Schwing 30100750, Руководство по эксплуатации

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Appendix
All S P Rock Valve Model s
Startup 250:Users:Danny:Desktop:Operation manuals:line
pumps:All SP Rock Valve models:Frame files:Appendix.fm
Operation Manual -
14 3
As you can see by the chart in Figure 71, we are re-
entering the upper left quadrant through the pressure
scale at about 650 PSI. Remember, we now have to add
the head pressure for our vertical rise. At 1.1 PSI per
foot of level difference, and our 250 foot vertical run,
we must now add 1.1 x 250 =
275 PSI to the 650 PSI
from the chart.
650 P S I+ 275 P S I = 925 P S I
NOTE!
W hen c a lc u l a tin g the he ad p ress u re from
v ertic a l r u ns, it d oesn’t m a tter if the
p i p eline r u ns str a i g ht up a n d d own, or if it
r u ns up hill a t a n a n g le. Only the le v el
d ifference in feet is nee d e d for the p ress u re
c a lc u l a tion. If the p i p eline is r u nnin g
d ownhill the o p er a tor will nee d s p eci a l
knowle dg e, b u t yo u d on’t nee d to add a ny
he ad p ress u re to the nomo g r ap h.
The nomograph is now complete. The TK of our job
can be calculated like this:
TK = (P S I x yd
3
/hr)
÷
19
We need a unit that is capable of 925 PSI, and 60 yd
3
/
hr. The TK of this job is:
TK = (925 x 60
) ÷
19
TK = 55,500
÷
19
TK = 2921
The unit must have a TK of over 2921 and it must be
able to pump 60 yd
3
/hr and 925 PSI Sim u lt a neo u sly.
Look at the pump shown in our sample nomograph
(Figure 72).
• Can the unit pump at 925 PSI - YES
• Can the unit pump 60 yd3/hr? - YES
• Can the unit pump both simultaneously? - NO!
This unit will not do the job.
The engine is a little bit too small. The intersection of
60 yards
3
/hr and 925 PSI has been plotted for visual
representation, but you can see immediately that the
TK of the job (2921) is bigger than the TK of the unit
(2775). The curved black line represents the TK of the
unit. If the unit is going to be able to handle the job, the
intersection of pressure and yds
3
/hr will be to the right
and down from the curved line. Anything to the left or
above the line is beyond the power of the engine. What
if we could order this same unit with a slightly bigger
engine? The TK of the bigger engine is 3300. This
should work. Plotting the intersection of our
hypothetical job again, you can see that it falls within
the power zone of the engine (Figure 73).
Figure 72
I s thi s unit s ufficient for the job?
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