Oberdorfer N9000R-S3 Bronze Pedestal Gear Pump — Reliable Positive Displacement Performance with Buna Lip Seal
The Oberdorfer N9000R-S3 is a high-quality bronze pedestal-mounted rotary gear pump end engineered for consistent, dependable fluid transfer across a wide range of industrial and commercial applications. Built with a bronze housing, cast bronze gears, and a 303 stainless steel shaft, this pump delivers the corrosion resistance and mechanical durability that demanding environments require. The Buna (NBR) lip seal is a distinguishing feature of the S3 configuration — it provides effective shaft sealing and is designed for easy field replacement, simply press out the old seal and press in a new one without specialized tools. An O-ring cover seal adds an additional layer of leak protection, making this pump end a practical and maintainable choice for facilities and industrial operations that need reliable uptime.
As a positive displacement gear pump, the N9000R-S3 moves a precise, consistent volume of liquid with every shaft revolution, which means flow rate stays proportional to shaft speed regardless of discharge back pressure. This makes it particularly well-suited for metered transfer of fuels, oils, water, and mild chemicals where repeatability matters. The pump includes a factory-set internal bypass relief valve at 50 PSI to guard against over-pressurization, and is rated for discharge pressures up to 100 PSI for water and non-lubricating fluids, and up to 150 PSI for oils and lubricating liquids. Common applications include day tank diesel fuel transfer systems, wastewater effluent sampling, HVAC chilled and hot water service, general industrial water service, and municipal water infrastructure. This pump end ships without a motor and is compatible with close-coupled adapter kits for mounting to standard NEMA and IEC motor frames.
Key Features
- Buna (NBR) lip seal for effective shaft sealing — easily field-replaceable without special tools
- Built-in internal bypass relief valve, factory set at 50 PSI
- Bronze pump housing and cast bronze gears for corrosion resistance
- 303 stainless steel shaft and fasteners
- Self-lubricating carbon-graphite bearings — no lubrication required
- O-ring cover seal for maximum leak protection
- Positive displacement design — consistent flow regardless of back pressure
- Self-priming capability with suction lift up to 20 feet
- Compatible with close-coupled adapter kits for NEMA and IEC motor frames
- Bare-shaft pump end only — motor sold separately
Applications
- Day tank diesel fuel transfer systems
- Wastewater effluent sampling from canals and treatment sites
- General industrial water service and circulation
- HVAC chilled water and hot water systems
- Municipal drinking water distribution
- Sprinkler and irrigation systems
- Oil transfer and lubrication systems
- Chemical transfer for mild, compatible fluids (pH 4–10)
Specifications
- Part Number: N9000R-S3
- Pump Type: Rotary positive displacement gear pump
- Construction: Bronze housing, cast bronze gears
- Shaft Material: 303 stainless steel
- Shaft Seal: Buna (NBR) lip seal
- Cover Seal: O-ring
- Bearings: Carbon-graphite, self-lubricating
- Inlet Port Size: 1" NPT
- Discharge Port Size: 1" NPT
- Maximum Flow Rate: 23 GPM
- Maximum Pressure (Oil/Lubricants): 150 PSI
- Maximum Pressure (Water/Non-Lubricants): 100 PSI
- Maximum Shaft Speed: 1,750 RPM
- Viscous Liquid Max Speed: 1,150 RPM
- Maximum Viscosity: 50,000 SSU
- Temperature Range (Metals): -40°F to 400°F
- Temperature Limit (Buna Seal): 212°F
- Relief Valve: Internal, factory set at 50 PSI
- Motor: Not included
- Mount Type: Pedestal / base mount
Frequently Asked Questions
Q: Does the Oberdorfer N9000R-S3 come with a motor included?
No. The N9000R-S3 is a bare-shaft pump end only and does not include a motor. It is designed for base-mount or pedestal installation and can be paired with a motor using available close-coupled adapter kits compatible with standard NEMA and IEC motor frames.
Q: What is the difference between the N9000R and the N9000R-S3?
Both are bronze pedestal gear pump ends with internal relief valves and identical port configurations. The key difference is the shaft seal: the standard N9000R uses a packing ring seal, while the N9000R-S3 uses a Buna (NBR) lip seal, which offers a different sealing method and is easier to replace in the field.
Q: Can the N9000R-S3 handle viscous fluids like heavy oils?
Yes, within limits. This pump supports fluids with viscosities up to 50,000 SSU. However, for viscous liquids, shaft speed should be reduced to 1,150 RPM or lower to maintain performance and protect the pump from excessive wear. The maximum rated speed of 1,750 RPM applies only to lower-viscosity fluids.
Q: Is the N9000R-S3 suitable for handling fuel such as diesel?
Yes. This pump has a long track record in day tank diesel fuel transfer systems. The bronze and stainless steel construction is compatible with diesel fuel, and the positive displacement design ensures consistent metered transfer. The fluid should be clean and free of abrasives for best pump longevity.
Q: What happens if the discharge line is closed while the pump is running?
The internal bypass relief valve is designed to handle momentary pressure spikes, but it is not intended as a flow control device. If the discharge line remains completely closed for more than 5 to 10 minutes, heat buildup can occur and potentially damage the pump. Always ensure adequate flow or controlled system shutdown when operating this pump.
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