Engineering Specifications (Rough Draft)
List of Metrics
Corresponding Metric
Importance
Marginal
Ideal Value
Need
(1 to 10)
Value
Rakes need to
Speed of the 8
10 - 17
12 - 15
turn at specific rakes
Units
m/min
speed as not to
suspend the
solid matter
Torque of the
torque tube
should not
exceed the
maximum
torque
Torque tube
must
withstand a
lateral load at
bottom end
Torsional
force on
tube
7
55 - 65
60
% of
Maximum
Torque
Force of the
load
7
4.0 – 5.0
4.5
kN
The blades
must
accommodate
a certain
sediment
depth
Structures
should have a
relatively long
design life.
Maximum
torque is high
enough for
the torque
system
Depth of
blades
6
190- 210
200
mm
Estimated
design life of
structures
6
8 – 10+
10+
years
Maximum
6
torque of the
system (Tmax)
135 – 261
260
kN
Design life of
drive system
must be equal
or more than
that of other
structural
components
Estimated
design life of
drive system
6
8 – 10+
10+
years
Maintenance
should be
Total
maintenance
5
4-6
5
Days/month
minimum on
the structure
Drive system
must be as
efficient as
possible
days per
month
Calculated
using power
input and
shaft output
Drive System Specifications
6
75
80
%
Mounting Frame
4
4
Number of
locations
110
kg
30
kg
Must be
attached
firmly to the
bridge
Total amount 6
of locations
where bridge
is mounted
Must be able
to support the
weight of the
drive system
and torque
tube attached
to it
Weight of
the drive
system and
torque tube
8
100
Torque tube
20 - 30
Must be able
to support the
weight of the
rakes
Weight of
the rakes
7
Must transfer
rotating
motion to the
rakes
Torque
transferred
to the shaft
7
500
550
Nm
Must be
unsupported
at the bottom
-
6
-
-
Yes or No
Rakes
Enough rakes
needed
Number of
rakes
6
4
4
Total
Blades of
rakes must be
Angle of the
blades
5
40 - 50
45
degrees
at a specific
angle