Centrifugal Pump – 300B

This Oberdorfer close coupled style bronze self-priming centrifugal pump is equipped with high quality ball bearings permanently filled with grease for maintenance free operation. The main shaft seal is a mechanical face type seal of proven reliability. Unlike positive displacement pumps centrifugal pumps have larger internal clearances as the pressure is generated by centrifugal force and high liquid velocity. These pumps can handle impurities in the liquid and the flow in the discharge line may be throttled or shut off without the need for a relief valve.



  • Self-Priming to 20 Feet Suction Lift
  • Rugged Bronze Construction
  • Ideal for marine service (air conditioning, bilge, and sea water recirculating).
  • O-Ring Housing seal eliminates gasket problems
  • Auxiliary Connections – for convenient priming and draining
  • Multiple Mechanical Shaft Seal Options -for various applications
  • Pump Heads mount to Standard Footed Nema 56J Jet Pump Motors
  • Shafts : 416 Stainless, Nickel Alloy, or 316 Passivated Stainless
  • Multiple motor options including Explosion Proof
  • For Pedestal Style, see 30PB
  • Optional Lifting Handle


  • Max Flow: 22 GPM – 83.28 LPM
  • Max Pressure: 15 PSI – 1.03 BAR


Centrifugal pumps are designed for single rotation and are non reversible. Standard rotation is counter clockwise looking at the pump inlet port (clockwise facing pump shaft). Close coupled centrifugal pumps may be driven by a variety of power sources such as electric motors, hydraulic motors or air motors. Self priming centrifugal pumps must be operated in the horizontal position.


Capacity – Water 60°F – Gallons Per Minute

Maximum lift without foot valve is 10 feet.

Bronze pumps are suitable for most common liquids in the pH range from 4-11. If in doubt consult with factory or check the Oberdorfer™ Chemical Resistance Guide booklet. The temperature limit for bronze pumps is 212°F. Higher temperatures are possible with fluoroelastomer or Polytetrafluoroethylene (PTFE) seals. Centrifugal pumps are not well suited for pumping viscous liquids. Viscosities up to 2000 SSu may be handled resulting in reduced performance and efficiency.

Pump seal is mechanical carbon face type mated to ceramic wear face for maximum durability. Other seal components are made of Nitrile with low swell characteristics for compatibility with a wide range of liquids including many chemicals and solvents.


Up to 22 gallons per minute water flow and suction lift of 15 feet without a foot or check valve (25 foot suction lift using a foot or check valve and a filled inlet line). A 1/2” pipe plug on the tank top is for initial filling of priming chamber and inlet line-pump priming is automatic thereafter.


Note: Seal and shaft modifications below are not physically interchangeable. Consult factory for modification data.

Fluoroelastomer, A Solvent Mechanical Seal: Mechanical seal for oils, fuels, lubricants, most mineral acids, and many solvents that attack other rubbers such as Carbon Tetrachloride, toluene, benzene, and xylene.

Polytetrafluoroethylene (PTFE) Mechanical Seal: For virtually all industrial chemicals, corrosives and solvents – as limited by compatibility of basic pump metal of construction.