This series of variable displacement vane pump, oil hydraulic circuit system for the needs of the design, it can improve circuit efficiency and reduce Sao tone, reduce the oil temperature, the energy input, the function becomes effective, to save power purposes. Suitable for grinding machines, automatic lathes, machine tools, shoe machinery, and other kinds of special machines or single-energy machine. VP-SF-15-A-20, VP-SF-15-B-20, VP-SF-15-C-20, VP-SF-15-D, VP-SF-20-A-20, VP- SF-20-B-20, VP-SF-20-C-20, VP-SF-20-D, VP-SF-30-A-20, VP-SF-30-B-20, VP-SF- 30-C-20, VP-SF-30-D, VP-SF-40-A-20, VP-SF-40-B-20, VP-SF-40-C-20, VP-SF-40- D VPKC-F8A1-01, VPKC-F12A2-01, VPKC-F15A3-01, VPKC-F20A4-01, VPJC-F15-C2-02-1, VPJC-F15-C2-01-1, VPJC-F20-C2 -02-1, VPJC-F30A4-01-1, VPJC-F40A4-01-1 VPKCC-F1212A1A1-01, VPKCC-F1515A2A2-01, VPKCC-F2020A3A3-01, VPKCC-F3030A4A4-01, VPKCC-F4040A4A4-01 VPKC -F23A1-1, VPKC-F26A2-1, VPKC-F30A3-1, VPKC-F40A4-1