Milton Roy MILROYAL D, Инструкция по эксплуатации

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2
Instruction Manual
SECTION 1 - INSTALLATION
1.4.2 Suction Piping
1. If possible use metal or plastic tubing for the
suction line because tubing has a smooth inner
surface and can be formed into sweep bends,
thus decreasing frictional flow losses.
2. Suction piping must be absolutely air tight to
insure accurate pumping. After installation, test
suction piping with air and soap solution for
leaks.
3. A strainer should be used in the suction line to
prevent foreign particles from entering the liquid
end. Any measures which prevent foreign matter
from entering and fouling the ball checks will
give increased maintenance free service.
4. It is preferable to have the suction of the pump
flooded by having the liquid end located below
the level of the fluid in the supply tank.
5. When pumping liquids at temperatures near the
boiling point, provide sufficient suction head to
prevent “flashing’’ of the liquid into vapor when
it enters the liquid end on the suction stroke.
6. Suction piping need to be one or two sizes larger
than the liquid end suction fitting, ensure NPIP
(Net Positive Inlet Pressure).
7. Sealed piping, sufficient suction pressure,
and properly adjusted packing are absolutely
necessary for accurate and stable pump
operation.
1.4.3 Discharge Piping
1. Install adequate size pump to prevent excessive
pressure losses on the discharge stroke of the
pump. Maximum pressure at the discharge
fitting on the liquid end must be kept at or
below the maximum pressure rating as shown
on the pump data plate. The peak flow of
this type pump during the discharge stroke is
approximately three times the average flow rate
(because of harmonic motion of the plunger) and
discharge piping should be sized accordingly.
2. The pump will not deliver a controlled flow if
the discharge pressure is less than the suction
pressure. Piping should be arranged to provide
at least 5 psi (34.5 kPa) positive pressure
differential from the discharge side to the suction
side. There are a number of ways to create an
artificial discharge pressure, such as the use of
a vented riser or a back pressure valve.
1.5 SERVICE CONNECTIONS
1.5.1 Pump Drive
1. Check the nameplate data on the pump drive
(motor) and insure proper power supply is
available before making any connections.
2. Preferred motor shaft rotation is marked on the
drive side flange of the pump. Although severe
immediate damage will not occur if motor
rotation is incorrect, preferred rotation should
be observed. (See Maintenance Instructions,
Assembly of Gear Cage into Pump Housing.)
Where possible, correct drive rotation will be
established at shipment by the factory.
3. For drives other than constant speed electric
motors, refer to complete manufacturer’s
instructions and service information included
with pump.