Oberdorfer N994RH-M48 Gear Pump and motor unit

The Oberdorfer N994RH-M48 is a Bronze Gear Pump and motor unit, with built in Internal Relief Valve, Bronze Gears, Buna Lip Seal, 1/2 Inch NPT by 1/2 Inch NPT Ports, fitted with a 56C Frame motor adapter bracket, and is close coupled to a 3/4 HP, Single Phase, 56C Frame, 1140 RPM, 115/230V, TEFC Motor. This gear pump can pump most common liquids, and is suitable for water, oil, and mild compatible chemicals in the pH-range from 4-10, as well as diesel fuel. The close tolerances of the gears in this pump require clean liquids with no abrasives, as abrasives will wear down the pump and cause poor performance. Gear pumps are positive displacement pumps and each shaft revolution displaces a definite amount of liquid relatively unaffected by the back pressure in the discharge line. The shaft speed and flow are directly proportional, as the flow increases with speed increase, and the power demand (horsepower) increases with shaft speed and discharge pressure. This pump is self-priming, and the maximum suction lift for this pump is 20 feet, however, the suction line should be as short as possible. A relief valve is necessary to protect the pump and system if the discharge line becomes blocked or closed. This pump has an integral built-in relief valve which is not intended to be a metering or flow control device. Its main purpose is to function as a discharge pressure relief when the spring tension is exceeded by the discharge pressure causing it to bypass internally. The relief valve is always on the discharge side in this pump series. The factory pressure setting on this relief valve is 50 PSIG. To increase bypass pressure, just turn the relief valve adjusting screw in a clockwise direction. This pump is equipped with a lip seal with a metal case, that are spring energized, and single lip type. These are intended to provide minimum friction drag with positive sealing. These lip seals are easily replaced by pressing out the old seal and pressing in a new replacement. The pump has an O-ring cover seal for maximum leak protection. The bearings in this pump are designed of high performance carbon-graphite material selected for wear resistance and long service life that require no lubrication. The recommended discharge pressure limits for this pump are 100 PSI for water and non-lubricants, 150 PSI for oil and other lubricants, as the high pressure will accelerate wear.