To compute truck application speed in feet per
minute (FPM):
To compute truck application speed in miles per hour:
To compute the length of spread in feet:
Where
L =
T =
W =
ROA =
Length of spread in feet
Total gallons in distributor
Sprayed width of roadway in feet
Rate of application in gallons per square
yard.
ASPHALT KETTLE
The asphalt kettle shown in figure 16-37 is equipped
for hand-spraying bituminous materials for dressing
stretches of road or runway shoulders, filling surface
cracks, and spray-coating areas for asphalt repairs,
surface treatment, or seal coating.
The trailer-mounted tank consists of an outer shell
with a 165-gallon capacity storage and melting tank
Figure 16-37.—Asphalt kettle.
mounted inside. A removable fuel burner, mounted
inside the kettle outer shell, provides heat to the melting
tank through a baffle. A flue stack located on the
forward end of the melting tank over the top of the baffle
and burner assembly, provides an escape for exhaust
gases. A thermometer, inserted through an insulated
pipe into the interior of the melting tank indicates the
temperature reading of the bituminous material being
heated. When the bituminous material is overheated, a
fire or explosion can result.
A two-cylinder gasoline engine provides power for
the bitumen pumping system. When you shift the clutch
shifter lever, the engine is engaged to the pump
assembly that provides the pressure for all pumping
operations.
A flexible, metal spray hose, which
connects the pump to the hand-held spray bar assembly,
is used to convey bitumen to the surface being repaired.
SAFETY PRECAUTIONS
Safety precautions for the distributor truck and
asphalt kettle operations are as follows:
. Always have dry chemical type of extinguishers
available and in good condition.
l Check all body mounting tie-downs and
fasteners. On trailer units, check kingpin plate fasteners
and all suspension and running gear components.
. Lighted cigarettes or other sources of combustion
must be kept clear of open manholes or overflow vents
to reduce fire hazards.
l Sparks from the engine exhaust can be for the
ignition of volatile gases.
. Remain clear of rotating drives when the unit is in
operation to prevent becoming entangled in the machine.
c Use goggles and gloves or insulated material
when handling the spray bar, sections, or hoses to
prevent burns.
. Monthly, check (and if necessary clean) the
3-inch overflow tube to ensure that the tube is not
clogged.
l Open a manhole slowly to relieve any pressure
that may exist in the tank.
. Check and ensure that all pipe and hose
connections are secure before operating valves to
eliminate leaks (that may spray hot bitumen on other
personnel).
l Keep the unit clean for safety and operation.
16-32
