调节阀口径计算? 请教各位老师,关于 调节阀 口径,蓝色字体部分怎么理解,非常感谢。 Valve Sizing Sizing and calculations for control valves shall be based on manufactures standard. However, the calculations shall be checked against ANSI/ISA S75.01 “Flow Equations for Sizing Control Valves” or IEC 60534, Part 2 -1 “Flow capacity – Sizing equations for fluid flow under installed conditions”. The Cv of the valve shall be calculated on basis of 1.3 times the operating flow or of 1.2 times the maximum flow (the highest value is chosen). The calculated Cv value shall be corrected taking into account pipe reductions, cavitation, flashing and/or critical velocity. The allowable leakage rate shall be applied according to FCI 70.2 “Control Valve Seat Leakage”. There are applications where general sizing criteria do not apply: • Where pressure drop is predetermined by process conditions • Where expected static pressure variations and system contingencies indicate special consideration • Pressure drop allocated to a control valve in the suction, or discharge line of a centrifugal compressor, shall be 5% of suction absolute pressure or 50% of system dynamic losses (exclusive control valve) at the compressor rated point whichever is the largest. 查看更多1个回答 . 3人已关注