Crescent Internal Gear Pump
MFG in Columbia, KY USA
CIG (Crescent Internal Gear) pumps are produced primarily for fluid power applications and aircraft fuel test stands. They are available in multiple stages for very high pressure or moderate pressure on very low viscosity fuels. Pumps are also available in double pump configurations which share a common inlet port but deliver two independent flows for supporting multiple machine functions.
The patented tooth profile of CIG pumps avoids trapping fluid. The result is a very low pulsation, extremely quiet high efficiency pump. Single pumps are available in 54 different models and double pumps in over 1300 different combinations. Single pump flow rates from 1 to 125 GPM ( 4 to 475 L/M) with continuous pressure ratings to 5000 PSIG (345 BAR). Pumps are available in single and double configurations. The double pumps have a common inlet port and two independent discharge ports. Pumps can be provided in a number of staging arrangements allowing very high pressure capability or high pressure at low viscosity.
Perfectly suited to a wide variety of challenging applications, including:
• Hydraulic power
• Fatigue test equipment
• Marine hydraulics
• Liquid fuel injection
• Fuel component test equipment
- Low Pressure Ripple Typically less than 1% peak-to-peak at maximum pressure performance.
- Long Life Due to the patented gear tooth profile and its low Hertzian compression stresses during the meshing phase of the gears, plus the incorporation of the hydrodynamic principle.
- Reliability Excellent resistance to flow degradation when compared to most other pump designs.
- Durable materials, plus design simplicity, provide outstanding durability.
- Low Noise Typically less than 68 db(A) for most applications. The patented gear tooth profile reduces trapped fluid and backlash in the gears reducing pressure pulsations, keeping airborne noise to a minimum.
- Wide Speed Range Able to operate at high speed without a suction boost, while delivering excellent suction lift characteristics.
- Modular Design Space-saving single-, double- or triple-pump configurations where each pump shares a common drive shaft requiring only one driver.
- Wide Application Range Able to handle fluids with viscosities as low as 0.5 cSt and pressures up to 5000 PSI (345 BAR).
| CIG | Flow Range (1) | Flow Range (1) | Pressure Range (2) | Pressure Range (2) |
|---|---|---|---|---|
| Model | GPM | L/Min | PSI | BAR |
| 2*005 | 1.1 | 4.2 | 4000 | 275 |
| 2*006 | 1.6 | 6.1 | 4000 | 275 |
| 2*008 | 2.3 | 8.7 | 4000 | 275 |
| 3*010 | 2.9 | 11.0 | 4000 | 275 |
| 3*012 | 3.7 | 14.0 | 4000 | 275 |
| 3*016 | 5.3 | 20.1 | 4000 | 275 |
| 4*020 | 7.2 | 27.3 | 4000 | 275 |
| 4*025 | 9.3 | 35.2 | 4000 | 275 |
| 4*032 | 12.2 | 46.2 | 4000 | 275 |
| 5*040 | 15.3 | 57.9 | 4000 | 275 |
| 5*050 | 20.1 | 76.1 | 4000 | 275 |
| 5*063 | 26.1 | 98.8 | 4000 | 275 |
| 6*080 | 32.1 | 121.5 | 4000 | 275 |
| 6*100 | 41.9 | 158.6 | 4000 | 275 |
| 6*125 | 52.1 | 197.2 | 4000 | 275 |
| 8*160 | 67.4 | 255.1 | 4000 | 275 |
| 8*200 | 83.5 | 316.0 | 4000 | 275 |
| 8*250 | 105.1 | 397.8 | 4000 | 275 |
* Number of stages / Available 1 through 5 Stages
(1) At 1750 rpm / Capable of operating at higher and lower speeds - Contact Imo Pump
(2) Capable of operating at higher pressures - contact Imo Pump
Construction features
Design Characteristics:
Flow Range: 1 to 115 usgpm
Fluid Viscosity: .5cSt minimum
Inlet Pressure: 7psig (options available to allow 100+psig)
Differential Pressure: To 5000psig
Temperature: 180˚F (options to allow 250˚F+)
Speed: To 4500rpm (dependent on Frame size, inlet pressure and fluid viscosity)
Materials of Construction
Mounting Flange: Ductile Iron (nitride hardening optional)
Gear Housing(s): Ductile Iron (nitride hardening optional)
Rear Cover: Aluminum (steel optional)
Seal Housing: Aluminum (steel optional)
Ring Gear: Pearlitic Gray Iron (nitride hardening optional)
Pinion Gear: Alloy Steel (nitride hardened)
Shaft: Alloy Steel (nitride hardened)
Pump Barrel: Steel (multi-stage pumps only)
O-rings: Fluorocarbon
Shaft Seals: Teflon inner / Fluorocarbon outer lip type (mechanical seal optional)
Sleeve Bearings: Metal-Polymer composite
