A relatively low-cost personal-computer-based system is used to condition monitor a servo-valve-motor speed control system. Line pressures-flowrates together with motor torque-speed are monitored via 12 bit analogue to digital converters, and a set of performance characteristics are transformed into a mathematical model for the system in its run-in condition. Leakage flows are then introduced from each line, to simulate the onset of failure, and across the lines to simulate motor cross-port leakage deterioration. A graphics and software package is then developed and used to indicate which of the faults is occurring.
Get full access to this article
View all access options for this article.
References
1.
HuntT. M.A review of condition monitoring techniques applicable to fluid power systemsSeventh International Fluid Power Symposium, September 1986, Bath, pp. 285–294.
2.
MbariP. N.McCandlishD.Reliability and fault tree analysis in hydraulic systemsSeventh International Fluid Power Symposium, September 1986, Bath, pp. 303–311.
3.
WattonJ.Condition monitoring in hydraulic systems. South Wales Institute of Engineers Lecture, September 1987; to be published in the Proceedings.
4.
BrownF. T.DuanC. B.Measurement of surface temperature differentials as indicators of hydraulic pressure drop and flowSeventh International Fluid Power Symposium, September 1986, Bath, pp. 121–129.
5.
Qian Ziang-Sheng and Dai Neng-Cai.Identification of energy loss in fluid power system. Fluid Control and Measurement, Society of Instrument and Control Engineers, Japan, 1986, pp. 249–256. (HaradaM.) (Pergamon PressOxford).
6.
WittK.SchlosserW. M. J.Thermodynamic measurements on hydraulic components. ICMES Conference, Paris, 1977.
7.
SasakiA.DunthorneD. M.Electrostatic liquid cleaning of hydraulic fluids. IMechE conference on Contamination control in hydraulic systems, Bath, 1984, pp. 111–118. (Mechanical Engineering Publications, London).
8.
DayM. J.WayN. R.ThompsonK.The use of particle counting techniques in the condition monitoring of fluid power systems. Condition monitoring 1987 (JonesM. H.), 1987, pp. 322–339. (Pineridge Press).
9.
HuntT. M.TilleyD. G.Techniques for the assessment of contamination in hydraulic oils. IMechE conference on Contamination control in hydraulic systems, Bath, 1984, pp. 57–63. (Mechanical Engineering Publications, London).
10.
McCullaghP.Ferrography and particle analysis in hydraulic power systems. IMechE conference on Contamination control in hydraulic systems, Bath, 1984, pp. 65–77. (Mechanical Engineering Publications, London).
11.
PriceA. L.RoylanceB. J.ZieL. X.The PQ—a method for the rapid quantification of wear debris. Condition monitoring 1987 (JonesM. H.) 1987, pp. 391–405. (Pineridge Press).
12.
RawI.A particle size analyser based on filter blockage. Condition Monitoring '87, (JonesM. H.), 1987, pp. 875–894. (Pineridge Press).
13.
LewisR. T.Analysis of ferrous wear debris. Condition Monitoring 1987 (JonesM. H.), 1987, pp. 360–370. (Pineridge Press).
14.
WatkinsK.WattonJ.Wear monitoring of positive displacement monitoring. 2nd Annual Conference on Condition Monitoring, London, May 1988.
15.
KibbleJ. D.Flow metering and other means for checking fluid systems. Condition Monitoring 1987 (JonesM. H.) 1987, pp. 863–874. (Pineridge Press).
16.
ZemerlyM. J. A.Wear characteristics of vane pumps using water-based fluids. MSc thesis, Department of Mechanical Engineering and Energy Studies, University College Cardiff, 1985.
17.
HuntT. M.BakerD. J.PriestP. H.The utilisation of a micro-computer in the condition monitoring of a hydraulic pump. IMechE conference on Microprocessors in fluid power engineering, Bath, 1984, pp. 111–119.
18.
LewisD. C.AskeyA. McD.On-line monitoring of mining hydraulic systems. Microprocessors in fluid power engineering, Bath, 1984, pp. 121–128.
19.
PriestP. H.BakerD. J.A modular microprocessor data acquisition system for hydraulic pump research, Microprocessors in fluid power engineering, Bath, 1984, pp. 129–137.
20.
ToetG.A determination of the theoretical volume of hydrostatic displacement pumps and motors from volumetric measurementsHydraulic Pneumatic Power, June 1970, 346–356.
21.
WilsonW. E.Performance criteria for positive-displacement pumps and fluid motorsTrans. ASME, 1949, paper 48-SA-14.
22.
SchlössorW. M. J.A mathematical model for displacement type pumps and motorsOelhydraulik and Pneumatik, 1961, 252–257.
23.
SchlössorW. M. J.The overall efficiency of positive displacement pumps. First BHRA Fluid Power Symposium, 1969.
24.
ZarottiG. L.NervegnaN.Pump efficiencies approximation and modelling. Sixth BHRA Fluid Power Symposium, 1981.
25.
GorodezriK. J.The mathematical model of hydrostatic machinesProc. 3 Fachtangung Hydraulik and Pneumatik, 1979, 3.
26.
McCandlishD.DoreyR.Steady-state losses in hydrostatic pumps and motors. Sixth BHRA Fluid Power Symposium, 1981.
27.
McCandlishD.DoreyR. E.The mathematical modelling of hydrostatic pumps and motorsProc. Instn. Mech. Engrs., Part B, 1984, 198(10), 165–174.
28.
HibiA.IchikawaT.Torque performance of hydraulic motor in whole operating condition from start to maximum speed and its mathematical model. Fourth BHRA Fluid Power Symposium, 1975.
29.
BownsD. E.RolfeA. C. J.A discussion of factors which affect motor torque under starting conditions. Fifth BHRA Fluid Power Symposium, 1978.
30.
ToetG.Test techniques for hydraulic systems and components and the interpretation of test results. The 1970 Fluid Power International Conference, London.
31.
RenvertP.WeiderW.The comparison of various test methods to determine the starting and low speed characteristics of hydraulic motors with regard to their practical use. Sixth BHRA Fluid Power Symposium, 1981.
32.
HelgesteadB. O.FosterK.BannisterF. K.Noise in an axial piston pump. Conference on Noise emitted by fluid power equipment, 1973 (Institution of Mechanical Engineers).
33.
FosterK.HannanD. M.Fundamental fluid borne and airborne noise generation of axial piston pumpsSeminar on Quiet hydraulic systems, 1977, pp. 29–40. (Institution of Mechanical Engineers, London).
34.
BownsD. E.McCandlishD.Pressure ripple propagation. Seminar on Quiet hydraulic systems, 1977, 93–102. (Institution of Mechanical Engineers, London).
35.
MartinK. J.TaylorR.Optimised port plate timing for an axial piston pump. Fifth BHRA Fluid Power Symposium, 1978.
36.
EdgeK. A.FreitasF.Fluidborne pressure ripple in positive displacement pump suction lines. Sixth BHA Fluid Power Symposium, 1981.
