JETStream TwinForce Series, Operation Manual

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31
TwinForce™ Series Waterblast Unit
Breaking in New Packing
1. Adjust the engine speed to 1400 rpm.
2. Adjust the discharge pressure to 3,000
psi (200 bar) by slowly closing the bypass
valve (all dump valves closed).
3. When the coolant temperature reaches
120° F (49° C), increase engine speed to
2100 rpm.
4. Continue to bring the discharge pressure
up to full operating pressure in about
three equal steps while operating 1 min-
ute for each step.
Check the lubrication water and carefully
feel the stuffing boxes for excess tem -
peratures. Stuffing boxes and gland nuts
should only be slightly warm to the touch
when the pump is running at the rated
operating pressure. Hot stuffing boxes
and gland nuts may be caused by insuf-
ficient water lubrication or tight fitting
packing. If insufficient lubrication water
flow cannot be corrected by readjusting
the needle valves, stop the pump and cor-
rect the problem.
ATTENTION
This procedure is only applicable for 15K and 20K
molded packing. It is not required for plastic
packing.
New packing must be broken in to prevent
damage and ensure optimal performance. Break-
in should occur in three to four pressure increases
over a 5 minute period.
Using the Hydro-Throttle (Dump
System Only)
The hydro-throttle allows the
operator to set an operating speed
for the engine to cycle between as
the control gun (or other device)
dumps pressure. This prevents
the pump operator from manually
adjusting the engine speed during
cycling. The engine will cycle from low idle to
the set speed as dictated by pump pressure.
To set the hydro-throttle:
1. Start with the switch in the MANUAL posi-
tion.
2. Raise engine rpm to the desired operating
engine speed and then move the switch
to the AUTOMATIC position. The control
panel will record this rpm into memory.
As the discharge device is cycled between
operating pressure and dumping (zero
pressure), the control panel will cycle the
engine between low idle and the operat-
ing rpm that was set by the operator. If
the switch is moved back to MANUAL, the
operator must reset the top threshold or
raise and lower engine speed manually
using the up/down buttons.