... suitable for Beam Pumping Units application with special high slip (5 to 13%),very high starting torque and very soft mechanical ... 6 Poles 60Hz),1000RPM(6 Poles 50Hz),900RPM(8 Poles 60H),750RPM(8 Poles 50Hz).6,Rated frequency:60Hz(50Hz ... available on request) ,380V, 50HZ is also available 8,Service Factor:1.15 or 1.0.9,Protection Enclosure ... are follows: NEMA D motor for oilwell pump with high quality