Video narration
PSG equations alone do not make a complete gear-pump design. Use a linked calculation sheet: each result feeds the next check. Confirm whether the machine is an external gear pump, then select the PSG Design Data Book edition and units. Start by recording flow, pressure rise, speed, viscosity, temperature, and allowable limits. Now determine displacement-the volume delivered per shaft revolution-from flow, speed, and assumed volumetric efficiency, which accounts for leakage. Use the PSG tables and geometry relations to select tooth dimensions, width, and clearances. Then calculate pressure forces, torque, and power. Carry those loads into gear strength, shaft diameter, bearings, and sealing checks. Finally verify delivered flow, volumetric efficiency, leakage, allowable stress, and manufacturability. If any input is missing, dimensions remain assumptions, not results. A defensible design is your completed calculation sheet: duty first, gears next, then torque, strength, and leakage closed.