Nilfisk-Advance Advance Retriever 2060, Service Manual

Page: 129 / 165

PHYSICAL PROPERTIES of GASOLINE
&
PRO
PANE
ZENITH FUEL SYSTEMS,
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PROPERTY
FORMULA
OCTANE (R + M) / 2
ENERGY DENSITY
( BTU / LB )
LOWER
HIGHER
( BTU / GAL)
LB / GAL
SPECIFIC GRAVITY
(AIR)
BOILING POINT
NATURAL STATE
STORED STATE
FLAMMABILITY LIMITS
COMBUSTION AIR
REQ’D. by WEIGHT
GASOLINE
C8 H18
(APPROX.)
82 – 93
19,000
20,360
114,000
6.2
3.5
80 – 440 (F)
LIQUID
LIQUID
1.4% - 7.6%
14.7 : 1
PROPANE
C3 H8
95 – 104
19,920
21,650
85,500
4.2
1.5
- 44 (F)
GAS
LIQUID
2.37%- 9.5%
15.5 : 1
OPERATIONAL DIFFERENCES
High carbon fuels are better conductors of
electrical energy. Thus propane demands
more electrical energy to ignite the fuel / air
mixture. Low carbon fuels have lower CO
exhaust emissions.
With Octane rating being a measure of a
fuel’s resistance to knock, propane can
stand higher compression pressures and
greater ignition timing than gasoline.
High hydrogen to carbon ratio fuels pro-
duce more heat energy per pound, where
as high carbon to hydrogen ratio fuels
have more heat energy per gallon.
Fuel mileage on propane will be less than
the mileage on gasoline.
Although a propane tank is heavier than its
gasoline counterpart, fully laden, total
weights are similar.
Both fuel vapors are heavier than air.
Above –44(F) propane becomes a vapor
In open air.
Propane, unlike gasoline, is stored under
pressure. The pressure varies with temp.
At 35 deg. (F), tank pressure is 58 PSIG; at
95 deg. (F) tank pressure will be 160 PSIG.