Applying of Automatic Laser Particle Counter as Technique to Morphology Assessment and Distribution of Wear Particles during Lifetime of Transmission Oils

2015 ◽  
Vol 669 ◽  
pp. 417-425 ◽  
Author(s):  
Marián Kučera ◽  
Zdeněk Aleš ◽  
Jindřich Pavlů ◽  
Michaela Hnilicová
Keyword(s):  
Operating Conditions ◽  
Wear Particles ◽  
Environment Pollution ◽  
Particle Counter ◽  
Important Prerequisite ◽  
Biodegradable Oils ◽  
Transmission Oil ◽  
Technical Issues ◽  
Equipment Wear

Vast part of environment pollution is caused by the lubricants. Lubricants are mostly of mineral origin. They are toxic and not easily biodegradable. Transition to biodegradable oils involves several technical issues. During the operation of machines and equipment wear occurs due to formation of particles that pollute the lubricant fillings. Cleanliness of the oils in lubrication systems is an important prerequisite for maintaining the operating conditions of machines and equipment.The aim of this article is to evaluate distribution of wear particles of tested transmission oil samples via automatic laser particle counter and classifier LaserNet Fines-C which is highly accurate and a fully automated tribotechnical diagnostics device.

Minimum Sampling Time/Volume for Liquid-Borne Particle Counters and Monitors

1997 ◽  
Vol 40 (6) ◽  
pp. 29-34
Author(s):  
Mindi Xu ◽  
Hwa-Chi Wang
Keyword(s):  
Standard Deviation ◽  
Particle Concentration ◽  
Sample Volume ◽  
Average Concentration ◽  
Sampling Time ◽  
Operating Conditions ◽  
Average Particle ◽  
Particle Counter ◽  
Particle Counts ◽  
The Difference

A particle counter is an instrument that measures particles in all the fluid passing through its sensor, and a particle monitor measures particles only in a portion of the fluid. For liquid with an ultralow particle concentration, particles may not disperse uniformly in the liquid. Therefore, the concentrations may vary significantly from measurement to measurement if the sample volume is not large enough. To achieve the same precision, a minimum sampling time or minimum sample volume for a particle instrument needs to be specified. A Poisson distribution was used to describe the distribution of particle counts. Testing included a series of particle concentration measurements. Minimum sampling time or sample volume at a given average concentration with different error levels was determined for selected commercial particle instruments. At the same flow rate, a particle monitor always requires a longer sampling time than a particle counter to achieve a specific precision for a given concentration. The minimum sampling time also varies among instruments because of the difference in sample volume in which the particles are counted. Experiments with a particle monitor have been conducted to thest the changes in average particle concentration and the standard deviation at different operating conditions.

scholarly journals Influence of the Processes Occurring in the Movable Interfaces of the Parts of Transport Machines Under the Action of the Components of the Geomodifier on the Efficiency of Tribotechnologies of Running-in and Recovery

2020 ◽  
pp. 250-265
Author(s):  
Viktor Aulin ◽  
◽  
Sergey Lysenko ◽  
Andriy Grinkiv ◽  
Andriy Chernai ◽  
...  
Keyword(s):  
Nonequilibrium Thermodynamics ◽  
Protective Coatings ◽  
Operating Conditions ◽  
Working Environment ◽  
Physical Processes ◽  
Friction Zone ◽  
Transmission Oil ◽  
Main Components ◽  
Aluminosilicate Mineral ◽  
Degree Of Fragmentation

It is shown that the effectiveness of the implementation of tribotechnologies for running-in and restoration of systems and assemblies of transport machines depends on the preparation of the working environment in which the running-in of tribocouplings of parts takes place. When using a geomodifier to add to engine and transmission oil, it is important to refine the particles of its components and obtain special properties of their surfaces. The properties of the main components of the KGMT-1 geomodifier: SiO2, MgO, Al2O3, Fe2O3 are considered. Their activation during grinding and feeding into the friction zone is substantiated. The change in the size of the particles of the components of the geomodifier on the duration of the test under various operating conditions and within the limits of the strength intervals was investigated. The course of various physical processes according to nonequilibrium thermodynamics and the realization of states and processes of self-organization are considered. It was found that, depending on the degree of fragmentation, the particles of the components exhibit different activity, and therefore, different conditions for the formation of protective coatings on the working surfaces of parts and tribomechanical and tribophysical effects on particles are realized. It is shown that the latter manifests itself during the formation of defects, specific surface area, and duration of mechanical activation. It was revealed that for the materials of the KGMT-1 geomodifier components with strongly homeopolar bonds, such as SiO2, SiC, and the aluminosilicate mineral kaolinite, an amorphization process is observed. The influence of the α-Si-k-Si phase transformation in the materials of the KGMT-1 additive on the efficiency of the implementation of tribotechnologies has been determined. It is shown how physical processes in a composite oil cause tribochemical reactions and formation of coatings on the working surfaces of interfaces of parts of systems and aggregates of transport machines.

An Avionics Integrity Program Approach to Preventing Aircraft Electronics Humidity and Moisture Problems

2009 ◽  
Author(s):  
Charles Lide ◽  
Stefan Glista
Keyword(s):  
Development Process ◽  
Test Methods ◽  
Operating Conditions ◽  
Process Improvements ◽  
Standard Procedures ◽  
Technical Issues ◽  
Verification Process ◽  
Improved Methods ◽  
Moisture Resistant ◽  
Field Failure

Analysis of the causes of airborne electronics field failures indicates that humidity, moisture, and corrosion are significant contributors to the total field failure population. In spite of this fact, analysis methods, test methods and standard procedures to address these problems are less mature than those for other electronics failure mechanisms such as low and high cycle fatigue. An Avionics Integrity Program (AVIP) approach to address humidity and moisture issues is outlined. Programmatic and technical issues associated with achieving humidity and moisture resistance are discussed. The paper focuses on the steps to be taken at each stage of the development and verification process to reduce the probability of moisture related problems escaping to later stages of development and verification. Design and development process improvements are discussed along with areas of need for improved methods. Sources of moisture including the influence of cooling interface temperatures are presented along with mitigations to moisture sources. Examples of moisture-related failures are discussed along with corrective actions to the electronic equipment. Design criteria to prevent moisture-related failures and achieve a moisture-resistant design are presented. Limitations of humidity test methods are covered along with suggested improvements to increase realism of testing to match the severe environmental and operating conditions. Finally, field life management moisture screening is proposed.

Wear Measurement of a Large Hydraulic Fluid Power Pump Using Radioactive Tracer Wear Technology

2003 ◽  
Author(s):  
Martin B. Treuhaft ◽  
Suzanne A. Timmons ◽  
Douglas C. Eberle ◽  
Glenn R. Wendel
Keyword(s):  
Steady State ◽  
Wear Rate ◽  
Internal Combustion Engines ◽  
Gamma Ray ◽  
Radioactive Tracer ◽  
Operating Conditions ◽  
Contamination Level ◽  
Wear Particles ◽  
Hydraulic Pump ◽  
Wear Measurement

Real-time wear measurement is possible in fluid lubricated components utilizing radioactive tracer technology (RATT). This technology has been applied to internal combustion engines since the 1950’s, but has only recently been applied to hydraulic components. This paper presents the application of radioactive tracer technology to measure wear rate of pistons and slippers in a large variable displacement, high pressure, axial piston pump under various operating conditions. To apply this technology, new piston and slipper assemblies were exposed to thermal neutrons in a nuclear reactor to produce characteristic radionuclides (isotopes) in the slippers and pistons. These isotopes act as tracers, which when worn off in an operating pump can be measured by monitoring the gamma-ray activity in the circulating fluid. The accumlation of wear particles in the unfiltered circulation loop is monitored continuously as the pump is operated under various transient and steady state conditions. The steady state wear rate is determined by the rate of accumulation of radioactive wear particles in the loop over a period of time, usually less than a few hours. This first time application of RATT for wear analysis in a large hydraulic pump has shown positive results. This technology can be applied to determine wear sensitivity of hydraulic pump parts for an endless array of factors, such as speed, pressure, displacement, temperature, contamination level and composition, and duty cycle. Break-in, start-up, and transient wear affects can also be observed. Comparisons can also be made between the wear of different design features and materials.

scholarly journals THE EFFICIENCY OF COMBINED-CYCLE CHP PLANT WITH VARIABLE ELECTRIC LOADS, TAKING INTO ACCOUNT THE WEAR AND TEAR OF EQUIPMENT

2018 ◽  
Vol 20 (7-8) ◽  
pp. 10-22 ◽  
Author(s):  
R. Z. Aminov ◽  
M. V. Garievsky
Keyword(s):  
Economic Efficiency ◽  
Economic Performance ◽  
Combined Cycle ◽  
Operating Conditions ◽  
Electrical Load ◽  
Optimal Load ◽  
Wear And Tear ◽  
Equipment Wear ◽  
Electric Loads

The economic efficiency of attracting CHPPs to cover the variable zone of daily electrical load schedules was investigated. The estimation of resource and economic performance of combined -cycle HPPs using the example of PGU-450T taking into account equipment wear under different operating conditions in the daily and weekly sections and different composition of the operating equipment has been performed and optimal load regimes have been determined.

Modeling and Analysis of the Hydraulic System for Oil Budget in an Automotive Transmission

2008 ◽  
Author(s):  
Hsu-Chiang Miao ◽  
Zongxuan Sun ◽  
Jonathan Fair ◽  
Joshua Lehrmann ◽  
Samuel Harbin
Keyword(s):  
Fuel Economy ◽  
Hydraulic System ◽  
Dynamic Performance ◽  
Operating Conditions ◽  
Modeling And Analysis ◽  
Budget Analysis ◽  
Automotive Transmission ◽  
Transmission Oil ◽  
Dynamic Operating ◽  
Cooling And Lubrication

Many automotive transmissions, including automatic and hybrid transmissions, employ electro-hydraulics for gear shift, system cooling, and lubrication. Transmission oil budget refers to the process of dynamically distributing pressurized fluid from the pump into the sub-systems of the transmission. The oil budget will ultimately determine the transmission pump size and directly impact vehicle fuel economy. It will further affect the dynamic performance of the transmission. Due to large number of components, complex hydraulic circuits, and dynamic operating conditions, estimating transmission oil budget is extremely complex. To obtain a precise oil budget, we need to not only model each hydraulic component accurately, but also analyze the flow requirement in a dynamic fashion. This paper presents the modeling of the transmission hydraulic system and its application for oil budget analysis.

scholarly journals Morphology Analysis of Friction Particles Generated in Tractor Transmission Oils

2017 ◽  
Vol 20 (3) ◽  
pp. 57-62
Author(s):  
Marián Kučera ◽  
Zdeněk Aleš
Keyword(s):  
Dynamic Equilibrium ◽  
Equilibrium Concentration ◽  
Mineral Oil ◽  
Wear Particles ◽  
Term Experiment ◽  
Transmission Oil ◽  
Measurement Results ◽  
Long Term Experiment ◽  
Ideal Tool

AbstractThe aim of the study was the examination of the morphological and compositional attributes of wear particles of tested universal tractor transmission oil (UTTO) samples by means of automatic particle counter and classifier LaserNetFinesTM-C, which is an ideal tool to establish the dynamic equilibrium concentration and hence to set the alarm limits for any type of machine. Such limits can be based on wear type and particle size ranges. The samples of two UTTO (mineral oil and biodegradable fully synthetic oil) were taken from the rear gearboxes of the wheel tractor during a long-term experiment. The measurement results showed that there was faster increase in the particle wear of mineral oil in comparison to biodegradable transmission oil. Considering the increase in the percentage of particles over 20 μm, the biodegradable oil seems to be more favourable for usage. Regardless of this, it can be concluded that the biodegradable oil is equivalent to petroleum-based oils.

scholarly journals FEATURES OF THE TECHNICAL OBJECTS CONTROL WITH REGISTRATION THEIR WEAR-OUT

2018 ◽  
Vol 10 (4) ◽  
pp. 28-31
Author(s):  
S Voinova
Keyword(s):  
Maximum Level ◽  
Operating Conditions ◽  
Theory And Practice ◽  
Technical Object ◽  
Term Operation ◽  
Automatic Control Systems ◽  
Current State ◽  
Technological Efficiency ◽  
Complex Automation ◽  
Equipment Wear

The operation of technical objects is subject to the regulatory conditions established by their manufacturer. Regime of regulatory conditions keeping needs to be controlled. A new technical object at the time of commissioning has an initial, maximum level of technological efficiency of operation, including ecological, economic and general technical components, and has an initial, complete working capacity resource too. During operation, the technical object wears-out, its technological efficiency is reduced. In accordance with the international standard and the standard of Ukraine, a technical object that has exhausted a resource is subject to decommissioning and replacement with a new technical object, since at a level of technological efficiency that is less than the minimum, the use of technical object is inexpedient. However, in the current difficult economic conditions in Ukraine, the replacement of worn-out equipment with a new one is impracticable. Further use of worn-out equipment is inevitable. To control a worn out object, complex automation is required. The technical object is studied in this direction from three positions. The first is to study the process of wearing-out. The second is the prediction of wearing-out dynamics. The third is the object control in the process of its wearing-out. The development of the theory and practice of worn out objects automating leads to the formulation of new tasks. With long-term operation of the equipment, it is necessary to periodically adjust its characteristics. It is necessary to create adaptive automatic control systems that take into account the degree of equipment wear-out and conditions of its operation. It is important to establish the patterns of influence of the current state of the equipment and the operating conditions on its residual resource. A productive way to increase the efficiency of worn-out equipment is its renovation by implementing measures that increase the level of efficiency of the most worn-out elements of technical objects. The technical objects control with registration their wear-out will ensure compliance with the regulations for their operation.

Cathodoluminescence of Catalyst Crystallites

1982 ◽  
Vol 40 ◽  
pp. 664-665
Author(s):  
E.D. Boyes ◽  
P.L. Gai ◽  
D.B. Darby ◽  
C. Warwick
Keyword(s):  
Defect Density ◽  
Chemical Properties ◽  
Operating Conditions ◽  
Semiconductor Materials ◽  
Environmental Cell ◽  
High Resolution Structure ◽  
Commercially Important ◽  
Crystallographic Defects ◽  
Resolution Structure

The extended crystallographic defects introduced into some oxide catalysts under operating conditions may be a consequence and accommodation of the changes produced by the catalytic activity, rather than always being the origin of the reactivity. Operation without such defects has been established for the commercially important tellurium molybdate system. in addition it is clear that the point defect density and the electronic structure can both have a significant influence on the chemical properties and hence on the effectiveness (activity and selectivity) of the material as a catalyst. SEM/probe techniques more commonly applied to semiconductor materials, have been investigated to supplement the information obtained from in-situ environmental cell HVEM, ultra-high resolution structure imaging and more conventional AEM and EPMA chemical microanalysis.

Comparison of Deterministic and Linear Cosine Spatial Filtering of Transmission Electron Micrographs

1972 ◽  
Vol 30 ◽  
pp. 596-597
Author(s):  
David A. Ansley
Keyword(s):  
Spherical Aberration ◽  
Focal Length ◽  
Chromatic Aberration ◽  
Spatial Filter ◽  
Operating Conditions ◽  
Objective Lens ◽  
List Type ◽  
Spatial Filters ◽  
Transmission Electron ◽  
Wide Range

The coherence of the electron flux of a transmission electron microscope (TEM) limits the direct application of deconvolution techniques which have been used successfully on unmanned spacecraft programs. The theory assumes noncoherent illumination. Deconvolution of a TEM micrograph will, therefore, in general produce spurious detail rather than improved resolution.A primary goal of our research is to study the performance of several types of linear spatial filters as a function of specimen contrast, phase, and coherence. We have, therefore, developed a one-dimensional analysis and plotting program to simulate a wide 'range of operating conditions of the TEM, including adjustment of the:(1) Specimen amplitude, phase, and separation(2) Illumination wavelength, half-angle, and tilt(3) Objective lens focal length and aperture width(4) Spherical aberration, defocus, and chromatic aberration focus shift(5) Detector gamma, additive, and multiplicative noise constants(6) Type of spatial filter: linear cosine, linear sine, or deterministic

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