Chapter 3 Hydraulic Pumps The operating principle of every pump in a hydraulic system depends upon the alternative change of their working volumes. Note:the piston diameter as d the offset of the eccentric wheel as e,the longest stroke the piston can reach as s and the discharged oil volume V then s 2e V=(πd2/4)s=(πd2/2)e As described above,the basic conditions that constitute a hydraulic pump can be concluded as follows: (1)Oil tight chamber. (2)Flow-deploying(separate the low pressure from the high one). (3)The absolute oil pressure in the reservoir should be equal or more than the atmospheric pressure. Homepage List Upwards Downwards Retumn ExitChapter 3 Hydraulic Pumps 4 The operating principle of every pump in a hydraulic system depends upon the alternative change of their working volumes. Note: the piston diameter as d, the offset of the eccentric wheel as e, the longest stroke the piston can reach as s and the discharged oil volume V, then As described above, the basic conditions that constitute a hydraulic pump can be concluded as follows: (1) Oil tight chamber. (2) Flow-deploying (separate the low pressure from the high one). (3) The absolute oil pressure in the reservoir should be equal or more than the atmospheric pressure. s e = 2 2 2 V d s d e = = (π / 4) (π / 2)