scholarly journals Quantitative Measuring Analysis Method and Mechanism of Wear Particle Settlement

2021 ◽  
Vol 252 ◽  
pp. 03037
Author(s):  
Kaituo Zhang ◽  
Zhiyong Lv
Keyword(s):  
Specific Gravity ◽  
Magnetic Induction ◽  
Wear Particle ◽  
Lubricating Oil ◽  
Precipitation Process ◽  
Wear Particles ◽  
Analysis Method ◽  
Abrasive Particles ◽  
Initial Stage ◽  
Precipitation Analysis

The size and distribution of wear particle in lubricating oil, as important numerical information available in ferrography, is one of the key indexes in wear diagnosis. In this paper, a new method for measuring the size and distribution of abrasive particles is proposed. First, all the abrasive fluid is left standing until all the abrasive particles are precipitated to the bottom. Then, the measuring container is inverted and the whole precipitation process of abrasive particles is recorded by magnetic induction instrument. And according to the precipitation analysis of the wear particle, the following results were obtained:1) At the initial stage of the particle settlement, the gravity, the buoyancy and the drag force of the oil achieve balance quickly, the time and distance of the wear particle moving at a constant velocity can be neglected. 2) The settling velocity is related to the diameter and specific gravity of the wear particle as well as the specific gravity and viscosity of the oil, the distribution of the wear particle is proportional to the square of the diameter of the particle, using the magnetic induction technology, the distribution of particle can be measured by settling time for different sizes of wear particles. 3) Measure the wear particle oil directly, there are different sizes of particles settlement in the bottom at the same time, which causes the difficulty in identifying the size of the particle settlement. The particle should be settled first, and then inverted, settling the particle in accordance with the order from large to small, which facilitates the measurement of different sizes of the particles, different times correspond to different sizes of the particles. 4) The bigger the particle is, the more accurate the measurement and counting is, the smaller the particle is, the bigger the error is.

scholarly journals A Lubricating Oil Condition Monitoring System Based on Wear Particle Kinematic Analysis in Microfluid for Intelligent Aeroengine

Micromachines ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 748
Author(s):  
Zhenzhen Liu ◽  
Yan Liu ◽  
Hongfu Zuo ◽  
Han Wang ◽  
Hang Fei
Keyword(s):  
Condition Monitoring ◽  
Kinematic Analysis ◽  
Oil Quality ◽  
Particle Diameter ◽  
Wear Particle ◽  
Lubricating Oil ◽  
Wear Particles ◽  
Oil Viscosity ◽  
Monitoring Technology ◽  
Oil Monitoring

Lubricating oil monitoring technology is a commonly used method in aeroengine condition monitoring, which includes particle counting technology, as well as spectral and ferrography technology in offline monitoring. However, these technologies only analyze the characteristics of wear particles and rely on physical and chemical analysis techniques to monitor the oil quality. In order to further advance offline monitoring technology, this paper explores the potential role of differences in wear particle kinematic characteristics in recognizing changes in wear particle diameter and oil viscosity. Firstly, a kinematic force analysis of the wear particles in the microfluid was carried out. Accordingly, a microfluidic channel conducive to observing the movement characteristics of particles was designed. Then, the wear particle kinematic analysis system (WKAS) was designed and fabricated. Secondly, a real-time tracking velocity measurement algorithm was developed by using the Gaussian mixture model (GMM) and the blob-tracking algorithm. Lastly, the WKAS was applied to a pin–disc tester, and the experimental results show that there is a corresponding relationship between the velocity of the particles and their diameter and the oil viscosity. Therefore, WKAS provides a new research idea for intelligent aeroengine lubricating oil monitoring technology. Future work is needed to establish a quantitative relationship between wear particle velocity and particle diameter, density, and oil viscosity.

scholarly journals A New Transfer Learning Ensemble Model with New Training Methods for Gear Wear Particle Recognition

2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Chunhua Zhao ◽  
zhangwen Lin ◽  
Jinling Tan ◽  
Hengxing Hu ◽  
Qian Li
Keyword(s):  
Transfer Learning ◽  
Wear Particle ◽  
Experimental Results ◽  
The Other ◽  
Particle Identification ◽  
Lubricating Oil ◽  
Support Vector ◽  
Training Methods ◽  
Wear Particles ◽  
Feature Expression

Aiming at solving the acquisition problems of wear particle data of large-modulus gear teeth and few training datasets, an integrated model of LCNNE based on transfer learning is proposed in this paper. Firstly, the wear particles are diagnosed and classified by connecting a new joint loss function and two pretrained models VGG19 and GoogLeNet. Subsequently, the wear particles in gearbox lubricating oil are chosen as the experimental object to make a comparison. Compared with the other four models’ experimental results, the model superiority in wear particle identification and classification is verified. Taking five models as feature extractors and support vector machines as classifiers, the experimental results and comparative analysis reveal that the LCNNE model is better than the other four models because its feature expression ability is stronger than that of the other four models.

scholarly journals The construction, development and evaluation of a portable ferro- precipitator

1994 ◽  
Author(s):  
◽  
Ivan Sunjka
Keyword(s):  
Particle Morphology ◽  
Wear Particle ◽  
Particle Analysis ◽  
Spectrometric Method ◽  
Spectrometric Analysis ◽  
Wear Particles ◽  
Engine Test ◽  
Analysis Method ◽  
Depth Study ◽  
The Cost

This dissertation is concerned with the construction of the locally developed Ferro-precipitator which can be utilised outside a laboratory environment. The American developed Ferrograph machine, besides being expensive (R42 000 + GST in 1984), can only be used inside a dust free, temperature controlled room. As lubricants in machinery moving parts play an important role in their performance and durability many methods of evaluating the health of machines have been devised, but none by themselves can give a complete picture of what is happening inside the machine. Various methods of oil analysis have been studied in this dissertation for comparison and/or complementary purposes, so as to establish the role of the Ferro-precipitator in the context mentioned. Spectrometric, Debris and Radio Tracer methods are based on quantitative aspects of wear particle analysis, whereas the Magnetic Plug method shows visibly large wear particles in the very high wear pattern range. A further aspect to consider is the fact that the Spectrometric analysis method, which is the most common and comprehensive method available in South Africa, is laboratory orientated. This means that an oil sample has to be taken from a machine and then sent to a laboatory for analysis. Besides being time consuming from the time the samples are taken to the time when the results are known, the Spectrometric analysis method is also very expensive. The Ferro-precipitator that has been developed, is sensitive to particle size and to the rate at which these particles are generated. This is due to the phenomenon that a varying magnetic field strength will attract different size ferrous particles accordingly. This concept was validated by manufacturing ferrous particles of various sizes, firstly by grinding and secondly by sieving. These particles, in both cases, were passed through the Ferro-precipitator in a medium of oil, and graphs of density versus distance along the slide were plotted. The graphs showed distinct variations between particle sizes. The manufactured particles were also statistically evaluated by establishing the correlation between the machined and/or the sieved particles to the optically measured particles. The sensitivity of the Ferro-precipitator was further demonstrated by comparing results obtained from an engine test carried out under controlled conditions using the Spectrometric method. If developed further, the Ferro-precipitator .could, be used in the field, which would eliminate the time lost due to samples being sent ot a laboratory. Also the cost of the machine would be a fraction of the price of the Ferrograph and/or the Spectrometer. An in-depth study of particle morphology can be carried out on the wear particles deposited on the slide, with the aid of a Scanning Electron microscope using its X-Ray attachment. The potential for such a study was demonstrated on the engine test performed for this dissertation.

Fault diagnosis through Ferrography (Wear Particle Analysis)

2021 ◽  
pp. 303-322
Author(s):  
Anadi Sinha
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Wear Particle ◽  
Stage Ii ◽  
Lubricating Oil ◽  
Particle Analysis ◽  
Wear Particle Analysis ◽  
Analysis Technique ◽  
Detection And Diagnosis

The purpose of Plant Predictive Maintenance (PDM) programme is to improve Reliability of machineries through early detection and diagnosis of equipment problems, and degradation prior to equipment failure. Ferrography (Wear Particle Analysis) is one of the PDM techniques which allows detection, identification and evaluation of the degradation at the very incipient stage so that degradation is timely attended and mitigatory actions initiated. Ferrography is a Wear Particle Analysis technique based upon systematic collection and analysis of sample of lubricating oil from rotating and reciprocating machines. Ferrography analysis is conducted in 2 phases: Stage I – Quantitative, and Stage II – Qualitative. After Stage II analysis, recommendation is issued based on wear rating (Normal, Marginal, or Critical) so that operator can take timely action. Presently, 21 Nuclear Power Plants are operational in India and Forced Shutdown is a very costly affair. Lube oil of around 60 equipment from Indian Nuclear Power Plants is examined quarterly for Ferrography analysis, and failure of several equipment is avoided due to timely action. This paper will elaborate on the basic principles of Ferrography, and how systematic implementation of Ferrography has helped in avoiding forced failure of equipment, and hence prevent Forced Shutdown.

Brake Wear Particle Size and Shape Analysis of Non-Asbestos Organic (NAO) and Semi Metallic Brake Pad

2014 ◽  
Vol 71 (2) ◽  
Author(s):  
Hussain, S. ◽  
M.K Abdul Hamid ◽  
A.R Mat Lazim ◽  
A.R. Abu Bakar
Keyword(s):  
Particle Size ◽  
Wear Particle ◽  
Brake Disc ◽  
Wear Particles ◽  
Brake Pad ◽  
Brake Pads ◽  
Size And Shape ◽  
Brake Wear Particles ◽  
Brake Wear ◽  
Particle Size And Shape

Brake wear particles resulting from friction between the brake pad and disc are common in brake system. In this work brake wear particles were analyzed based on the size and shape to investigate the effects of speed and load applied to the generation of brake wear particles. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) was used to identify the size, shape and element compositions of these particles. Two types of brake pads were studied which are non-asbestos organic and semi metallic brake pads. Results showed that the size and shape of the particles generatedvary significantly depending on the applied brake load, and less significantly on brake disc speed. The wear particle becomes bigger with increasing applied brake pressure. The wear particle size varies from 300 nm to 600 µm, and contained elements such as carbon, oxygen, magnesium, aluminum, sulfur and iron.

scholarly journals Novel biological strategies for treatment of wear particle-induced periprosthetic osteolysis of orthopaedic implants for joint replacement

2014 ◽  
Vol 11 (93) ◽  
pp. 20130962 ◽  
Author(s):  
S. B. Goodman ◽  
E. Gibon ◽  
J. Pajarinen ◽  
T.-H. Lin ◽  
M. Keeney ◽  
...  
Keyword(s):  
Pathologic Fracture ◽  
Wear Particle ◽  
Wear Particles ◽  
Implant Loosening ◽  
Orthopaedic Implants ◽  
Periprosthetic Osteolysis ◽  
Joint Replacements ◽  
Local Inhibition ◽  
Tissue Healing ◽  
Chronic Inflammatory Reaction

Wear particles and by-products from joint replacements and other orthopaedic implants may result in a local chronic inflammatory and foreign body reaction. This may lead to persistent synovitis resulting in joint pain and swelling, periprosthetic osteolysis, implant loosening and pathologic fracture. Strategies to modulate the adverse effects of wear debris may improve the function and longevity of joint replacements and other orthopaedic implants, potentially delaying or avoiding complex revision surgical procedures. Three novel biological strategies to mitigate the chronic inflammatory reaction to orthopaedic wear particles are reported. These include (i) interference with systemic macrophage trafficking to the local implant site, (ii) modulation of macrophages from an M1 (pro-inflammatory) to an M2 (anti-inflammatory, pro-tissue healing) phenotype in the periprosthetic tissues, and (iii) local inhibition of the transcription factor nuclear factor kappa B (NF-κB) by delivery of an NF-κB decoy oligodeoxynucleotide, thereby interfering with the production of pro-inflammatory mediators. These three approaches have been shown to be viable strategies for mitigating the undesirable effects of wear particles in preclinical studies. Targeted local delivery of specific biologics may potentially extend the lifetime of orthopaedic implants.

scholarly journals A simple method of suspending implant wear particles for more physiological modelling of cell-particle interactions in vitro

2021 ◽  
Author(s):  
Christine Poon
Keyword(s):  
Wear Debris ◽  
Culture Media ◽  
Polymeric Materials ◽  
Wear Particle ◽  
Physicochemical Characteristics ◽  
Wear Particles ◽  
Simple Method ◽  
Implant Wear

AbstractArthroplasty implants e.g. hip, knee, spinal disc sustain relatively high compressive loading and friction wear, which lead to the formation of wear particles or debris between articulating surfaces. Despite advances in orthopaedic materials and surface treatments, the production of wear debris from any part of a joint arthroplasty implant is currently unavoidable. Implant wear debris induces host immune responses and inflammation, which causes patient pain and ultimately implant failure through progressive inflammation-mediated osteolysis and implant loosening, where the severity and rate of periprosthetic osteolysis depends on the material and physicochemical characteristics of the wear particles. Evaluating the cytotoxicity of implant wear particles is important for regulatory approved clinical application of arthroplasty implants, as is the study of cell-particle response pathways. However, the wear particles of polymeric materials commonly used for arthroplasty implants tend to float when placed in culture media, which limits their contact with cell cultures. This study reports a simple means of suspending wear particles in liquid medium using sodium carboxymethyl cellulose (NaCMC) to provide a more realistic proxy of the interaction between cells and tissues to wear particles in vivo, which are free-floating in synovial fluid within the joint cavity. Low concentrations of NaCMC dissolved in culture medium were found to be effective for suspending polymeric wear particles. Such suspensions may be used as more physiologically-relevant means for testing cellular responses to implant wear debris, as well as studying the combinative effects of shear and wear particle abrasion on cells in a dynamic culture environments such as perfused tissue-on-chip devices.

Comparison of fecal analysis methods for the detection of Platynosomum fastosum in naturally infected cats

2019 ◽  
Vol 22 (4) ◽  
pp. 395-398 ◽  
Author(s):  
Hilary Eisenbraun ◽  
Adnan Alluwie ◽  
Samantha Connolly ◽  
Rajeev Nair ◽  
Guilherme G Verocai ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Acetate Solution ◽  
Analysis Method ◽  
Toxocara Cati ◽  
Fecal Analysis ◽  
Centrifugation Method ◽  
Triton X ◽  
Total Sediment ◽  
Flotation Solution ◽  
Sugar Flotation

Objectives Diagnosis of Platynosomum fastosum Kossack 1910, a liver fluke of cats, can be challenging, with infections potentially not identified depending on the fecal analysis method used. The aim of this study was to compare three methods for identification of P fastosum eggs in feces. Methods Feces from 50 cats with unknown infection status from a location endemic for P fastosum were analyzed. The methods used included double centrifugation with Sheather’s sugar flotation solution (specific gravity 1.28); the Mini-Parasep (Apacor) flotation kit with ZnSO4 (specific gravity 1.20); and the Mini-Parasep sedimentation kit with Triton X/ethyl acetate solution. Results Thirty-four cats were identified as positive for P fastosum. Of these cats, 33 were identified with the double centrifugation method, 16 with the Mini-Parasep flotation kit and 11 with the Mini-Parasep sedimentation kit. Using the total number of samples identified as positive by at least one method as the true positive, the sensitivity of the methods was 97.1% for double centrifugation, 47.1% for the Mini-Parasep flotation kit and 32.4% for the Mini-Parasep sedimentation kit. Other parasite eggs (eg, Ancylostoma tubaeforme, Trichuris species and Toxocara cati) also were detected more frequently with the double centrifugation method. Conclusions and relevance Of the three methods tested, double centrifugation with Sheather’s sugar flotation solution was the most effective in identifying cats with P fastosum and other helminth eggs in their feces. The lower specific gravity of the flotation solution in the Mini-Parasep flotation kit likely influenced the results. A primary drawback of the Mini-Parasep sedimentation kit was the amount of sediment. While more sediment was examined than recommended in the manufacturer’s instructions, this was still only a small portion of the total sediment. In addition, reading the slides took longer than with the other methods.

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