scholarly journals Experimental and Numerical Studies of Tool Wear Processes in the Nibbling Process

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 107
Author(s):  
Łukasz Bohdal ◽  
Leon Kukiełka ◽  
Radosław Patyk ◽  
Katarzyna Kośka ◽  
Jarosław Chodór ◽  
...  
Keyword(s):  
Abrasive Wear ◽  
Experimental Studies ◽  
Fold Increase ◽  
Cutting Edge ◽  
Qualitative Assessment ◽  
Fatigue Wear ◽  
Wear Process ◽  
Numerical Studies ◽  
Technological Quality

The work concerns an analysis of the wear mechanisms of punches in the nibbling process. The nibbling process is the multiple punching of holes or external contours using circular punches, the diameter of which is much smaller than the size of the punched shapes. Analytical, numerical and experimental studies were carried out. In the analytical solution, formulas for determining the pressures in the contact zone were developed, thus enabling a simple estimation of the designed nibbling tools. In numerical studies, the influence of the punch rounding radius on the fatigue wear was investigated. It has been shown that the change in the punch cutting edge radius from r = 0 mm to r = 0.5 mm enables a seven-fold increase in the fatigue wear resistance. It was found that the change in the punch cutting edge rounding radius has an impact on the quality of the product (the greater the radius r, the worse the technological quality of the product). In experimental studies, the abrasive wear process was primarily investigated. For this purpose, the nibbling process was tested on S235JR + AR steel sheets with tools made of NC11LV/1.2379 steel without any coating and with an AlCrTiN layer. It was found that the special AlCrTiN layer used allowed for an increase in the resistance to abrasive wear, and thus increased the service life by approx. three times. The last element of the work is an assessment of the technological quality of the product after nibbling depending on the degree and type of stamp wear (quantitative and qualitative assessment).

Wear Performance of GCr15 Friction Pairs with Effect of Initial Radial Micro-Grooves

2019 ◽  
Vol 11 (1) ◽  
pp. 56-61
Author(s):  
Wei Yuan ◽  
Shengkai Mei ◽  
Song Li ◽  
Zhiwen Wang ◽  
Jie Yu ◽  
...  
Keyword(s):  
Wear Rate ◽  
Abrasive Wear ◽  
Electrical Discharge Machining ◽  
Friction Pair ◽  
Wear Volume ◽  
Fatigue Wear ◽  
Wear Performance ◽  
Wear Process ◽  
Groove Test ◽  
On Line

Background: Grooves may inevitably occur on the surface of the friction pair caused by severe wear or residual stress, which will play an important role on the reliability of machine parts during operation. Objective: The effect of the micro-grooves perpendicular to sliding direction on the wear performance of the friction pairs should be studied. Method: Micro-grooves can be machined on discs of friction pairs using electrical discharge machining. On-line visual ferrograph method was used to monitor the wear process to research the wear rate changing characteristic. Profilemeter and metallurgical microscope were used to observe the wear scars. Results: Comparing to the non-groove test, i) in one-groove test, wear volume and rate were approximate the same, and the wear scar was smooth, ii) when the grooves more than 4, the test running-in stage will be obviously prolonged, particularly for the test with 8 grooves on the disc, the duration of running-in stage is 4 times than that without grooves on specimen, and the wear rate and volume increase significantly, and then decrease with fluctuation, iii) the abrasive wear can be avoid with the debris stagnating in the groove, however, fatigue wear will significantly emerge. Conclusion: Abrasive wear can be avoided and smooth running-in surfaces can be obtained with proper amount of initial radial micro-grooves.

Qualitative assessment of equipment failure cause finding and removal

2018 ◽  
pp. 116-126
Author(s):  
E. A. Vakulin ◽  
A. I. Zayats ◽  
V. A. Beklemeshev ◽  
V. A. Ivashkevich ◽  
V. A. Khazhiev ◽  
...  
Keyword(s):  
Production Condition ◽  
Real Life ◽  
Open Pit Mine ◽  
Qualitative Assessment ◽  
Open Pit ◽  
Quality Level ◽  
Equipment Failure ◽  
Operation Conditions ◽  
Failure Investigation

Investigation of failures is one of the critical activities of mining and haulage equipment operability assurance in mining. Maintaining failure investigation at the required quality level, it is possible to identify provisions, rules and procedures that should be revised or changed, operation conditions that should be improved, additional personnel training, if required, etc. Investigation of failures in mines is under responsibility of machine men and electricians of maintenance and operation services. In reality, factory management and setup for production condition weak concernment of these workers in quality investigation aimed at finding of sources of equipment failures. This article describes real-life results achieved in development and use of maintenance service operation, technology and management monitoring. The requirements are substantiated for quality improvement in failure cause finding and removal in mining and haulage equipment at Chernogorsky open pit mine, SUEK-Khakassia. Causes of the present quality of failure investigation by machine men of Chernogorsky Repair and Engineering Works and Chernogorsky open pit mine are revealed. The proposed recommended practices will improve quality of mining and haulage equipment failure investigation.

Considerations of the technological quality assessment of sugarbeet

2011 ◽  
pp. 85-89 ◽  
Author(s):  
Giorgio Pezzi
Keyword(s):  
Quality Parameters ◽  
Northern Italy ◽  
Glucose Content ◽  
Long Term Storage ◽  
Interesting Correlation ◽  
Technological Quality ◽  
Thick Juice

No real improvement in the technological quality of beet has been recorded over the last 15 years in Northern Italy. Among the possible explanations for the quality stagnation is that the traditional formulae cannot correctly differentiate between sugarbeet varieties which produce thick juice of very high purity. This seems to be connected with the role of potassium. The use of a standard purification procedure gives reliable and accurate data which is immediately comparable with the factory data. Research projects on medium/long term storage are currently being performed by Co.Pro.B., Italy, in cooperation with Syngenta and Beta. Up to now the results have shown that storage of sugarbeet in autumn time in northern Italy is possible provided that suitable varieties and proper handling of the roots are employed. Results obtained in the storage trials are reported. Correlations have been found between quality parameters (purity, color and lime salts) of the purified juice with the glucose content of the raw juice. An interesting correlation is reported between purified juice purity and raw juice purity.

The system of indicators of the quality of the carbon-carbon composite materials and technologies of their production

2018 ◽  
pp. 127-132
Author(s):  
T. N. Antipova ◽  
D. S. Shiroyan
Keyword(s):  
Composite Material ◽  
Low Cost ◽  
Experimental Studies ◽  
Carbon Matrix ◽  
Carbon Composite ◽  
Optimal Number ◽  
Laboratory Equipment ◽  
Carbon Composite Material ◽  
Carbon Composite Materials

The system of indicators of quality of carbon-carbon composite material and technological operations of its production is proved in the work. As a result of the experimental studies, with respect to the existing laboratory equipment, the optimal number of cycles of saturation of the reinforcing frame with a carbon matrix is determined. It was found that to obtain a carbon-carbon composite material with a low cost and the required quality indicators, it is necessary to introduce additional parameters of the pitch melt at the impregnation stage.

scholarly journals Quality of beef diaphragm meat in naturally occurring Sarcocystic infection in cattle

2018 ◽  
Vol 36 (No. 5) ◽  
pp. 378-385
Author(s):  
Vytautas Januskevicius ◽  
Grazina Januskeviciene ◽  
Gintare Zaborskiene
Keyword(s):  
Meat Quality ◽  
Harmful Effect ◽  
Coliform Bacteria ◽  
E Coli ◽  
Noticeable Increase ◽  
Physico Chemical ◽  
Infected Meat ◽  
Technological Quality ◽  
Meat Samples

The aim of this study was to investigate the possible harmful effect of Sarcocystis parasites on bovine diaphragm meat quality. Meat samples were collected from 120 bulls aged 20–24 months. Meat quality was investigated using microbiological and physico-chemical (RP-HPLC, GC) methods 48 hours after slaughter. Sarcocystis infection was associated with increased fat content, lightness L* and drip loss, and decreased ash and protein percentages. Infection also had a significant effect on the amount of amino acids (AAs), which slowly decreased as the number of sarcocysts increased. The total amount of AAs correlated with glutamic acid content (R = 0.966, P &lt; 0.05). Heavily infected samples contained significantly lower amounts of putrescine, histamine, spermine and spermidine (P &lt; 0.05) and<br /> a noticeable increase in the total count of aerobic microorganisms, but no change in the numbers of E. coli and coliform bacteria in comparison with no infected samples. Sarcocysts in beef diaphragms did not cause serious changes in the technological quality of the meat, but the biological quality of infected meat was reduced.  

scholarly journals Effect of the Application Date of Fertilizer Containing Silicon and Potassium on the Yield and Technological Quality of Sugar Beet Roots

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 370
Author(s):  
Arkadiusz Artyszak ◽  
Dariusz Gozdowski ◽  
Alicja Siuda
Keyword(s):  
Sugar Beet ◽  
Foliar Application ◽  
Plant Protection ◽  
Plant Protection Products ◽  
Water Shortage ◽  
The European Union ◽  
Yield Increase ◽  
Time Of Application ◽  
Technological Quality

Water shortage and drought are a growing problem in Europe. Therefore, effective methods for limiting its effects are necessary. At the same time, the “field to fork” strategy adopted by the European Commission aims to achieve a significant reduction in the use of plant protection products and fertilizers in the European Union. In an experiment conducted in 2018–2020, the effect of the method of foliar fertilization containing silicon and potassium on the yield and technological quality of sugar beet roots was assessed. The fertilizer was used in seven combinations, differing in the number and time of application. The best results were obtained by treating plants during drought stress. The better soil moisture for the plants, the smaller the pure sugar yield increase was observed. It is difficult to clearly state which combination of silicon and potassium foliar application is optimal, as their effects do not differ greatly.

scholarly journals Sterilization regret in India: Is quality of care a matter of concern?

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Anjali Bansal ◽  
Laxmi Kant Dwivedi
Keyword(s):  
Quality Of Care ◽  
Family Planning ◽  
Health Facility ◽  
Fold Increase ◽  
Well Being ◽  
Poor Quality ◽  
Public Health Facility ◽  
The Family ◽  
Planning Methods

Abstract Background According to United Nations, 19% of females in the world relied only on the permanent method of family planning, with 37% in India according to NFHS-4. Limited studies tried to measure the sterilization regret, and its correlated factors. The study tried to explore the trend of sterilization regret in India from 1992 to 2015 and to elicit the determining effects of various factors on sterilization regret, especially in context to perceived quality of care in the sterilization operations and type of providers. Data and methods The pooled data from NFHS-1, NFHS-3 and NFHS-4 was used to explore the regret by creating interaction between time and all the predictors. Predicted probabilities were calculated to show the trend of sterilization regret amounting to quality of care, type of health provider at the three time periods. Results The sterilization regret was increased from 5 % in NFHS-1 to 7 % in NFHS-4. According to NFHS-4, for those whose sterilization was performed in private health facility the regret was found to be less (OR-0.937; 95% CI- (0.882–0.996)) compared to public health facility. Also, the results show a two-fold increase in regret when women reported bad quality of care. The results from predicted probabilities provide enough evidence that the regret due to bad quality of care in sterilization operation had increased with each subsequent round of NFHS. Conclusion Many socio-economic and demographic factors have influenced the regret, but the poor quality of care contributed maximum to the regret from 1992 to 2015. The health facilities have seriously strayed from improving the health and well-being of women in providing the family planning methods. In addition, to public facilities, the regret amounting to private facilities have also increased from NFHS-1 to 4. The quality of care provided in the family planning operation should be standardized in every hospital to strengthen the health systems in the country. The couple should be motivated to adopt more of spacing methods.

Automated Insulin Delivery Systems: Today, Tomorrow and User Requirements

2021 ◽  
pp. 193229682110299
Author(s):  
Marga Giménez ◽  
Ignacio Conget ◽  
Nick Oliver
Keyword(s):  
Lived Experience ◽  
Diabetes Management ◽  
Real Life ◽  
Insulin Delivery ◽  
Qualitative Assessment ◽  
Management Tool ◽  
Diabetes Distress ◽  
Glycemic Targets

Automated insulin delivery (AID) is the most recent advance in type 1 diabetes (T1D) management. It has the potential to achieve glycemic targets without disabling hypoglycemia, to improve quality of life and reduce diabetes distress and burden associated with self-management. Several AID systems are currently licensed for use by people with T1D in Europe, United States, and the rest of the world. Despite AID becoming a reality in routine clinical practice over the last few years, the commercially hybrid AID and other systems, are still far from a fully optimized automated diabetes management tool. Implementation of AID systems requires education and support of healthcare professionals taking care of people with T1D, as well as users and their families. There is much to do to increase usability, portability, convenience and to reduce the burden associated with the use of the systems. Co-design, involvement of people with lived experience of T1D and robust qualitative assessment is critical to improving the real-world use of AID systems, especially for those who may have greater need. In addition to this, information regarding the psychosocial impact of the use of AID systems in real life is needed. The first commercially available AID systems are not the end of the development journey but are the first step in learning how to optimally automate insulin delivery in a way that is equitably accessible and effective for people living with T1D.

scholarly journals Supranational Assessment of the Quality of Probiotics: Collaborative Initiative between Independent Accredited Testing Laboratories

2021 ◽  
Vol 9 (7) ◽  
pp. 1456
Author(s):  
Jean-Pol Warzée ◽  
Marina Elli ◽  
Abdoulaye Fall ◽  
Daniela Cattivelli ◽  
Jean-Yves François
Keyword(s):  
Daily Basis ◽  
Qualitative Assessment ◽  
Close Collaboration ◽  
Quality Label ◽  
Accredited Laboratories ◽  
Quantitative Analyses ◽  
Quality Of Food ◽  
The Eu

Recent acquisitions about the role of the microbiota in the functioning of the human body make it possible to envisage an increasing use of beneficial microbes, and more particularly of probiotics as well as their metabolites, as nutritional supplements. National and EU authorities are engaged in assuring the safety and quality of food supplements and in defining rules to assess and communicate their efficacy on human health. The quality of probiotics, intended as strains’ identification, viability, and stability over time, is a crucial factor of credibility with consumers and health professionals. Analytical technologies for the quality control of probiotics must also be adapted to new preparations, such as those including new multistrains complex combinations. Accredited laboratories face this relevant challenge on a daily basis. Through its close collaboration with the laboratory commissioned to produce the specifications for its ESLP quality label (identification and quantitative analyses) together with its scientific committee, the ESLP has been focusing on this issue for 10 years. Recently, as part of the internationalization of the ESLP quality label, a new and unique initiative in Europe for the evaluation of the quality of probiotic preparations has been carried out. The collaboration between two accredited laboratories in Belgium and in Italy represented a concrete example of supranational collaboration in the assessment of the quality of probiotic preparations. Results show that both laboratories are in line as expected in terms of performance. Common approaches to the qualitative assessment of probiotic preparations, especially for complex and composite recipes, in terms of number of strains and included substances, should be encouraged and promoted all over the EU.

scholarly journals Qualitative assessment of YouTube videos as a source of patient information for cochlear implant surgery

2021 ◽  
pp. 1-4
Author(s):  
C Thomas ◽  
J Westwood ◽  
G F Butt
Keyword(s):  
Cochlear Implant ◽  
Cochlear Implants ◽  
Qualitative Assessment ◽  
Supplementary Information ◽  
Implant Surgery ◽  
Critical Elements ◽  
Positive Elements ◽  
Cochlear Implant Surgery ◽  
Youtube Videos

Abstract Background YouTube is increasingly used as a source of healthcare information. This study evaluated the quality of videos on YouTube about cochlear implants. Methods YouTube was searched using the phrase ‘cochlear implant’. The first 60 results were screened by two independent reviewers. A modified Discern tool was used to evaluate the quality of each video. Results Forty-seven videos were analysed. The mean overall Discern score was 2.0 out of 5.0. Videos scored higher for describing positive elements such as the benefits of a cochlear implant (mean score of 3.4) and scored lower for negative elements such as the risks of cochlear implant surgery (mean score of 1.3). Conclusion The quality of information regarding cochlear implant surgery on YouTube is highly variable. These results demonstrated a bias towards the positive attributes of cochlear implants, with little mention of the risks or uncertainty involved. Although videos may be useful as supplementary information, critical elements required to make an informed decision are lacking. This is of particular importance when patients are considering surgery.

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