基于滤膜淤积法的油液污染在线监测系统

针对油液污染是导致液压系统故障的主要原因以及目前国内外油液污染大多不能实现在线监测的现状,提出基于滤膜淤积法的恒功率测量法,在保证功率恒定的情况下测量通过某一固定体积时的压差来间接测量油液的污染度。采用阀用直流电磁铁作为主推动力元件来推动特制液压缸内活塞杆来获得压降,自制金属滤膜作为传感元件,并设计了监控软件操作平台,完成了油液污染在线监测系统的设计、调试和试验工作。试验结果表明,该系统能给出相应的ISO、NAS及SAE油液污染等级,并有良好的人机交互能力。与离线测试装置相比,具有可信的精确度和实时性,可满足生产现场的使用要求,具有一定的推广应用价值。

OIL CONTAMINATION ON-LINE MONITORING SYSTEM BASED ON MEMBRANE FILTER SILTING METHOD

In view of oil contamination, the main reason cause faults of hydraulic system, and present development status that oil contamination mostly cannot be on-line monitored at home and abroad, constant power measurement based on silting method is proposed, namely, in the constant power situation, to obtain degree of oil contamination indirectly by measuring the differential pressure through some fixed volume oil. DC electromagnets of hydraulic valves are used as active force to propel piston rod of the purpose made cylinder to obtain differential pressure, special metal membrane filter as sensing element, operating platforms for monitor and control are developed, and design, debugging and experimentation for the oil contamination on-line monitor system are accomplished. The experimental results indicate that the system could produce corresponding ISO, NAS and SAE oil contamination classes, and had favorable man-machine interactive ability. Compared with the off-line test device, the system has credible precision and real-time performance, which can meet the demands of operation requirements of production field and has certain popularization value.