6-9.
6-10.
6-11.
6-12.
6-13.
What are the characteristics of
the movement of materials within
a continuous-flow plant pugmill?
1
They are confined in the
mixer chamber
2.
They are propelled toward
discharge
3.
They are continuously mixed
in the mixer chamber
4.
They are continuously mixed,
weighed, then discharged
What period of time begins
when all the combined mineral
aggregates are in the mixer
and ends when the gate is open?
1.
The total mixing time
2.
The wet mixing time
3.
The dry mixing time
4.
The shortest mixing time
What period of time starts with
the asphalt application and ends
with the opening of the discharge
gates?
1.
The total mixing time
2.
The wet mixing time
3.
The dry mixing time
4.
The shortest mixing time
What environmental condition
makes asphalt film harden on
the aggregates?
1.
Exposure to air
2.
Exposure to moisture
3.
Exposure to heat and air
4.
Exposure to moisture and air
Which of the following is NOT
a part of the automatic control
system for a continuous-flow
plant?
1.
Burner controls
2.
Mix discharge
3.
Dryer control
4.
Mixer and gradation cutoffs
Learning Objective: Recognize
the operational processes of
a drum-mix asphalt plant.
6-14.
6-15.
6-16.
6-17.
6-18.
6-19.
In a drum-mix plant, in what
location is aggregate mixed
with the asphalt?
1.
In the mix surge silo
2.
In the hot-mix conveyer
3.
In the dust collector
4.
In the dryer
The drum-mix plant gradation
control unit proportions all
the aggregate before it enters
the mixing drum.
1.
True
2.
False
What factor is the basis for
determining the quantity of
asphalt delivered into the drum?
1.
The weight of the aggregate
2.
The gradation of the aggregate
3.
The drum-mix output
requirement
4.
The speed of the in-line belt
feeder
What section in a drum-mixer
heats and dries the aggregate?
1.
Primary
2.
Intermediate
3.
Secondary
4.
Third
What condition creates an oily
coating on the aggregate
particles?
1.
Aggregate not heated
2.
An unbalanced distribution
of asphalt
3.
A lack of balance in the
burner operation
4.
Drum-mixer speed is too slow
The drum-mix plant produces a
batch-flow of asphalt that can
be temporarily stored in the surge
silo.
1.
True
2.
False
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