/minute
|
|
metric tons (t) |
x
|
1,000
|
=
|
kilograms (kg) |
|
metric tons (t) |
x
|
2,204.62
|
=
|
pounds (lb) |
|
metric tons (t) |
x
|
1.1023
|
=
|
short tons (st) |
|
metric tons of
crude oil |
x
|
7.33
|
=
|
barrels (bbl) |
|
microns
|
x
|
1.0E-06
|
=
|
meters (m) |
|
miles, statute |
x
|
161,000
|
=
|
centimeters (cm) |
|
miles, statute |
x
|
5,280
|
=
|
feet (ft)
|
|
miles, statute |
x
|
1.609344
|
=
|
kilometers (km) |
|
miles, statute |
x
|
1,609
|
=
|
meters (m) |
|
miles, statute |
x
|
0.868975
|
=
|
miles, nautical |
|
miles/hour
|
x
|
44.70
|
=
|
centimeter/second |
|
miles/hour
|
x
|
1.4667
|
=
|
feet/second
|
|
meters (m) |
x
|
3.281
|
=
|
feet
|
|
meters (m) |
x
|
6.21E-04
|
=
|
miles (statute) |
|
millimeters
|
x
|
0.03937
|
=
|
inches
|
|
milligrams/liter
|
x
|
1
|
=
|
parts/million
|
|
million
gallons/day |
x
|
1.5472
|
=
|
cubic
feet/second |
|
minutes (angles) |
x
|
0.0167
|
=
|
degrees
|
|
N |
|
newtons
|
x
|
0.22481
|
=
|
pounds force
|
|
newtons
|
x
|
100,000
|
=
|
dynes |
|
O |
|
ounces (oz) |
x
|
28.34
|
=
|
grams (g)
|
|
ounces (oz) |
x
|
0.0625
|
=
|
pounds (lb) |
|
P |
|
pascal
|
x
|
1
|
=
|
newton/sq meter |
|
pascal
|
x
|
9.871E-06
|
=
|
atmosphere
|
|
parts/million
|
x
|
8.34
|
=
|
pounds/million
gallon (gal) |
|
pints, US liquid |
x
|
0.125
|
=
|
gallons, US
(gal) |
|
poise (P)
|
x
|
1
|
=
|
grams/centimeter
second |
|
poundals
|
x
|
13,826
|
=
|
dynes
|
|
pounds (lb) |
x
|
4.45E+05
|
=
|
dynes
|
|
pounds (lb) |
x
|
453.59
|
=
|
grams (g)
|
|
pounds (lb) |
x
|
4.5359E-04
|
=
|
Tons (metric) |
|
pounds (lb) |
x
|
4.448
|
=
|
joules/meter (newtons) |
|
pounds (lb) |
x
|
0.45359237
|
=
|
kilograms (kg) |
|
pounds (lb) |
x
|
16
|
=
|
ounces (oz) |
|
pounds of water |
x
|
27.68
|
=
|
cubic inches (in3) |
|
pounds of water |
x
|
0.11983
|
=
|
gallons (gal) |
|
pounds/cubic
foot |
x
|
0.1337
|
=
|
pounds/gallon
(US) |
|
pounds/cubic
foot |
x
|
0.006944
|
=
|
pounds/sq
inch/foot (psi/ft) |
|
pounds/cubic
foot |
x
|
0.016026
|
=
|
specific gravity |
|
pounds/cubic
foot |
x
|
0.016026
|
=
|
grams/cubic
centimeter |
|
pounds/cubic
foot |
x
|
16.026
|
=
|
kilograms/cubic
meter |
|
pounds/cubic
inch |
x
|
27.68
|
=
|
grams/cubic
centimeter |
|
pounds/cubic
inch |
x
|
27,680
|
=
|
kilograms/cubic
meter |
|
pounds/foot
|
x
|
1.4882
|
=
|
kilograms/meter
|
|
pounds/inch
|
x
|
178.60
|
=
|
grams/centimeter
|
|
pounds/gallon (ppg) |
x
|
0.12005
|
=
|
specific gravity |
|
pounds/gallon (ppg) |
x
|
0.052
|
=
|
pounds/sq
inch/foot (psi/ft) |
|
pounds/gallon (ppg) |
x
|
7.48
|
=
|
pounds/cubic
foot |
|
pounds/gallon (ppg) |
x
|
0.1198
|
=
|
grams/cubic
centimeter |
|
pounds/square
inch |
x
|
0.0680
|
=
|
atmospheres
|
|
pounds/square
inch |
x
|
2.3095
|
=
|
feet of water |
|
pounds/square
inch |
x
|
2.03602
|
=
|
inches of
mercury |
|
pounds/square
inch |
x
|
703.0696
|
=
|
kilograms/square
meter |
|
pounds/square
inch |
x
|
6.894757E+03
|
=
|
pascal
|
|
pounds/square
inch |
x
|
144
|
=
|
pounds/square
foot |
|
pounds/sq inch/foot(psi/ft)
|
x
|
19.23
|
=
|
pounds/gallon
(US) |
|
pounds/sq inch/foot(psi/ft)
|
x
|
144
|
=
|
pounds/cubic
foot |
|
pounds/sq
inch/foot (psi/ft) |
x
|
2.3095
|
=
|
specific gravity |
|
Q |
|
quadrants, angle |
x
|
90
|
=
|
degrees
|
|
quadrants, angle |
x
|
1.5708
|
=
|
radians
|
|
quarts, liquid |
x
|
57.75
|
=
|
cubic inches (in3) |
|
quarts, liquid |
x
|
9.46E-04
|
=
|
cubic meters (m3) |
|
R |
|
radians
|
x
|
57.29
|
=
|
degrees
|
|
radians
|
x
|
3,438
|
=
|
minutes
|
|
radians
|
x
|
206,000
|
=
|
seconds
|
|
revolutions
|
x
|
360
|
=
|
degrees
|
|
revolutions
|
x
|
4
|
=
|
quadrants
|
|
revolutions
|
x
|
6.283185
|
=
|
radians
|
|
S |
|
seconds (angle) |
x
|
2.78E-04
|
=
|
degrees
|
|
seconds (angle) |
x
|
4.848137E-06
|
=
|
radians
|
|
short tons (st) |
x
|
0.8929
|
=
|
long tons
|
|
short tons (st) |
x
|
0.9071847
|
=
|
metric tons (t) |
|
short tons (st) |
x
|
2,000
|
=
|
pounds (lb) |
|
short tons of
crude oil |
x
|
6.65
|
=
|
barrels (bbl) |
|
specific gravity |
x
|
1
|
=
|
grams/cubic
centimeter |
|
specific gravity |
x
|
0.433
|
=
|
pounds/sq
inch/foot (psi/ft) |
|
specific gravity |
x
|
8.33
|
=
|
pounds/gallon
(US) |
|
specific gravity |
x
|
350.5
|
=
|
pounds/barrel
|
|
specific gravity |
x
|
62.4
|
=
|
pounds/cubic
foot |
|
square
centimeters (cm2) |
x
|
1.08E-03
|
=
|
square feet (ft2) |
|
square
centimeters (cm2) |
x
|
0.1550
|
=
|
square inches
(in2) |
|
square inch (in2) |
x
|
6.4516
|
=
|
square
centimeter |
|
square feet (ft2) |
x
|
2.2956E-05
|
=
|
acres
|
|
square feet (ft2) |
x
|
929.03
|
=
|
square
centimeters (cm2) |
|
square feet (ft2) |
x
|
144
|
=
|
square inches
(in2) |
|
square feet (ft2) |
x
|
0.09290304
|
=
|
square meters (m2) |
|
square feet (ft2) |
x
|
3.59E-08
|
=
|
square miles (mi2) |
|
square
kilometers (km2) |
x
|
247.10
|
=
|
acres
|
|
square
kilometers (km2) |
x
|
100
|
=
|
hectares
|
|
square
kilometers (km2) |
x
|
0.386
|
=
|
square miles (mi2) |
|
square meters (m2) |
x
|
2.471E-04
|
=
|
acres
|
|
square meters (m2) |
x
|
10.763915
|
=
|
square feet (ft2) |
|
square meters (m2) |
x
|
3.86E-07
|
=
|
square miles (mi2) |
|
square miles (mi2) |
x
|
640
|
=
|
acres
|
|
square miles (mi2) |
x
|
27,900,000
|
=
|
square feet (ft2) |
|
square miles (mi2) |
x
|
2.589988
|
=
|
square
kilometers (km2) |
|
T |
|
therms
|
x
|
100,000
|
=
|
BTUs of natural
gas |
|
therms
|
x
|
1.054804E+08
|
=
|
joules (J) |
|
tonnes
|
x
|
1.0
|
=
|
tons, metric
|
|
tons, long |
x
|
1,016.047
|
=
|
kilograms (kg) |
|
tons, long |
x
|
1.016047
|
=
|
metric tons (t) |
|
tons, long |
x
|
2,240
|
=
|
pounds (lb) |
|
tons, long |
x
|
1.12
|
=
|
short tons (st) |
|
tons, metric (t) |
x
|
7.33
|
=
|
barrels of crude
oil |
|
tons, metric (t) |
x
|
1,000
|
=
|
kilograms (kg) |
|
tons, metric (t) |
x
|
2,204.62
|
=
|
pounds (lb)
|
|
tons, short (st) |
x
|
6.65
|
=
|
barrels of crude
oil |
|
tons, short (st) |
x
|
0.8929
|
=
|
long tons
|
|
tons, short (st) |
x
|
0.9071847
|
=
|
metric tons (t) |
|
tons, short (st) |
x
|
2,000
|
=
|
pounds (lb) |
|
W |
|
watts (W)
|
x
|
3.41219
|
=
|
British thermal
units/hour |
|
watts (W)
|
x
|
0.001341
|
=
|
horsepower (hp) |
|
watts (absolute) |
x
|
1
|
=
|
joules/second
|
|
watthours (Wh) |
x
|
3.41219
|
=
|
British thermal
units (Btu) |
|
watthours (Wh) |
x
|
2,656
|
=
|
foot-pounds
|
|
weeks
|
x
|
168
|
=
|
hours
|
|
Y |
|
years (mean of
4-year period) |
x
|
365.25
|
=
|
days
|
|
years (mean of
4-year period) |
x
|
8,766
|
=
|
hours
|
|
years (mean of
4-year period) |
x
|
526,000
|
=
|
minutes (time) |
|
years (mean of
4-year period) |
x
|
31,558,150
|
=
|
seconds (time) |
|
years (mean of
4-year period) |
x
|
52.17
|
=
|
week
|
|
|
