Schwing SP 750-18 - Using a Nomograph

134
Appendix
SP 500 / 750-15 / 750-18 / 1000 / 1250 Operation Manual
Using a Nomograph
Concrete pumps are limited in what jobs they can do by
three factors:
1. the amount of power available,
2. the maximum concrete output available, and
3. the maximum concrete pressure available.
To estimate the power a pump requires to complete a
particular job and to determine which pump is appropri-
ate, a nomograph is used.
With a concrete pump that is driven by its own prime
mover, such as a trailer-mounted concrete pump or a
truck-mounted pump with a separate drive engine, the
power rating (in Kw) is shown for the engine or electric
motor. With a truck-mounted pump that uses a PTO
from the truck engine, the power rating reects the pow-
er output of the hydraulic pumps only. (All the power
from the truck engine is normally not available to the
concrete pump and should not be used for power calcu-
lations.) If you know the required output for the job, the
nomograph will help you calculate the required pres-
sure. If you know the output and pressure, you can cal-
culate the power requirement.
The nomograph was developed by extensive trial-and-
error testing and has proven to be accurate to ±10%
in nearly all pumping applications. The original nomo-
graphs used “spread measure” of fresh concrete in-
stead of slump, and the two are not directly interchange-
able. Some approximations are used in translating the
charts from spread measure to slump, but the ±10%
accuracy still applies. In all cases, it is assumed that
you will receive fresh, high-quality concrete on your job
and that the concrete will be plastic enough to ow into
the material cylinders. If you know that the concrete will
be hard to feed into the cylinders, you should adjust the
output requirement to compensate for incomplete lling.
For example, if you will need 50 cubic yards per hour
into the form but the concrete is so sti󰀨 that it will ll
the cylinders only 80%, you should multiply the required
output by 1.25 (1 ÷ 80%).
The nomograph is divided into four quadrants.The up-
per left quadrant is the beginning and end point of the
graph, and it shows maximum output, pressure, and
power for a specic machine. The upper right quadrant
accounts for the relationship between concrete output
and pipeline diameters. The lower right quadrant ac-
counts for the resistance to ow of the entire pipeline
system. The lower left quadrant accounts for the pump-
ability of the concrete.
100
2000
200
300
400
500
600
80010001200
1500180025003000
2"
2.5"
3"
4" 5" 6"
P in PSI
Q in yd
3
/hr.
Pipeline diameter in inches
Proportional value of pipeline in feet
For vertical placing,
add 1.105 PSI per foot
of level difference.
Slump of fresh concrete in inches
6" 5" 4.5"
4"
8701566
6003000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 400 200
200
180
160
140
120
100
80
60
40
20
67
116
Rodside
Pistonside
120/80 x 1600:200
132 KW
Pumpkit Model:
Power:
132 KW
(72600)
TK number does not apply to truck mounted units.
Curve shown is the Power Factor number (PF).
42 boom-small-no blocks-eps
Upper Left Quadrant
Lower Left Quadrant
Upper Right Quadrant
Lower Right Quadrant