C. DESCRIPTION OF EQUIPMENT
The AA3G Series pumps are positive displacement, rotary screw pumps consisting of a precision
bored housing that encloses a drive screw (power rotor) and two intermeshing driven screws (idler
rotors). These screws, when rotating, form a succession of closures or cavities. As they rotate, the
fluid is moved axially from inlet to outlet port in a continuous, uniform flow with minimum fluid pulsation
and pump noise.
D. ORDERING INSTRUCTIONS
All correspondence pertaining to renewal parts for equipment must refer to instruction manual number
and should be addressed to nearest Imo representative. The handling of renewal orders will be greatly
facilitated if the following directions are carefully observed:
1. Give the number of instruction manual with revision level and date.
2. Give the model number of the pump for which part is desired. This number appears on nameplate.
3. Designate desired part by the IDP number and name as shown on assembly drawing and as listed
in Table 2 in this instruction manual.
E. OPERATION
E-1
–
LIQUID LIMITATIONS
– Never operate with water. The pump is designed for liquids having the
general characteristics of oil.
E-2
–
OPERATING LIMITS
CAUTION
ATTENTION
Operating conditions, such as speed, fluid viscosity, temperature inlet pressure,
discharge pressure, filtration, duty cycle, drive type, mounting, etc., are interrelated.
Due to these variable conditions, specific application limits may be different from that of
operational limitations. This equipment must not be operated without verifying the
system’s operating requirements are within pump’s capabilities.
Table 1 – Pump Operating and Structural Limits
Maximum Speed .............................. 5000 RPM for –95 models and 4000 RPM for –118 to -162 models.
Viscosity ....................... 15000 SSU (3200 cSt) Max./ 1500 SSU (325 cst) Max. for Relief Valve models.
2.0 cst Minimum for all models.
NOTE:
Consult factory for allowable operating viscosity at specific speeds and pressures.
DO NOT
alter design viscosity without prior consultation with Imo Pump.
Temperature .................................................................................................... 0° to 225°F (-18° to 107°C)
Inlet Pressure .......................................................................................................... 50 psig (3.4 Bar) Max.
Differential Pressure ............................................................................................ 250 psig (17.2 Bar) Max.
Discharge Pressure ............................................................................................... 300 psi (20.7 Bar) Max.
Drive .......................................................................................................................................... Direct Only
Filtration ......................................................................................... See General Installation Manual, CA-1
Mounting ............................................................................................................... Foot or Flange Mounted
Shaft Rotation ....................................................................................... Available in CW or CCW versions.
Pump is
NOT
bi-rotational.
2
