Oberdorfer 172B Bronze Centrifugal Pump End — Reliable Flooded Suction Circulation Without the Motor
The Oberdorfer 172B is a pump end only — no motor included — built entirely from corrosion-resistant bronze, making it a smart choice when you already have a motor or need to source one separately for your specific voltage and application. The pump features a bronze impeller, a Buna mechanical shaft seal, and 3/4-inch NPT inlet and outlet ports, delivering flows up to 18 GPM with a maximum pressure of 7 PSI. The passivated 316 stainless steel shaft adds another layer of durability, and the single open-vane impeller design runs quietly without contacting other pump components — which translates directly to a longer service life and lower maintenance demands.
What makes the 172B particularly versatile is how broadly it applies across industries. It handles water, oils, and a range of mild solvents up to 212°F, and can manage viscous liquids up to 2,000 Saybolt Seconds Universal — though flow and pressure will decrease as viscosity increases. Whether you're running coolant through a heat exchanger, circulating fluid in an industrial process loop, managing a hot water distribution system, or setting up a closed-circuit chemical circulation application, the 172B's heavy-duty bronze construction and straightforward flooded-suction design give you a reliable, long-lasting foundation to build around.
Key Features
- Pump end only — no motor included; pairs with your choice of AC or DC motor
- Heavy-duty corrosion-resistant bronze housing and bronze impeller
- Passivated 316 stainless steel shaft for added corrosion resistance
- Single open-vane rotating impeller — quiet operation, no contact with pump body
- Buna (Nitrile) mechanical shaft seal standard; Viton seal available as an option
- Carbon and ceramic rotary face mechanical seal for positive sealing
- Discharge line can be fully shut off without risk of motor overload or line bursting
- Compact and lightweight design for space-constrained installations
Applications
- Closed-circuit fluid circulation systems
- Hot water and coolant circulation (central heating, engine cooling circuits)
- Radiator and heat exchanger circulation
- Industrial process fluid loops
- Chemical circulation (mild solvents and compatible fluids)
- Liquid transfer for water, oils, and water-based solutions
- Washdown and general low-pressure pumping
- HVAC fluid circulation
Specifications
- Part Number: 172B
- Pump Type: Centrifugal, pump end only (no motor)
- Construction: Bronze housing, bronze impeller
- Shaft Material: Passivated 316 stainless steel
- Seal Type: Buna (Nitrile) mechanical seal standard; Viton optional
- Inlet Port Size: 3/4" NPT
- Outlet Port Size: 3/4" NPT
- Maximum Flow Rate: 18 GPM
- Maximum Pressure: 7 PSI
- Maximum Head: 17 feet
- Maximum Temperature: 212°F (100°C)
- Maximum Shaft Speed: 3,700 RPM
- Maximum Viscosity: 2,000 Saybolt Seconds Universal
- Installation Requirement: Flooded suction only (not self-priming)
- Compatible Fluids: Water, water solutions, oils, mild solvents, commercial chemicals (verify compatibility for specialty fluids)
Frequently Asked Questions
Q: Does the Oberdorfer 172B come with a motor?
No. The 172B is a pump end only. It does not include a motor. This allows you to pair it with an AC or DC motor that matches your voltage, speed, and enclosure requirements.
Q: Is the 172B self-priming?
No. This pump requires flooded suction — it must be installed below the liquid level so that fluid flows to the pump by gravity. It is not suitable for installations where the pump sits above the fluid source.
Q: Can the pump run dry safely?
No. Running this pump dry will damage the mechanical seal and impeller. Always ensure the pump is fully primed and the liquid source is at or above the pump level before starting.
Q: What seal material options are available?
The standard seal is Buna (Nitrile), suitable for water, oils, and mild solvents up to 212°F. A Viton seal is available as an option for applications involving more aggressive fluids or higher temperature needs up to 400°F.
Q: Can the discharge line be closed while the pump is running?
Yes. Because the flow produced is not positive displacement, the discharge line can be shut off completely without danger of overloading the motor or bursting lines. Flow can also be conveniently throttled using a valve on the discharge side.
Q: What pipe fittings are needed to connect the 172B?
Use 3/4-inch pipe fittings with PTFE pipe joint tape or thread sealant compound on both the inlet and outlet connections.
Q: Can this pump handle chemicals beyond water?
Yes, within limits. It is rated for water, water solutions, oils, and a wide range of mild commercial solvents. For specialty or aggressive chemicals, contact Oberdorfer directly to verify material compatibility before use.
Q: What is the repair kit for the Oberdorfer 172B?
The compatible repair kit for the 172B is Oberdorfer part number 11071. It is available separately and covers standard seal and wear component replacement.
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