NPK C2D - Productivity

NPK
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PRODUCTIVITY
It is difficult to accurately predict the productivity of a boom mounted compactor for a
particular application. There are many variables to consider - type of material, lift
thickness, compaction specification requirement, machine weight, number of passes
required and operator skill.
One method to estimate the approximate productivity is to apply the following formula.
This formula is a rough assessment of the volume of material a boom mounted
compactor can compact in an hour:
METRIC
U.S. UNITS
A x L x C x E
A x L x C x E
cubic meters/hr =
cubic yards/hr =
T x P x M
T x P x M
A =
sq. meter, compaction area of
baseplate
A =
sq. feet, compaction area of
baseplate
L =
meter, compacted lift depth
L =
feet, compacted lift depth
C =
3600, conversion factor for time
and volume
C =
133.2, conversion factor for time
and volume
E =
time efficiency (0.75 for a 45
minute hour, 0.83 for 50 minute
hour)
E =
time efficiency (0.75 for a 45
minute hour, 0.83 for 50 minute
hour)
T =
30 seconds for average
conditions, time to compact a
surface area equal to the
baseplate area (includes overlap
and repositioning)
T =
30 seconds for average
conditions, time to compact a
surface area equal to the
baseplate area (includes overlap
and repositioning)
P =
number of passes required
P =
number of passes required
M =
0.7, multiple pass constant (use
1.0 for single pass, shallow trench
calculation
M =
0.7 multiple pass constant (use
1.0 for single pass, shallow trench
calculation)
Example:
NPK C6C Compactor, using two passes
for trench backfill compaction.
A = 0.75 sq. meter T = 30 sec
L = 1.2 meter E = 0.75
0.75 x 1.2 x 3600 x 0.75
cubic meters/hr = 30 x 2 x 0.7
= 58 cubic meters/hr
Example:
NPK C6C Compactor, using two passes
for trench backfill compaction.
A = 8.1 sq. feet T = 30 sec
L = 4 feet E = 0.75
8.1 x 4 x 133.2 x 0.75
cubic yards/hr = 30 x 2 x 0.7
= 77 cubic yards/hr
The above formula does not guarantee productivity. Results will vary depending
on operator, carrier and job conditions.