... efficiency is 58 higher than that of old Y-type oil pump;3. AY-type oil pump has same structural model, installation size ... and scope of performance parameter with old Y-type oil pump, which is good for the reconstruction of old ... ×2B, 250AYS150C50 ,250-inlet diameter (mm)A-first reconstruction, Y-centrifugal oil pump, S-first impeller double-suction,,material code of over ...