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Bronze Rotary Gear Pump - N999

Our Model N999 Bronze Gear Pump is a hallmark of quality and efficiency, suitable for a wide array of applications. Each component, from the housing and gears made of top-notch bronze to the 303 stainless steel shafts, is chosen for its durability and strength. The carbon graphite bearings are engineered for maximum wear resistance, ensuring a long and dependable service life.

This pump operates on the principle of positive displacement, delivering a consistent volume of liquid with each shaft rotation, effectively independent of back pressure variations in the discharge line. This means you get a steady flow that's directly related to the shaft speed, allowing for precise control over your fluid management.

Ideal Operating Parameters: For water and non-lubricants, the pump is rated for up to 100 PSI (6.9 bar), while it can handle up to 150 PSI (10.3 bar) for oil and other lubricating fluids. Its design accommodates a maximum shaft speed of 1750 RPM.

Standout Features:

  • Tough, corrosion-resistant bronze build for longevity
  • Space-saving close-coupled design for simple installation
  • Sturdy stainless steel shafts for enduring performance
  • High-quality bronze spur gears for reliable operation
  • Self-lubricating carbon graphite bearings that reduce maintenance
  • O-ring cover seal offering unparalleled leak protection
  • Standard Nitrile Lip Seal, with a fluoroelastomer option for demanding environments
  • Adaptable for easy field assembly to fit a range of motor frames

Expanded Pump Range:

  • For AC motor compact pump units, refer to our Close Coupled Bronze Adapterless Rotary Gear Pumps
  • For configurations requiring a mechanical seal, see our carbonator style – model N95060


Drive Mechanism

Our close-coupled pumps are designed for direct attachment to electric motors using an appropriate adapter bracket. A flexible coupling ensures a secure and efficient connection between the pump drive shaft and the motor shaft.


Liquid and Temperature Compatibility

The N999 is compatible with any liquid that bronze can handle, most commonly water, oil, and mild chemicals within a pH range of 4 to 11. For viscous liquids, operate at reduced shaft speeds of 1150 RPM or less. For guidance on these applications, please consult our factory. To ensure the longevity of your pump, avoid using it with liquids that contain solids, abrasives, powders, or paint pigments. The recommended temperature range for optimal pump life is from 32°F to 140°F (0°C to 60°C). For advice on more extreme conditions or to prevent potential freezing damage, reach out to our factory. Remember that cold oils can be especially viscous and may require a lower operating speed or additional power.


Suction Lift and Installation

To achieve the best results, place the pump as close as possible to the liquid source to minimize suction lift. Brand new, the N999 can lift water up to 20 feet (6.1 meters) through the suction line. We recommend using a foot valve with a strainer at the start of the suction line to help keep the pump primed and prevent dry running. The suction pipe should match the pump's inlet port size, but for longer or more viscous fluid lines, choose a larger pipe to ensure efficient flow.


Shaft Seals

The standard configuration includes a Nitrile lip seal, with the option to upgrade to a fluoroelastomer seal for more challenging conditions. To opt for the fluoroelastomer seal, simply add 'S5' to the pump model number when ordering.


Optional Relief Valve

In systems with throttling devices like valves or nozzles, a relief valve is crucial to protect against overpressure by redirecting liquid back to the suction side or tank. Our R-model pumps include an integrated relief valve for intermittent use to prevent overheating; however, it is not intended for continuous pressure or flow control. For such applications, install a separate relief valve in the pressure line. The factory default for the pump motor unit is for a counterclockwise shaft rotation from the pump shaft end. If the motor rotation is reversed, it's important to also adjust the "in" and "out" ports and relocate the relief valve, which is positioned on the inlet side for this series. The factory pressure setting starts at 50 PSIG (3.4 bar), but you can increase the pressure by turning the relief valve's adjusting screw clockwise.

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