Karcher IV 100 - 55 M B1 - Manual (Page 20)

20 English 5.906-587.0 Rev. 00 (05/14)
Recalculation of the volume flow per vacuuming point.
Example:
IV 100/55 as per technical data sheet with a pressure loss
of 128 mbar = ~330 m³/h.
With 2 vacuuming points the following applies:
Volume flow per vacuuming point:
330m³/h / 2 vacuuming points = 165 m³/h per vacuuming
point.
Calculation of the actual flow velocities in the sections and
subsequent alignment with the required air speed of the
application, in the example 20-23 m/s.
Example:
In the sections 1 and 2 the required air speed of the exam-
ple cannot be reached. Thus, a more powerful vacuum
cleaner must be used.
Note
In this example a reduction of the pipe diameter would in-
crease the flow velocities in the relevant sections, howev-
er, it would also reduce the dissipation power and thus the
achievable volume flow.
The recalculation takes place analogously to the previous
example.
Step 1
The total volume flow of all simultaneously operated vacu-
uming points is calculated for the calculation of the air
speed first.
Example:
IV 100/75 as per technical data sheet 153l/s, that equals
550 m³/h according to the calculation tool.
With 2 vacuuming points the following applies:
Volume flow per vacuuming point:
550m³/h / 2 vacuuming points = 275 m³/h per vacuuming
point.
Available volume flow per vacuuming point = 275 m³/h
Step 2
Now the maximum pipe diameter is calculated under con-
sideration of the flow velocities.
Example:
As per the table in Chapter "Air speed" plastic granules Ø
2-3 mm require a air speed of 20-23 m/s. By means of the
calculation tool a max. pipe diameter of 91 mm is calculat-
ed for section 1 from a volume flow of 550 m³/h and the
speed of 23 m/s. In due consideration of the air speed the
next smaller diameter is chosen from the pipeline pro-
gramme. In the example DN 80.
Step 3
Calculation of the flow velocities in the individual sections
of the main run by means of the calculation tool.
Example:
11.7 Step 7
11.8 Step 8
Sec-
tion Suction
hose Volume
flow rate Flow speed
1 DN 80 330m³/h 18.24m/s
2 DN 60 165m³/h 16.21 m/s
3 DN 50 165m³/h 23.34 m/s
11.9 Step 9
Sec-
tion Suction
hose Volume
flow rate Flow speed
1 DN 80 500 m³/h 30.39 m/s
2 DN 60 275 m³/h 27.02 m/s
3 DN 50 275 m³/h 38.90 m/s