Paper: The Long Stroke Hydraulic Pumping Unit

The history of the successful long stroke hydraulic pumping unit is, when compared to the oil industry, a relatively short one. Attempts to build an hydraulic pumping unit were made as early as 1932 but without too much success. In 1939, two of the present day long stroke hydraulic pumping units were first brought out on the market to be offered to the oil industry. Since 1945 two more manufacturers of long stroke hydraulic pumping units have presented their equipment to the oil fields.