40
VNG/VLP SERIES PRESSURE WASHER
OPERATOR’S MANUAL
BASED ON 60
o
F
PROPANE
BUTANE
Formula
C3H8
C4H10
Vaporization Point (
o
F)
-43.7
31.1
Specific Gravity (Vapor)
1.522
2.006
Specific Gravity (Liquid)
0.508
0.584
Lbs. Per Gallon (Liquid)
4.23
4.87
B.T.U. Per Cubic Foot (Vapor)
2.563
3.39
B.T.U. Per Lb. (Vapor)
21.663
21/3-9
B.T.U. Per Gallon (Liquid)
91.74
1-3/93
Cubic Feet Per Lb. (Liquid)
8.607
7/53
Cubic Feet Per Gallon (Liquid)
3.45
31/9
Octane Number
125
1
Molecular Weight
44.09
58.12
To calculate running cost:
1 cubic Ft./1,000 B.T.U.
100 cubic Ft./Therm
Therm/Hour
50¢ Therm
Example:
Using natural gas
400,000 BTU Machine
400 cubic feet
4 Therms/hour
4 x .50 = $2.00/hour to run
BASIC FACTS
PRESSURE EQUIVALENTS
Simply stated, pressure is the force exerted by a gas or liquid attempting to escape from a container. It is useful to
know how strong this "attempt to escape" is. Pressure can be measured with a manometer or with a pressure gauge.
At the lower levels, it is expressed in "inches of water column" i.e. 1" w.c. Higher pressures are expressed in terms of
the force exerted against a square inch of area. For example, 125 lbs. per square inch (125 psi).
1" Water Column
=
50 Oz./Sq. In.
11" Water Column
=
6.35 Oz./Sq. In.
11" Water Column
=
4 Lb./Sq. In.
1 Lb./Sq. In.
=
27.71" Water Column
1 Lb./Sq. In.
=
2.04" Mercury
1" Mercury
=
.39 Lb./Sq. In.
1 Std. Atmosphere
=
14.73 Lbs./Sq. in
