scholarly journals Development of an electric measurement system for rapid determination of the friction coefficient

2020 ◽  
Vol 10 (1) ◽  
pp. 39-48
Author(s):  
László Rónai

Development of an electric measurement system for rapid determination of the friction coefficient is discussed in this paper. The electric system is capable to use with a ball cage guide bush unit. Two beam load cells are included into the system and the measured values of the forces are processed by microcontrollers. In the course of measurements, normal- and tangential forces of inner or outer surfaces of different enamelled specimens could be determined. A data acquisition program is developed to record the force values to a personal computer. Linear interpolation method is required to synchronize the values of the load cells, which is necessary to calculate the coefficient of friction.

Author(s):  
V. V. Domasevich ◽  
T. A. Ahmetov ◽  
M. P. Kulgeyko

The main factors of the process of diamond smoothing are considered in the work: the force of the contact interaction of the tool and the part in the deformation zone and the friction on the contact surface of the part and the smoother. The technique of analytical determination of the optimal smoothing force for the finishing-hardening treatment mode is presented. The calculated values were obtained for some characteristic grades of materials of small and medium hardness (≤ 210 HB, indenter radius 3.4 mm) and a number of hardened steels of high hardness (indenter radius 2.0 mm). The force values are also determined using expressions for the deformation component of the friction coefficient. A comparative analysis of the results indicates that the calculation options are adequate for practical purposes. On specific examples of processed materials, graphical dependencies are shown, which reflect the relationship between the coefficient of friction, including its deformation component, and the smoothing force. With an increase in the leveling force, the friction coefficient increases, this is explained by an increase in the depth of penetration of the diamond tip and, consequently, an increase in the deformation component. The depth of penetration of the indenter into the surface to be treated, and therefore the coefficient of friction during ironing, depends on the hardness of the material being processed. With increasing hardness, the penetration depth decreases, which leads to a decrease in the deformation component and in general the coefficient of friction. The friction coefficient is also affected by the radius of the working part of the tool, since the indenter penetration depth also depends on its value. The research results can be used in the development of technology for finishing and hardening diamond smoothing, the development of the process and its introduction into production.


2012 ◽  
Vol 57 (4) ◽  
pp. 921-932 ◽  
Author(s):  
Masoud Soleymani Shishvan ◽  
Javad Sattarvand

Abstract In this paper a new method of modeling variable slope angles has been presented based on the spline interpolation method. Slope angle modeling and defining precedency of the blocks are the vital parts of almost any open pit optimization algorithm. Traditionally heuristic patterns such as 1:5 or 1:9 have been used to generate slope angles. Cone template based models were later employed in developing variable slope angles. They normally use a linear interpolation process for determination of slope angles between the given directions which leads to sharp and non-realistic pits. The other elliptical alternatives suffer from having limitations in defining slope angles in non-geographical directions. The method is capable to consider any number of slope angles in any desired direction as well as creating quite accurate and realistic pit shapes. Three major types of the spline interpolation including cubic, quadratic and cardinal are tested, however, the cubic form is preferred due to more realistic outcomes. Main steps of the method are described through a numerical case study.


Author(s):  
Sergio Filippi ◽  
Esequiel B. Rodrigues ◽  
Muzio M. Gola

The current paper presents a measurement system for the experimental determination of contact hysteresis cycles at temperatures up to 800° C. A test rig was designed to conduct experiments in a wide range of temperatures, with different combinations of normal and tangential load, frequencies and contacting materials. An induction system supplies the heat for measurements of hysteresis cycles at the required temperatures. Measurements show the dependence of the friction coefficient on temperature.


2006 ◽  
Vol 324-325 ◽  
pp. 97-100
Author(s):  
Zhi Qiang Zhang ◽  
Shen Hua Yang ◽  
Shu Qing Kou ◽  
Yong Zhao

Splitting force is the key to the process of fracture splitting connecting rod. In this paper, numerical simulation is made in the process of fracture splitting Jetta car connecting rod by using software MSC.MARC. Through analysis, the curve between J integral and splitting force is established. According to the experiential formula of impact toughness and fracture toughness, critical J integral ( JIC ) can be achieved. After getting JIC , the splitting force can be determined by linear interpolation method and verified by tensile experiment and the error is below 1%. It is proved that this method can also used to analyze other kinds of connecting rods with different materials.


Author(s):  
T. Y. Tan ◽  
W. K. Tice

In studying ion implanted semiconductors and fast neutron irradiated metals, the need for characterizing small dislocation loops having diameters of a few hundred angstrom units usually arises. The weak beam imaging method is a powerful technique for analyzing these loops. Because of the large reduction in stacking fault (SF) fringe spacing at large sg, this method allows for a rapid determination of whether the loop is faulted, and, hence, whether it is a perfect or a Frank partial loop. This method was first used by Bicknell to image small faulted loops in boron implanted silicon. He explained the fringe spacing by kinematical theory, i.e., ≃l/(Sg) in the fault fringe in depth oscillation. The fault image contrast formation mechanism is, however, really more complicated.


2017 ◽  
Vol 45 (2) ◽  
pp. 455-464
Author(s):  
T.T. Xue ◽  
J. Liu ◽  
Y.B. Shen ◽  
G.Q. Liu

2016 ◽  
Vol 1 (20) ◽  
pp. 5-15
Author(s):  
Wojciech Ludwig ◽  
Tadeusz Mączka

The purpose of this paper was presentation of the value of cores electrification during their flow in the modified Wurster apparatus, applied for dry encapsulation of pharmaceutical materials. Previous works of the authors dealt with vulnerability of the particles of different diameter, produced by SYNTAPHARM (Cellets 1000, 700 and 100) on electrification in laboratory conditions. The presented work gives the results of examination on particles electrification in real conditions of their stable circulation in a column. The measurement system, that was applied, allowed determination of electrification potential and electrification current. Those quantities, which are the measures of charge accumulation on cores were determined for several particles (Cellets 1000, 700 and 500) with the different humidity, for different mass of the bed and spouting gas velocities.


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