Milton Roy MILROYAL D, Инструкция по эксплуатации

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5 Instruction Manual
SECTION 2 - OPERATION
2.2.3 Capacity Adjustment: Stroke Speed
Capacity of the MILROYAL
®
D Pump is
directly proportional to the input drive speed.
Most pumps are supplied with a constant speed
electric motor as the input power source. With a
constant speed input power source, the stroking
speed is established by the worm and worm gear
set installed in the pump housing, and may be
changed only by changing this gear set. The use
of a variable speed input power source, however,
allows continuous variation of stroking speed and,
therefore, output flow rate variation over a broader
range.
2.3 START- UP
2.3.1 General
All pumps are thoroughly tested under simulated
operating conditions before they leave the factory
to verify the pump capacity and to check the drive
motor for satisfactory operation at maximum rated
pressure. With the pump housing filled to the proper
oil level and all piping and electrical connections
made, the pump is now ready for start- up.
2.3.2 Packing
New packing, installed and shipped from the factory
in a complete pump or liquid end, has been “set’’
and run-in during production quality assurance
testing and requires no further breaking in for
start- up. During operation, if leakage does occur,
the gland nut should be tightened a little at a time
(1/6 turn or less) until leakage is minimized or
stopped. The packing should be allowed to resettle
at least five minutes between adjustments. If it is
possible to tolerate a little leakage at the gland,
the leaking liquid will help to lubricate and cool
the packing and plunger, greatly extending the life
of both.
2.3.3 Capacity Calibration
After the initial break-in period and adjustment of
the packing, test runs should be made to determine
the exact capacity of these controlled volume pump
under the specific operating conditions for various
stroke length settings. Usually it is necessary to
calibrate the pump at only three stroke length
settings to determine its characteristics throughout
the entire range. The settings normally used are
full stroke (100%), 50%, and 20% stroke length.
Two methods of measuring the capacity in a given
time limit can be used:
1. Measure the drop in liquid level from calibrated
vessel (preferred).
2. Measure the quantity collected from the
discharge side of the pump.
It is essential that the suction lines of controlled
volume pumps be absolutely free of entrapped
air or vapor to prevent gas movement into the
liquid end. Milton Roy liquid ends are designed
to rapidly discharge any small bubbles which
may enter. However, any large amounts of gas
in the liquid end is alternately compressed and
expanded with each plunger stroke and causes
inaccuracies in pumping. In severe case the liquid
end may become vapor bound and cease pumping
altogether.