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Technical Diagnostics and Reliability of Hydraulic Mechanisms

* Exchange students do not have to consider this information when selecting suitable courses for an exchange stay.

Course Unit Code338-0323/03
Number of ECTS Credits Allocated5 ECTS credits
Type of Course Unit *Compulsory
Level of Course Unit *First Cycle
Year of Study *Third Year
Semester when the Course Unit is deliveredWinter Semester
Mode of DeliveryFace-to-face
Language of InstructionCzech
Prerequisites and Co-Requisites Course succeeds to compulsory courses of previous semester
Name of Lecturer(s)Personal IDName
HRU38doc. Dr. Ing. Lumír Hružík
DVO31Ing. Lukáš Dvořák, Ph.D.
BUR262Ing. Adam Bureček, Ph.D.
Summary
Study of the subject will provide knowledge from field of the diagnostics of hydraulic components and equipment with a sight on free of disassembly diagnostics. Parametric, vibrodiagnostic, tribotechnical and thermodynamic diagnostic methods of technical diagnostics are discussed. There are considered problems of reliability of hydraulic components and systems in the subject. There are described the instruments of technical diagnostics in terms of subject. Physical principles and metrological characteristics of sensors including the requirements on the sensors are given. There are described the sensors of diagnostic variables: pressure, flow, temperature, trajectory, speed, acceleration, force, moment, revolutions, noise and vibration. The basic diagnostic measurements of hydraulic and pneumatic components (hydro-generators, rotary hydro-motors, linear hydro-motors, compressors, pneumomotors, pressure valves, distributors and other flow elements) and systems are discussed. The subject also deals with operation simulation and monitoring of machines.
Learning Outcomes of the Course Unit
To acquaint students with the basic concepts of technical diagnostics and basic diagnostic methods. To acquaint students with problems of reliability of hydraulic components and equipment. To acquaint students with the sensors and measuring instruments in the technical diagnostics of hydraulic components and equipment and the problems of technical diagnostics of hydraulic components and equipment. To acquire experience in practical measurement and diagnostics of hydraulic components and equipment. To learn to work with measurement and diagnostic system M 5000 Hydrotechnik.
Course Contents
The program of lectures

Week lectures
1 Meaning and tasks of technical diagnostics. Terminology. Diagnostic
parameters. Technical Diagnostics Methods: parametric methods of diagnostics.
2 Methods of technical diagnostics: Vibrodiagnostics, measurement and
evaluation of vibration, vibroacoustic diagnostics. Thermodynamic method.
3 The methods of technical diagnostics: tribotechnical - tribodiagnostics
degradation of lubricating oil, wear tribodiagnostics of machinery
systems.
4 Reliability of hydraulic components and equipment. Reliability evaluation. Reliability indicators R(t), F(t), f(t), lambda(t).
5 Failures and their classification. Intensity of failures lambda(t). Mean time between failures.
6 Trouble-free operation of systems. Backup. Lifetime and lifetime indicators. Standby and means of achieving of high standby of facilities.
7. Reliability tests. Accelerated tests with increased parameters. Accelerated cycling test. Accelerated test with artificial liquid contamination.
8 Technical Means of diagnostics: distribution. Sensors of quantities:
requirements, metrological characteristics.
9 Basic principles of sensors. Sensors of diagnostic quantities: pressure, flow.
10 Sensors of diagnostic quantities: temperature, path, speed, acceleration,
force, torque.
11 Sensors of speed, noise and vibration. Noise measurement. Calibration of sensors.
12 Multi-sensors and evaluation systems. Diagnostics of hydraulic pumps and rotary hydraulic motors.
13 Diagnostics of linear hydraulic motors, compressors, pneumatic motors, pressure valves, directional valves and other flow elements.
14 Simulation of operation. Diagnostics of hydraulic systems. Monitoring of machines.

Exercise program + individual working of students

Week Refill exercises and seminars
1 Examples of means for technical diagnostics in the department laboratory.
2 Introduction to measurement and evaluation using system Hydrotechnik M 5000 and evaluation program HYDROWIN.
3 Measurement of hydraulic quantities during cavitation using measuring system M 5000 Hydrotechnik.
4 Identification of measuring and evaluating system HYDAC incl. evaluation of measured quantities. Measurement of pressure.
5 Diagnostics of rotary hydraulic motor.
6 Diagnostics of hydraulic pump.
7 Diagnostics of directional valve. Program No. 1, laboratory exercise: (max. 5 points).
8 Program No. 2, laboratory exercise: Diagnostics of hydraulic drive with rotary hydraulic motor by means of measuring system M 5000 Hydrotechnik – time dependence. (max. 5 points).
9 Program No. 3, project. Calculation of intensity of failures lambda(t) for two basic types of failures (random failures and gradually accruing failures). (max. 5 points).
10 Program No. 4. Project of technical diagnostics of a given system. (max. 10 points).
11 Diagnostics of working fluids. Measurement of bulk modulus of liquids
12 Program No. 5, laboratory exercise: Measurement of liquid viscosity by means of programmable Brookfield rotary viscometer. (max. 5 points).
13 Program No. 5, laboratory exercise: Calibration of pressure sensor by means of piston manometer. (max. 5 points). Vibration measurement.
14 Calibration of inductivity path sensor. Credit.

Exam questions:

1 Meaning and tasks of technical diagnostics. Terminology.
2 Basic methods of technical diagnostics. Parametric methods of technical diagnostics. Diagnostic parameters.
3 Vibrodiagnostics. Vibroacoustic diagnostics.
4 Tribotechnical diagnostics - tribodiagnostics of degradation of lubricant oil.
5 Tribotechnical diagnostics - wear tribodiagnostics of machinery
systems.
6 Failures and their classification.
7 Reliability of products and reliability indicators R(t), F(t), f(t), lambda(t).
8 Intensity dependence of failures lambda(t) for random failures and gradually accruing failures. Trouble-free operation of systems.
9 Reliability and reliability indicators. Standby and means of achieving of high standby of facilities.
10 Reliability tests. Accelerated tests with increased parameters, accelerated cycling tests, accelerated tests with artificial liquid contamination.
11 Means of technicaldiagnostics – distribution.
12 Sensors of quantities: requirements, metrological characteristics.
13 Basic physical principles of sensors.
14 Path sensors, speed sensors.
15 Pressure and force sensors.
16 Flow and rpm sensors.
17 Torque sensors. Temperature sensors.
18 Noise and vibration sensors.
19 Multi-sensors and measuring instruments.
20 Calibration of pressure, flow and path sensors.
21 Simulation of operation - Pressure and flow jump.
22 Diagnostics of hydraulic pumps: circuit diagram, measuring principle,
characteristics.
23 Diagnostics of rotary hydraulic motors: circuit diagram, measuring principle,
characteristics.
24 Diagnostics of linear hydraulic motor: circuit diagram, principle
measurement, characteristics.
25 Diagnostics of compressor: circuit diagram, measuring principle, characteristics.
26 Diagnostics of rotary pneumatic motor: circuit diagram, measuring principle, characteristics.
27 Diagnostics of pressure valves: circuit diagram, measuring principle,
characteristics.
28 Diagnostics of distribution valves and check valves: circuit diagram,
measuring principle, characteristics.
29 Thermodynamic methods for efficiency measurement: principles, basic relations.
30 Monitoring of machines.
Recommended or Required Reading
Required Reading:
[1] EXNER, H. et al. Basic Principles and Components of Fluid Technology. Lohr am Main, Germany: Rexroth AG., 1991. 344 p. ISBN 3-8023-0266-4.
[2] GOLDSTEIN, R. J. Fluid Mechanics Measurements. Washington : Hemisphere Publishing Corporation. 1983. 647 p. ISBN 0-89116-244-5.
[1] KOPÁČEK, J. Technická diagnostika hydraulických mechanismů. Praha: SNTL, 1990. 160 s. ISBN 80-03-00308-3.
[2] JANALÍK, J. Měření tekutinových mechanismů. Ostrava : VŠB-TU Ostrava, 1995. 129 s. http://www.338.vsb.cz/PDF/Mereni_tek_mech.pdf
[3] HRUŽÍK, L. Měření veličin v hydraulice s využitím přístroje Hydrotechnik. Ostrava : VŠB-TU Ostrava, 2012. 54 s.
[4] HRUŽÍK, L. Experimentální úlohy v tekutinových mechanizmech. Ostrava: VŠB-TU Ostrava, 2008. 61 s. ISBN 978-80-248-1912-9. Dostupné na:CD-ROM, http://www.338.vsb.cz/PDF/Experimentalniulohyvtekutinovychmechanizmech.pdf.

Recommended Reading:
[1] GÖTZ, W. Hydraulics. Theory and Applications. Ditzingen, Germany: OMEGON, 1998. 291 s. ISBN 3-980-5925-3-7.
[2] HEHN, H. et al. Fluid Power Troubleshooting. New York : Marcel Dekker. 1995. 647 p. ISBN 0-8247-9275-0.
[1] KOPÁČEK, J. Pneumatické mechanismy. Díl I. Ostrava : VŠB-TU Ostrava 1996.
267 s. ISBN 80-7078-306-0.
[2]HAVLÍČEK, J. Provozní spolehlivost strojů. Praha, SZN 1989. 656 s. ISBN 80-209-0029-2.
[3] ZIEGLER, J. Technická diagnostika výrobních zařízení. Skriptum. Ostrava: VŠB-TU Ostrava, 1992. 182 s. ISBN 80-7078-111-4.
[4] VOŠTOVÁ, V.; HELEBRANT, F.; JEŘÁBEK, K. Provoz a údržba strojů. II. část Údržba strojů. Praha: ČVUT Praha, 2002. 124 s. ISBN 80-01-02531-4.
[6] JANOUŠEK, F.; KOZÁK, J.; TARABA, O. Technická diagnostika. Praha: SNTL, 1988. 429 s.
[7] PAVLOK,B. Základní konstrukční celky. Ostrava : VŠB-TU Ostrava, 2008. 41 s. http://www.338.vsb.cz/PDF/zakladni-konstrukcni-celky.pdf

Planned learning activities and teaching methods
Lectures, Tutorials, Experimental work in labs, Other activities
Assesment methods and criteria
Task TitleTask TypeMaximum Number of Points
(Act. for Subtasks)
Minimum Number of Points for Task Passing
Credit and ExaminationCredit and Examination100 (100)51
        CreditCredit35 18
        ExaminationExamination65 25