Pump housings and gears are made of top quality bronze, shafts are 303 stainless steel. Bearings are made of high performance carbon-graphite material selected for wear resistance and long service life. Gear pumps are positive displacement pumps. Each shaft revolution displaces a definite amount of liquid relatively unaffected by the backpressure in the discharge line. Shaft speed and flow are directly proportional.
The pump by-pass is not intended to be a metering or flow control device. Its main purpose is to function as a pressure relief when the desired set point is exceeded, overheating can occur within 5 -10 minutes if the discharge line is completely shut off for extended periods. Reversing rotation reverses the “IN” and “OUT” ports and the location of the by-pass ports have to be reversed. The by-pass valve is factory set at 50 p.s.i. To increase the set point, turn the bypass valve adjusting screw in a clockwise direction.