Beam Pumping Units 1,Slow, Long Strokes; 2,belt Transmission; 3,low Torque Demand. Beam Pumping Units1,Slow, Long Strokes2,belt Transmission; ... the patent of American. It takes full advantages of all pumping units by years of research and development. As a unique ... engineering breakthrough, the 100% mechanical ROTAFLEX is especially suitable for producing high volume fluid in deep wells with rod pump ...