scholarly journals On adequacy of parameters of strip cross-section profile. Part 2. Local thickenings and thinnings

2021 ◽  
Vol 64 (3) ◽  
pp. 171-177
Author(s):  
S. M. Bel’skii ◽  
I. I. Shopin ◽  
A. N. Shkarin

At present, the cross-section profile of the rolled strip is characterized by geometrical parameters such as wedge, convex, difference of thickness, displacement of convex, and edge wedge. Some of these parameters are redundant. Techniques for calculating the values of these parameters are known and generally accepted. However, there are features of the cross-section profile of rolled strips, such as local thickenings/thinnings, the methods of calculating values of which are not common: practically every scientific school of rolling scientists or specialists of rolling production use their own techniques, which often produce different results for the same cross-section profiles. The problem of identifying and calculating the local thickenings/ thinnings parameters of the rolled strips cross-section profile is to define a so-called “zero level”, the excess/understatement of which is a sign of local thickenings/thinnings. The paper continues to analyze the accuracy and adequacy of the calculation of the cross-section profile parameters of rolled strips for local thickenings/thinnings. A new method based on statistical methods is proposed. The target function that the thickness distribution across the width of the rolled strip must correspond to is a symmetrical quadratic parabola. However, the actual distribution is always different from the target one for a number of reasons, such as ring wear of the work rolls. In the first step, in the proposed technique, the Walter-Shuhart procedure (control cards) eliminates as emissions of strip thickness values that are dramatically different from the target distribution. But since without excluding the nonlinear (parabolic) component of the measured cross-section profile this procedure cannot be applied, it applies to the first derivative of the cross- section profile thickness distribution function. To determine the “zero level,” after calculating the upper and lower limits of the allowed values of the first derivative, all thicknesses associated with these emissions were eliminated. The result of the repetitive process is a “zero level” according to which the local thickening/thinning parameters are calculated.

1976 ◽  
Vol 31 (9-10) ◽  
pp. 612-621 ◽  
Author(s):  
W Müller-Klieser ◽  
W Kreutz

Abstract Mitochondria were isolated using sorbitol and high buffer concentration in the medium. X-ray diffraction patterns arising from the mitochondrial cristae-membrane were recorded in the fully dried state and in two different states in humidity. The Q-function evaluation of these X-ray dif­fraction diagrams resulted in electron density cross-section profiles, which consist of two main peaks of opposite sign and one, respectively two, smaller peaks. The total thickness of the membrane amounts to 120 Å in the dry and 140 Å to 160 Å in the wet state.An interpretation of the cross-section profile is tentatively proposed.


Water History ◽  
2021 ◽  
Author(s):  
Maria C. Monteleone ◽  
Martin Crapper ◽  
Davide Motta

AbstractThe term lacus generally identified the public fountains in the main streets of ancient Roman towns, providing for the population daily water demand. The simplest lacus consisted of a stone basin and a spout stone, concealing one or two supply pipes. 35 street fountains of this type have been surveyed in Pompeii, to gather information on their supply and its variation in time. A new method was devised for calculating the discharge through the overflow channel of each lacus, and this value was taken as an estimate of the water supplied to each fountain. The overflow channel internal cross-section width was measured at four elevations, and the cross-section profile was reconstructed based on these data. Three water levels of 1 cm, half of the cross-section height and entire cross section height, were considered at each channel’s inlet, obtaining a corresponding channel discharge. The values obtained, ranging from 0.03 to 2.9 l/s, were checked against the trajectory of the fountain water jet, making sure that it remained within the basin length. For 28 fountains the average discharge was found to be 0.08 l/s when the water was at the lowest level, 0.43 l/s for the intermediate level and 1.18 l/s for a full inlet. The average time of residence of the water, in the lacus draw basin, was estimated between 11 min and 3 h. An estimate of the demand of all the town lacus was compared with the capacity of the aqueduct channel entering at Porta Vesuvio: the town lacus could have been supplied contemporaneously at the minimum and intermediate discharges.


Author(s):  
I.R. Antypas ◽  
◽  
T.P. Savostina

The use of advanced methods and technologies of threshing and separation allows you to predict and minimize losses. The results of reliability optimization of the cross-section profile of the transporting device and its influence on threshing and separation have not yet been studied. To solve this problem, the article modeled a mathematical numerical model that allows you to describe the function of the cut profile line in a General way. The mathematical model is solved using experimental data.


2021 ◽  
Vol 64 (1) ◽  
pp. 7-13
Author(s):  
S. M. Bel’skii ◽  
I. I. Shopin ◽  
A. N. Shkarin

Increasing the level of automation of metallurgical units and the development of industrial information systems increases the number of p ters of production and technological processes available for analysis. The consequence is an increase in the complexity and duration of preliminary data preparation for subsequent mathematical and statistical analysis. It is therefore important to develop new and improve existing techniques for the automated process of primary data production. When developing methods of primary data preparation, it should be taken into account that accuracy and adequacy of results of subsequent mathematical analysis are determined by accuracy and adequacy of used initial data. The cross-sectional profile parameters of hot-rolled strips, such as wedge, convexity, thickness variation, displacement, wedge in near-rim zones, local thickenings and thinning of the strip are calculated parameters, i.e. secondary to actual strip thickness measurements over the length and width of hot-rolled strips. As technology is improved in cold rolling shops, the number of grade groups is increasing, for which technological modes of units and processing routes are selected. They are based on actual values of parameters of cross-section profile in order to further reduce the probability of formation of inappropriate products and increased metal consumption. The presented article provides an overview of conventional calculation methods for parameters of cross-section profile of hot-rolled strip and gives an assessment of accuracy and adequacy of application of the parameters averaged along strip length to the whole strip.


2020 ◽  
pp. 13-21
Author(s):  
M. M. Sirenko ◽  
B. M. Gorkunov ◽  
S. G. Lvov ◽  
V. V. Lysenko

The paper is about the development of an automated unit with optimum energy and mass-dimensional parameters for high-quality magnetization of magnets of electromagnetic drives, while preser­ving the integrity of their windings. The authors develop an approach for calculating amplitude and width of magnetization pulse. The authors than estimate the rise time of leading edge of the pulse, with respect to conditions of complete magnetization of the electromagnetic drive’s magnetic conductor and preservation of its excitation winding integrity. For the formation of the magnetization pulse with given para­me­ters, the authors propose an electronic device, which feedbacks bitween the drive winding and the pulse current source, which provides power to the inductor winding. The authors propose a method of the inductor magnetic system synthesis by criteria of: given magnetic field strength in inductor’s operating volume; power supply unit minimal dimensions and it power consumption while magnetizing. The final result is obtaining cross-section profile of the inductor electrical coil with certain dimensions and number of winding’s turns of a wire of certain diameter. In order to optimize the mass, size, magnetic and energy para­meters of the inductor, the authors solve a problem of synthesizing its magnetic system in way of calculating the parameters of the magnetic field for operating volume of the inductor. It is determined by the characteristic overall dimensions of the NZTB type electromagnetic drives (brakes, 0.2 m in diameter), which were subject to magnetization in a field with strength of at least 400 A/m. The result is the determination of geometrical parameters and the cross-section profile of the inductor electrical coil. This profile ensures the uniformity of the magnetic field when magnetizing the electromagnetic drive of given overall dimensions. On the basis of all these results, the authors develop the functional scheme of the automated unit and propose a structure of a pa­nel for monitoring and management of devices and units involved.


2018 ◽  
Vol 9 (1) ◽  
pp. 56-65 ◽  
Author(s):  
M. A. Bezuglyi ◽  
N. V. Bezuglaya ◽  
S. Kostuk

The correct accounting of laser emitter parameters for improvement of diagnostic authenticity of methods of optical biomedical diagnostic is important problem for applied biophotonic tasks. The purpose of the current research is estimation of influence of energy distribution profile in transversal section of laser beam on light scattering by human skin layers at photometry by ellipsoidal reflectors.Biomedical photometer with ellipsoidal reflectors for investigation of biological tissue specimens in transmitted and reflected light uses laser probing radiation with infinitely thin, Gauss-type and uniform cross-section profile. Distribution of beams with denoted profiles, which consist of 20 million photons with wavelength 632.8 nm, was modeled by using of Monte-Carlo simulation in human skin layers (corneous layer, epidermis, derma and adipose tissue) of various anatomic thickness and with ellipsoidal reflectors with focal parameter equal to 16.875 mm and eccentricity of 0.66.The modeling results represent that illuminance distribution in zones of photometric imaging is significantly influenced by the laser beam cross-section profile for various thickness of corneous layer and epidermis in transmitted and reflected light, and also derma in reflected light. Illuminance distribution for adipose tissue in reflected and transmitted light, and also derma in transmitted light, practically do not depend of laser beam profile for anatomic thicknesses, which are appropriate for human skin on various sections of body.There are represented results of modified Monte-Carlo simulation method for biomedical photometer with ellipsoidal reflectors during biometry of human skin layers. For highly scattered corneous layer and epidermis the illumination of middle and external rings of photometric images changes depending from the laser beam profile for more than 50 % in transmitted and 30 % in reflected light. For weakly scattering skin layers (derma and adipose layer) the influence of profile can be observed only for derma in reflected layer and is equal not more than 15 %. 


2020 ◽  
Vol 8 (6) ◽  
pp. 4973-4977

The building norms and standards of Uzbekistan on the reinforced concrete structures do not regulate the design of hollow-core slabs of formwork-free shaping, reinforced with prestressed wire reinforcement. The manufacturing technology of such slabs allows creating a wide range of products that increase the possibility of their use in various structural systems in residential, civil and industrial buildings, but in non-seismic areas only. The aim of this work is to develop a constructive solution for the cross section of a prestressed hollow-core floor slab of bench formwork-free shaping, reinforced with high-strength wire reinforcement, in order to create a wide range of products intended for construction in seismic areas. To achieve the goal, the problem of determining the optimal combination of height and configuration parameters of the cross section of such a slab is solved, meeting the normalized operational requirements and limitations of earthquake-resistant building standards. The main variable parameters are the height and the void degree of the section, characterized by the size and shape of voids. In calculating the cross-section of a hollow-core slab when substantiating the theoretical basis for the calculation, the cross section is reduced to the equivalent I-section. As a result of research, a constructive solution was developed for the slab cross section of the maximum parameter values (the span, operational load) set by the customer. The parameters of the slab cross-section are: the height 190 mm, the hollowness 38%, the height of the upper thickened flange (compared with the height of the lower flange) of the given section is 0.27h, the height of the lower flange is 0.17h, the reduced (total) thickness of all ribs “b” is 0.32 of the width of the upper flange. The voids in the section along the height of the slab are arranged asymmetrically. A patent for a utility model has been received for the proposed constructive solution of the slab cross section.


2017 ◽  
Vol 163 ◽  
pp. 00067
Author(s):  
Dieter Ackermann ◽  
Lorenzo Corradi

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