流量计故障诊断.ppt

Click to edit Master title style,*,Click to edit Master text styles xxxxxxxxxxxxxxxxxx,Second level,Third level,Jan.24th,2004,故障诊断指南,數顯靶式,流量計,SBL,型,數顯靶式流量計,1700R,型,Flow Meter,Troubleshooting Guideline,新安装还是旧表?,方法,1,Page 4,Page 7,旧,新,怀疑,Micromotion,有问题,管道无流量,Transmitter,有输出,管道有流量,Transmitter,无输出,管道有流量,Transmitter,输出不正确,Page 10,2,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道无流量,Vortex,有输出,(,Page 1 of 1),可能的原因:,1.,流量计受到振动或电磁干扰影响,:,检查:,明显的管道振动,Vortex,靠近大的电磁干扰源,(,电机,电炉,),技术措施:,通过275观察流量和频率值.见,Appendix A.,如果发生体频率,=50,或 60,Hz,有可能是电磁干扰,.(,HART,命令:1,4,3,2,1,3),增加流量计滤波-见,Appendix A.,滤波调整后能够消除大多数振动,但可能影响测量小流量哪里.,如果是分体安装,是否能改为一体化安装.,通过加支撑来改善振动影响.,工程措施:,将流量计翻转90度.改变受振动影响的方向.,如果实在不行,安装一个缩径涡街,(8800,CR Reducer Vortex),可能解决问题-改变测量频率.,3,可能的原因:,1.,电源没有正确安装,Items to look for:,4,mA,无变化,或没有信号输出,技术措施,检查接线,2.,流量计方向装反,检查:,4,mA,无变化,或在高流量时也非常小,技术措施,确保箭头方向与流量一致.,3.,组态不正确,检查:,Vortex,测量质量流量还是标准体积流量,流量计上游不满足,35,D,而且,Installation Effects”,输入不正确,工程/技术措施:,验证流量计,Basic Setup,参数是否正确.,见,appendix A.,验证密度,(,用于质量)或密度比,(,用于标准体积,),是否正确,.,验证,“,Installation Effects”,是否正确,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,无输出-新安装,(,Page 1 of 3),4,可能的原因:,4.,流量低于小流量切除:,检查:,阀门是否完全开启,技术/工程措施:,开大阀门,增加流量,验证过程状态和流量计口径以确保实际流量高于仪表的小流量切除.,提高仪表灵敏度-见,appendix A.,可以调节滤波来读取低流量,但是对振动会较敏感.,如果实际流量大大低于小流量切除,可能需要更换缩径涡街.,5.,不满管,检查:,流量计是否竖直安装且介质向下流.,流量计读数间歇性-但是大多数时间无显示,技术/过程措施:,将流量计水平安装或竖直向上流,6.,气蚀/气化,检查:,管道压力接近气化压力,管道压力极低和/或流速极高,技术/工程措施,验证过程状态和流量计口径以确保背压足够.,尝试提高管道压力.或者,-,逐渐关小下游阀提高背压(阀门可能会几乎关死).,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,无输出-新安装,(,Page 2 of 3),5,可能原因:,7.,堵塞/挂壁,检查:,介质含有大块固体颗粒.,流量计垫圈伸进流体.,技术措施,检查上游垫圈是否堵塞流量,附加工程措施,开闭阀门以,清洗,流量计,.,可能会将发生体上的附着物冲出.,实在不行,则要拆卸流量计来清洁.,8.,电子部件故障,技术/工程措施,根据,Appendix A,完成电子部件的故障诊断,9.,传感器故障,检查:,介质温度是否超过压电传感器的耐温.,对于蒸汽,团流或水击可能损坏流量计,技术/工程措施,根据,Appendix A.,完成压电传感器故障诊断,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,无输出-新安装,(,Page 3 of 3),6,POTENTIAL ROOT CAUSES:,1.,电子部件故障,技术/工程措施,根据,Appendix A,完成电子部件的故障诊断,2.,传感器故障,检查:,介质温度是否超过压电传感器的耐温.,对于蒸汽,团流或水击可能损坏流量计,技术/工程措施,根据,Appendix A.,完成压电传感器故障诊断,3.,流量低于小流量切除:,检查:,过程状态变化会影响流速和/或密度.,工程措施:验证过程状态和流量计口径以确保实际流量高于仪表的小流量切除.,提高仪表灵敏度-见,appendix A.,可以调节滤波来读取低流量,但是对振动会较敏感.,如果实际流量大大低于小流量切除,可能需要更换缩径涡街,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,无输出-旧表,(,Page 1 of 3),7,可能的原因:,4.,不满管,检查:,流量计是否竖直安装且介质向下流.,流量计读数间歇性-但是大多数时间无显示,技术/过程措施:,将流量计水平安装或竖直向上流,5.,气蚀/气化,检查:,管道压力接近气化压力,管道压力极低和/或流速极高,技术/工程措施,验证过程状态和流量计口径以确保背压足够.,尝试提高管道压力.或者,-,逐渐关小下游阀提高背压(阀门可能会几乎关死).,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,无输出-旧表,(,Page 2 of 3),8,POTENTIAL ROOT CAUSES:,6.,堵塞/挂壁,检查:,介质含有大块固体颗粒.,流量计垫圈伸进流体.,技术措施,检查上游垫圈是否堵塞流量,附加工程措施,开闭阀门以,清洗,流量计,.,可能会将发生体上的附着物冲出.,实在不行,则要拆卸流量计来清洁,堵塞/挂壁,检查:,介质含有大块固体颗粒.,流量计垫圈伸进流体.,技术措施,检查上游垫圈是否堵塞流量,附加工程措施,开闭阀门以,清洗,流量计,.,可能会将发生体上的附着物冲出.,实在不行,则要拆卸流量计来清洁,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,无输出-旧表,(,Page 3 of 3),9,问题:读数持续偏高或偏低,可能的原因:,1.,组态不正确,检查:,Vortex,测量质量流量还是标准体积流量,流量计上游不满足,35,D,而且,Installation Effects”,输入不正确,以什么作为参考?,工程/技术措施:,验证流量计,Basic Setup,参数是否正确.,见,appendix A.,验证密度,(,用于质量)或密度比,(,用于标准体积,),是否正确,.,验证,“,Installation Effects”,是否正确,涡街是否测量是准确的.,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,输出不正确,(,Page 1 of 5),10,问题,:,读数远远低于正常值,而且变化不显著,可能的问题:,1.,堵塞/挂壁,检查:,介质含有大块固体颗粒.,流量计垫圈伸进流体.,技术措施,检查上游垫圈是否堵塞流量,附加工程措施,开闭阀门以,清洗,流量计,.,可能会将发生体上的附着物冲出.,实在不行,则要拆卸流量计来清洁,堵塞/挂壁,检查:,介质含有大块固体颗粒.,流量计垫圈伸进流体.,技术措施,检查上游垫圈是否堵塞流量,附加工程措施,开闭阀门以,清洗,流量计,.,可能会将发生体上的附着物冲出.,实在不行,则要拆卸流量计来清洁,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,输出不正确,(,Page 2 of 5),11,问题,:,流量变化时读数不变,可能的问题,:,1.,流量计受到振动或电磁干扰影响检查:,明显的管道振动,Vortex,靠近大的电磁干扰源,(,电机,电炉,),技术措施:,通过275观察流量和频率值.见,Appendix A.,如果发生体频率,=50,或 60,Hz,有可能是电磁干扰,.(,HART,命令:1,4,3,2,1,3),增加流量计滤波-见,Appendix A.,滤波调整后能够消除大多数振动,但可能影响测量小流量哪里.,如果是分体安装,是否能改为一体化安装.,通过加支撑来改善振动影响.,工程措施:,将流量计翻转90度.改变受振动影响的方向.,如果实在不行,安装一个缩径涡街,(8800,CR Reducer Vortex),可能解决问题-改变测量频率,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,输出不正确,(,Page 3 of 5),12,问题,:,流量不变时读数乱跳,可能的原因:,1.,脉动流或流量波动,检查:,流量计可能测量到真实的流量/泵的波动,而且阻尼较低.工厂默认,2,秒,.,工程/技术措施:,如果是闭环控制且动态响应时间非常重要,则根据,appendix A,增加阻尼.,2.,气蚀/气化,检查:,管道压力接近气化压力,管道压力极低和/或流速极高,技术/工程措施,验证过程状态和流量计口径以确保背压足够.,尝试提高管道压力.或者,-,逐渐关小下游阀提高背压(阀门可能会几乎关死).,3.,物体附着,检查:,流量是否间歇性下降,工程措施,检查是否有附着物.,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,输出不正确,(,Page 4 of 5),13,问题:,读数在低流量稳定,但是在高流量读数跌下来,可能的原因:,1.,气蚀/气化,检查:,管道压力接近气化压力,管道压力极低和/或流速极高,技术/工程措施,验证过程状态和流量计口径以确保背压足够.,尝试提高管道压力.或者,-,逐渐关小下游阀提高背压(阀门可能会几乎关死).,Rosemount 8800 Vortex Meter Troubleshooting Guideline,管道有流量,Vortex,输出不正确,(,Page 5 of 5),14,故障诊断指南,APPENDIX A,Rosemount Model 8800 Vortex,电子部件,Viewing Process Variables,Configuration,Filter Adjustments,Verifying Calibration,Appendix A-8800 Vortex,综述,压电传感器,Electrical Health,Mechanical Health,表体,16,Appendix A-,8800 Vortex,电子部件,电子部件,Viewing Process Variables,Configuration,Basic Setup&Installation Effects,Filter Adjustments,增加流量计灵敏度以测量低流量,增加流量计滤波以降低干扰和振动影响,滤波指南,Low Flow Cutoff,Low Pass Corner Frequency,Trigger Level,Optimize Flow Range:Filter Auto Adjust,Filter Restore,Verifying Calibration,4-20 ma(D/A)Trim,Internal Flow Simulation,External Flow Simulation,17,Appendix A-8800 Vortex Electronics,Basic Setup,组态,以下参数必须组态:,Service Type:,Liquid or Gas/Steam,PV Units:,Process Variable Flow Units(Volumetric or Mass),Range Values:,Set Lower Range Value(LRV)and URV(Upper Range Value).4 and 20 ma points in Analog,Process Temperature:,Nominal Process Temperature and units for Thermal Expansion calculations,Mating Pipe ID:,Inside Diameter of mating Pipe I.D.for Entrance Effect Correction,K-factor:,Reference K-factor determined in Flow Lab.Stamped on meter tag.,18,Appendix A-8800 Vortex Electronics,Basic Setup,组态-,HART 275 Menu Tree,19,Appendix A-8800 Vortex Electronics,Basic Setup,组态-,HART 275 Menu Tree,20,每个流量计的,Reference K-factor,是在,Rosemount Flow Lab,标定的.以下是各个口径的额定,K-Factors.,Appendix A-8800 Vortex Electronics,Basic Setup,组态,-,Reference K-factor,21,Electronics,Viewing Process Variables,Configuration,Basic Setup&Installation Effects,Filter Adjustments,增加流量计灵敏度以测量低流量,增加流量计滤波以降低干扰和振动影响,滤波指南,Low Flow Cutoff,Low Pass Corner Frequency,Trigger Level,Optimize Flow Range:Filter Auto Adjust,Filter Restore,Verifying Calibration,4-20 ma(D/A)Trim,Internal Flow Simulation,External Flow Simulation,Appendix A-,8800 Vortex Electronics,22,增加灵敏度以测量低流量,降低,Trigger Level,增加灵敏度,-,在测量低流量的低密度气体时必须,.,干扰可能影响精度,增加,Low Pass Filter,对于大多数应用不推荐,在测量低密度气体时必须,干扰可能影响精度,降低,Low Flow Cutoff,提高量程,干扰可能影响精度,Appendix A-8800 Vortex Filter Adjustments,增加流量计灵敏度以扩展量程,23,增加流量计滤波以降低干扰,增加,Trigger Level,在所有频率段降低灵敏度,在量程的,10-20%,可有效解决问题,降低,Low Pass Filter,在量程的30%-,100%,降低灵敏度,增加,Low Flow Cutoff,在量程的 10%以下降低灵敏度,减小量程,Appendix A-8800 Vortex Filter Adjustments,增加流量计滤波以降低干扰,24,Trigger Level,Above Trigger Level=Counted,Below Trigger Level=Not Counted,Appendix A-8800 Vortex Filter Adjustments,滤波指南:,Vortex,信号原理,25,Trigger Level,Appendix A-8800 Vortex Filter Adjustments,Vortex,信号和未经滤波的高频及低频干扰,26,Trigger Level,Appendix A-8800 Vortex Filter Adjustments,滤波指南:,Vortex,信号原理,干扰被小流量切除,ADSP,和低通滤波限制到低于,Trigger Level,Preferred“Signal to Trigger”Ratio(Signal Strength)is 4:1,Signal Amplitude,27,Appendix A-8800 Vortex Electronics,滤波指南:,Vortex,信号原理,High,Pass,Low,Pass,Low Pass Corner Frequency,Low Flow Cut-Off,2,HZ,7200,HZ,ADSP Filter Tracking,28,Appendix A-8800 Vortex,综述,压电传感器,Electrical Health,Mechanical Health,表体,电子部件,Viewing Process Variables,Configuration,Filter Adjustments,Verifying Calibration,29,Sensor and sensor lead wire can be checked for shortsAppendix A-8800 Vortex Sensor,压电传感器-电气状态诊断,1.,Loosen the three housing rotation screws with Allen head wrench,2.Slowly pull electronics housing-NOT MORE THAN 2 INCHES from top of support tube(To avoid damage to lead wire).,3.Loosen and remove sensor cable nut(using a 5/16”wrench,),4.,Using Multi-meter touching co-axial connector pin (and grounded to meter body),verify that sensor impedance is 5,megohms,.,5.If multi-meter reads short,sensor must be replaced*.,*-,Although no process seal is broken,it is recommended that the pipe be de-pressurized when replacing sensors,30,只有当其它的潜在故障点都排除后才建议检查机械损坏,.,Sensor/Post interface,非常重要,在移开和插入传感器时易损坏,.,传感器应该和接头紧密结合.如果其很容易地被移开,则有可能被团流或水击损坏,需要更换传感器.,Sensor/Post interface,应该是圆的.如果其损坏,会变成椭圆型.,传感器最多只能拆卸一次!,Sensor/Post Interface,Appendix A-8800 Vortex Sensor,压电传感器-检查机械损坏,*-,Although no process seal is broken,it is recommended that the pipe be de-pressurized when replacing sensors,31,Appendix A-8800 Vortex,综述,压电传感器,Electrical Health,Mechanical Health,表体,电子部件,Viewing Process Variables,Configuration,Filter Adjustments,Verifying Calibration,32,Appendix A-8800 Vortex Meter Body,Meter Body-Potential for Plugging,Corrosion,In general,issues with the meter body or shedder bar are very rare.,Rosemount 8800 meter body design has no ports or crevices to plug.,Very large chunks or large obstructions(,ie,-hard hats,building materials,etc)may become lodged on the shedder bar and cause poor or no reading.,As a final option,process may need to be shutdown to check for this,but only if it is suspected and all other options have been exhausted.,The 8800 Vortex performance is nearly insensitive*to shedder bar wear(,erosion,).,*-Even some erosion of shedder bar edge does not significantly impact ability to shed consistent vortices.,Proper material of construction selection is important to minimize potential for,corrosion,All Cast/All Welded,*No Crevices,*No Gaskets,33,