... 3. simple, stable, convenient, long service life pumping unit 1. API Spec 11E pumping unit 2.Conventional beam pumping unit 3 ... ” mechanism , facilitating wellhead operations.Gear reducer adopts herringbone involute or double circular toothed gear, high precision, nice load bearing capacity, and ... , 33, 2357,000C-57D-76-427,60042, 33, 2357,000 API Conventional Beam Pumping Unit