scholarly journals REGARDING THE QUALITY OF ASSEMBLY OF THE SCREW CONNECTIONS OF THE MOUNTING ASSEMBLY OF BALL BEARINGS

2021 ◽  
Vol 3 (163) ◽  
pp. 12-15
Author(s):  
V. Lus’

Application of method of vibrodiagnostics is based on the presence of cross-correlation dependences of dynamic descriptions of all knots from contact pressure in connection through the change of inflexibility of joints. The change of inflexibility of separate elements causes the change of the resulted inflexibility of knot, and at the same time and characteristic it to dynamic descriptions of the artificially created oscillation field: frequencies and amplitudes of resonance vibrations, indexes of damping, phase correlations. There is a task of determination of method of control of the most responsible technological frame-clamping operations at making of such objects: quality of contact connections, ball-bearing knots, fixing of previous pull of ball-bearings and control of isotropicness, inflexibility and dissipative descriptions of the system of pendant of rotor at all stages of drafting, including in the functional state. The primary objective of this work is research of question of influence of non-perfect resiliency and different inflexibility of the supporting bearings on the dynamic reaction of object at external oscillation excitation, determination of estimation of the different inflexibility bearings, determination of accordance of axial inflexibility of ball-bearings supports, them by a basic value. The dynamic model of knot and certain functions of influence of parameters of the system is considered on high-quality indexes. The dynamic model of precision rotor system (PRS) is investigated. Vibration tests at the stage of assembling the structure of the ORS showed that in the process of assembling the elements change the natural frequencies of the system and the quality factor of the oscillating circuits. The resulted dependences allow giving an estimation degree of non-linearity of resilient description and, as a result, different inflexibility of bearings supports as a result of oscillation researches. The sensitivity functions of the design parameters of the complex press-threaded connection in relation to the vibration dynamic parameters – frequencies and amplitudes of resonant oscillations – do not differ qualitatively from those obtained previously.

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Ning Yu ◽  
ChenHui He ◽  
Gulistan Awuti ◽  
Cheng Zeng ◽  
JianGuo Xing ◽  
...  

In this study, a sensitive, precise, and accurate HPLC-UV method was developed and validated to simultaneously determine the six analytes (luteolin-7-O-β-D-glucuronide, apigenin-7-O-β-D-glucuronide, diosmetin-7-O-β-D-glucuronide, acacetin-7-O-β-D-glucuronide, tilianin, and rosmarinic acid) in Yixin Badiranjibuya Granules, in which five analytes (i.e., luteolin-7-O-β-D-glucuronide, apigenin-7-O-β-D-glucuronide, diosmetin-7-O-β-D-glucuronide, acacetin-7-O-β-D-glucuronide, and rosmarinic acid) were determined for the first time in Yixin Badiranjibuya Granules, the content of tilianin in Yixin Badiranjibuya Granules was reported in other literatures, and the content of tilianin in our work was higher than that of the literature reports. The quality of 11 batch samples from four different manufacturers was evaluated using the proposed determination method. The contents of the six analytes were largely different among samples from various manufacturers. Therefore, this determination method can provide a scientific basis for quality evaluation and control of Yixin Badiranjibuya Granules.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Lin Wen

With the revolution in Internet and digital technology, every organization is adopting digital things to carry out their day-to-day activities. Internet of Things (IoT) is a concept that is used to connect various devices over the Internet to increase the production and quality of service, deliver a huge amount of data in seconds, and automate the processes. IoT implementation in the health sector has changed the typical setup into smart and intelligent setup. With the “smart” and “Intelligent” abilities of IoT devices such as sensors and with the collaboration of humans and computers, physical processes can be monitored and, based on the received data, optimal decisions can ultimately be taken. IoT applications in healthcare will increase flexibility, patient’s care, quality of health, and control of diseases. As the IoT combines various heterogeneous devices and the inappropriate determination of the degree of characteristics for Internet of healthcare (IoH) devices may affect the efficiency of services, this research is carried out with the use of decision support system and application of fuzzy analytic network process (fuzzy ANP) was used for optimal determination of the degree of characteristics for IoH devices based on unique properties which would greatly increase the efficiency of industry. The experimental results are efficient and show the usefulness of the approach.


2021 ◽  
Author(s):  
Ali Mortazavi ◽  
Bakytzhan Osserbay

Abstract The stability graph method of stope design is one of the most widely used methods of stability assessments of stopes in underground polymetallic mines. The primary objective of this work is to introduce a new stability chart, which includes all relevant case histories, and to exclude parameters with uncertainties in the determination of stability number. The modified stability number was used to achieve this goal, and the Extended Mathews database was recalculated and compared with the new stability graph. In this study, a new refined Consolidated stability graph was developed by excluding the entry mining methods data from the Extended graph data, and only the non-entry methods data was used. The applicability of the proposed Consolidated stability chart was demonstrated by an open stope example. The stability for each stope surface was evaluated by a probabilistic approach employing a logistic regression model and the developed Consolidated stability chart. Comparing the stability analysis results with that of other published works of the same example shows that the determined Consolidated chart, in which the entry-method data is excluded, produces a more conservative and safer design. In conclusion, the size and quality of the dataset dictate the reliability of this approach.


2020 ◽  
pp. 136-140
Author(s):  
E.B. Volkov ◽  
S.V. Sitdikova

One of the most important indicators of the inclined vibrating screen is analyzed — the effi ciency of separating rocks by size classes which is infl uenced by many different factors: the angle of inclination of the working body, the shape of the sieve holes, the height of the material supply, etc, these factors determine the probability of passage of particles through the screen lattice. A model is proposed for the selection rational operating and design parameters of the installation, corresponding to the specifi ed criterion of effi ciency and wear resistance.


2013 ◽  
Vol 12 (3) ◽  
pp. 097-104
Author(s):  
Maciej Kumor ◽  
Łukasz Kumor ◽  
Joanna Farmas

Geotechnical assessment of the implementation correctness of a road embankment wide range of issues, among which important selection and control of the quality of the earthworks are extremely significant. The article presents results of in situ tests determining correlations between the depending parameters defined by a static plate – VSS test – E1 and E2, and obtained from the study LFG Dynamic Load Plate. Studies indicate that the determination of the correlation between the parameters characterizing the particle size distribution (Cc, Cu, D10, D20, D30, D60), and the compaction parameters obtained by examining the compaction of sand embankment (Evd, E1, E2, I0) is physically complex and hence extremely difficult. 


2020 ◽  
Vol 896 ◽  
pp. 169-174
Author(s):  
Cristina Ileana Pascu ◽  
Anca Didu ◽  
Stefan Gheorghe

SPC (Statistical Process Control) is one of the Lean Manufacturing techniques, but especially Six Sigma, being a method of improving the quality of the manufacturing process, which allows the identification of errors before their production, with the help of which a process can be supervised and when needed, it is possible to carry out an intervention of regulation, respectively of correction of the process, before being nonconformities. The paper presents a study regarding the use of SPC at a company in the automotive field in order to improve the quality of the manufacturing process for a knuckle. Thus, a number of 25 samples were taken, each sample containing a number of 5 pieces. After sampling, a series of techniques and statistical data were used, respectively diagrams and control sheets, which allowed the determination of the process capability by using MiniTab software.


Author(s):  
Anatolii Spirin ◽  
Igor Tverdokhlib ◽  
Mykhailo Zamriі

The peculiarity of harvesting legumes is the need to process their heap on grater devices with subsequent separation. To improve the technical and economic performance of seed heap processing equipment, it is advisable to combine wiping and separation operations by combining a grater working body and a separating rotating sieve of cylindrical or conical shape. The analysis of influence of geometry of rotary sieve drums allows to define the rational form and parameters of work of the separating device which will provide the necessary quality of seed material. Analysis of the literature on the processes of sieve separation of grain and seed mixtures showed the advantages of centrifugal separators with a rotating sieve surface. Improving the efficiency of separation of mixtures by rotary sieves is achieved by the simultaneous use of centrifugal, Coriolis and gravitational forces. The aim of the study is to increase the efficiency of separation of seed heaps of legumes after treatment with a grater device by determining the trajectory of the seeds along the rotational surfaces. Earlier, the authors developed a grater-separating unit in which a cylindrical perforated drum is used to remove unworn seeds. This design does not use the surface of the sieve effectively enough. To increase the uniformity of the load on the steaming surface of the rotary drum, it is advisable to reduce its area in the direction of seed movement. To do this, use a conical separating surface to reduce the radius of the cone in the direction of movement of the material. When considering the movement of a particle, it is represented as a material point with mass m moving along a conical surface that rotates around a vertical axis. As a result of theoretical researches the dependence which defines time of stay of a particle on a sieve depending on a coordinate (length of a generating cone) is received. A graphical interpretation of this dependence for certain values of design parameters is also presented. As a result of research, it was found that increasing the residence time of the material on the sieve due to the use of a conical surface increases the yield of pure seeds, and also contributes to the uniform loading of the sieve surface, which improves the quality of the source material.


Author(s):  
I. M. Kovbasiuk ◽  
O. B. Martsynkiv ◽  
B. O. Martsynkiv

The analysis of modern studies and field data relating to directional wells casing at the enterprises of “Ukrburgas” drilling company has been carried out in the article. In particular, complications with casing strings, which happened when casing directional wells at these enterprises, data on the non-admission of casing strings to the total depth, a brief description of works aimed at restoring the quality of well casing, are considered. Main reasons of complications, damages and failures during well casing process have been determined. It has been found out that casing string failures mostly happened in the areas of intensive wellbore deviation. The reasons of directional wells poor quality casing taking into account the results of new theoretical, experimental and field research have been systemized. Cases of wells poor quality casing are supposed to be divided into two groups: 1) casing strings damage, 2) non-admission of casing strings to the total depth and violation of string integrity. Each of the groups is classified in accordance with the types of poor casing. The main reason of directional wells poor quality casing are failures caused by wrong casing strength calculations, violation of casing well technology, casing strings wear, mining and geological conditions. The non-admission of the columns to the total depth and poor-quality joining of sections are minor, which arise due to the low passability of the well, inaccurate determination of the depth of the well, geological conditions, etc. Measures to prevent complications, damages and accidents during well casing, in particular, work on forming the necessary wellbore profile, maintaining the design parameters of drilling fluid, and compliance with the requirements of enterprise standards during preparation works, lowering, cementing and final casing works have been worked out.


2016 ◽  
Vol 20 (2) ◽  
pp. 135-142
Author(s):  
Petro Daniłowicz Stadnyk ◽  
Igor Grigorowicz Dobrotvor ◽  
Katarzyna Szwedziak

AbstractThe paper presents mathematical modelling of determining the power output over the rolling materials in the gap rotating rollers taking into account the rheological parameters of the final product. Determination of these parameters will reduce energy consumption, increase efficiency and reduce loss of material during production. This solution, suggested in the article, allows determination of the overall quality of the rolled product layer. Analysis of experimental results revealed that the main features of the machine provide the necessary stable shape products and provide good rheological parameters of these products. Rheological testing indicators allow for a rational approach to a decision to operate a rolling process. At the same time they improve quality control methods and will have an impact on the design parameters of rollers and modes of chambers. The proposed method not only allows obtaining a predetermined pressure, but also allows defining the optimal shape of the gap, wherein the pressure gradient is constant.


Molecules ◽  
2019 ◽  
Vol 24 (14) ◽  
pp. 2561 ◽  
Author(s):  
Juyuan Luo ◽  
Gongsen Chen ◽  
Donghan Liu ◽  
Yan Wang ◽  
Qi Qi ◽  
...  

Houpo Wenzhong Decoction (HWD) as a classical prescription has been widely used for hundreds of years. However, the quality of HWDs is difficult to control because of its herb materials from different regions. It is a new idea to use HPLC fingerprints, LTQ-ESI-Orbitrap-MS, and network pharmacology in combination to screen common components (CCs) as potential quality control indicators. In this paper, the fingerprints of HWDs were established, which were used to determine HWDs compounded from different sources of traditional Chinese medicines (TCMs). Through the similarity analysis, 45 CCs were selected. UHPLC-LTQ-ESI-Orbitrap-MS was used to carry out the chemical composition analysis of HWD. Seventy-three chemical constituents were distinguished, and 30 CCs were identified. Through network pharmacology, networks of candidate CCs, diseases, and candidate targets were constructed. Finally, four CCs were screened as potential active ingredient markers of HWD, and a method for content determination of these four components was established. A rapid, reasonable, and effective method for quality evaluation and control of HWDs was established. It provides a reference for the further development and research of HWDs and a new way of thinking for the research of other Chinese medicine prescriptions.


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