Schwing SP 305, Operation Manual

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Appendix
Operation Manual - SP 305 76 revDate
The quadrants
1. The upper left quadrant describes the power
curve of a given hydraulic pump Kw rating and the
maximum output and maximum pressure of a
particular model of concrete pump (Figure 51).
Any concrete pump selected for a job must meet three
technical parameters:
• the power factor number of the pump must be
equal to or greater than the power factor num-
ber of the job,
• the maximum output required by the job must
be available from the pump, and
• the maximum pressure required by the job
must be available from the pump.
It is important to notice the pump maximum pressure
and maximum output, even if the power factor number
of the pump is larger than the job requires. These
parameters are decided during the design stage of the
unit and cannot be adjusted on the job. If the unit is
able to go from rod side to piston side, maximum
pressure and output can be exchanged—that is, you can
decrease one while increasing the other the same
amount.
The power factor number (PF) replaces the TK
number on a truck-mounted unit. It is the Kw
multiplied by a constant (550) that has several
efficiency factors figured in. When using an
Americanized nomograph (pressure in PSI and flow in
cubic yards per hour), the pressure multiplied by the
output must always be less than or equal to the PF. For
example, if you needed 50 cubic yards per hour and
determined that this will require 750 PSI, you can
multiply 50 by 750, which equals 37,500. Any pump
you select must have a PF of 37,500 or greater. If you
are using a nomograph that has been converted to
metric units of measure (pressure in bar and output in
cubic meters per hour), you can still multiply the
pressure by the output, but you must multiply the
answer by the conversion factor between metric and
English units of measure to get the PF. The conversion
factor for cubic yards to cubic meters and for bar to PSI
is 18.966. For all practical purposes, you can use 19.
For example, if you need 50 cubic meters per hour and
determine that your job setup will require 65 bar, you
can multiply 50 by 65, which equals 3250. Multiply
this by 19, and you find that your PF requirement is
61,750. Again, any pump you select for the job in this
example should have a PF of 61,750 or greater.
The maximum output (abbreviated as max Q) is
determined by the size of the hydraulic pumps, the
number of strokes per minute, and the size of the
differential and material cylinders. The unit is usually
designed so maximum output can be achieved only at
P in PSI
Q in yd
3
/hr
.
TK number does not apply to truck mounted units.
Curve shown is Power Factor number (PF).
72600
132 KW
3000 2800 2600 2400 2200 2000 1800 1600 1400 1200 1000 800 600 400 200
200
180
160
140
120
100
80
60
40
20
For vertical placing,
add 1.105 PSI per foot
of level difference.
Rod Side
Piston Side
000028.eps
Power curve
Kw rating
Power factor
number
(replaces TK)
Maximum output and
maximum pressure of
a specific unit
Figure 51
Upper left quadrant
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