MECHANICS OF CONTACT IN THE GRINDING OF STEELS

2020 ◽  
Author(s):  
Tat'yana Ivanova ◽  
Vyacheslav Dement'ev ◽  
Oleg Zaharov
Keyword(s):  
Contact Interaction ◽  
Grinding Wheel ◽  
Processing Conditions ◽  
Workpiece Surface ◽  
Actual Contact ◽  
Contact Areas ◽  
Elastic Plastic ◽  
Power And Resistance ◽  
Grinding Tool ◽  
And Control

The article is devoted to the consideration of the issues of contact interaction of a diamond grinding tool with the surface of the part. According to the research results, the actual contact areas were obtained, taking into account the sum of the actual contact areas of the touching bodies, through which the pressing force of the grinding wheel to the treated surface is transmitted, with elastic, plastic and elastic-plastic contacts. The obtained analytical dependences for calculating the geometric parameters of the contact of a diamond face tool with the workpiece surface being machined, allowing to describe, predict and control the power and resistance characteristics of the process on the processing conditions

scholarly journals Prediction of Ground Surfaces by Using the Actual Tool Topography

2019 ◽  
Vol 3 (2) ◽  
pp. 40
Author(s):  
Rolf Hockauf ◽  
Volker Böß ◽  
Thilo Grove ◽  
Berend Denkena
Keyword(s):  
Ground Surface ◽  
Grinding Wheel ◽  
Workpiece Surface ◽  
Precise Knowledge ◽  
Processing Step ◽  
Wheel Topography ◽  
Grinding Wheel Topography ◽  
Grinding Tool ◽  
First Time ◽  
Laser Triangulation Sensor

This paper presents a prediction model for ground surfaces that uses the actual grinding wheel topography to perform a grinding simulation. Precise knowledge of expected machined surfaces plays an important role in process planning. Here, the main criterion is the achievement of the components’ function after manufacturing. Therefore, it is essential to consider the surface roughness to enable a function-orientated workpiece surface. The presented approach uses a real grinding tool topography, which is measured by a 3D laser triangulation sensor in the machine tool. After a data processing step, the measured topography is imported into a material removal simulation. A kinematic simulation of the realistic ground surface enables the data-based confirmation of the envelope profile theory for the first time.

Characterization and Control of Erwinia spp. and Pluralibacter sp. in Tuna Salad Preparations

2019 ◽  
Vol 82 (6) ◽  
pp. 1071-1081
Author(s):  
KRISTIN BJORNSDOTTIR-BUTLER ◽  
SUSAN McCARTHY ◽  
RONALD A. BENNER
Keyword(s):  
Growth Conditions ◽  
Whole Genome ◽  
Processing Conditions ◽  
Optimum Growth ◽  
Significant Growth ◽  
Ph Values ◽  
Histamine Production ◽  
Different Temperatures ◽  
And Control ◽  
Erwinia Persicina

ABSTRACT Histamine-producing Erwinia and Pluralibacter spp. capable of producing toxic histamine levels were isolated from ingredients commonly used in tuna salad preparations. The characterization and control of these histamine-producing bacteria are necessary to prevent illness from tuna salad consumption. We confirmed the identity of two Erwinia spp. and one Pluralibacter sp. previously isolated from tuna salad ingredients through whole genome sequencing and phylogenic analysis and characterized them for growth and histamine production at different temperatures, pH values, and salt concentrations. In addition, we examined the effects of dried vinegar (DV) powder on growth and histamine production of these strains in inoculated tuna salad preparations. Optimum growth temperatures in tryptic soy broth (TSB) for the two Erwinia spp. and one Pluralibacter sp. were 30.1, 31.1, and 33.9°C, respectively, and growth in TSB was observed at 5°C for both genera. Optimum histamine production of Erwinia persicina, Erwinia spp., and Pluralibacter spp. in TSB with histidine occurred from 25 to 30°C, pH 4 to 6, and 0 to 4% NaCl. No significant growth or histamine production was observed in tuna salad preparations stored at 4°C. Growth and histamine production by Erwinia or Pluralibacter spp. was inhibited in tuna salad containing celery and onion and 2% DV, whereas significant growth and histamine production occurred in tuna salad without DV. Understanding optimum growth conditions and histamine production can provide guidance to tuna salad manufacturers in formulating products and adjusting processing conditions that minimize hazards from these histamine-producing bacteria. Addition of 2% DV to tuna salad preparations may prevent histamine production in the event of temperature abuse. HIGHLIGHTS

An Investigation of Local Heat Transfer during Grinding Process—Effects of Porosity of Grinding Wheel

1979 ◽  
Vol 101 (2) ◽  
pp. 97-103 ◽  
Author(s):  
Y. Saito ◽  
N. Nishiwaki ◽  
Y. Ito
Keyword(s):  
Heat Transfer ◽  
Boundary Condition ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Local Heat Transfer ◽  
Local Heat ◽  
Thermal Boundary Condition ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Workpiece Surface

The thermal boundary condition around the workpiece surface is one of important factors to analyze the thermal deformation of a workpiece, which is in close relation to the machining, accuracy of grinding. The heat dissipation from the workpiece surface which is influenced by the flow pattern, may govern this thermal boundary condition. In consequence, it is necessary to clarify the convection heat transfer coefficient and the flow pattern of air and/or grinding fluid around surroundings of a rotating grinding wheel and of a workpiece. Here experiments were carried out in a surface grinding process to measure the flow velocity, wall pressure and local heat transfer by changing the porosity of the grinding wheel. The air blowing out from the grinding wheel which is effected by the porosity may be considered to have large influences on the local heat transfer coefficient, which is found to be neither symmetric nor uniform over the workpiece surface.

Response to William E. Connolly's review of Peripheral Visions: Publics, Power and Performance in Yemen

2010 ◽  
Vol 8 (1) ◽  
pp. 298-300
Author(s):  
Lisa Wedeen
Keyword(s):  
At Risk ◽  
Social Control ◽  
Political Power ◽  
Colonial Rule ◽  
Multiple Points ◽  
Political Experience ◽  
Power And Resistance ◽  
And Performance ◽  
And Control ◽  
Points Of Resistance

William E. Connolly's review of Peripheral Visions is what any author should want, a thoughtful, appreciative account of the book's merits and an invitation to push aspects of the argument further than the book currently does. One point of clarification: I did not mean to suggest that Foucault's work should be read only in terms of its emphasis on coherence and control, or that my own is intended as a blanket critique of his. My understanding of political power and resistance is beholden to Foucault's insofar as he shows how power depends on multiple points of resistance. He thus describes how existing mechanisms of social control get reproduced and yet are also vulnerable to creativity, innovation, and surprise. My point was to challenge Foucault-inspired scholars of colonialism, in particular, who tend to exaggerate the capacities of colonial administrations and to neglect not only outright challenges to colonial rule, but also the ways in which colonial rule could, at times, be irrelevant to inhabitants' political experience. The goal was to distinguish between the stated claims of colonial rulers and colonialism's actual effects. At stake is not simply a reading of Foucault, of course, but a sense of what matters politically—whether scholars emphasize the reproductive power of institutions and ideas or whether they focus on how reproduction places those very ideas and institutions at risk. I want to chart a middle course here, neither exaggerating coherence nor romanticizing resistance.

COMPARISON OF EXPERIMENTALLY MEASURED AND SIMULATED WORKPIECE AND GRINDING WHEEL TOPOGRAPHY USING A NEW DRESSING MODEL

2016 ◽  
Vol 40 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Abdalslam Darafon ◽  
Andrew Warkentin ◽  
Robert Bauer
Keyword(s):  
Surface Finish ◽  
Metal Removal ◽  
Ground Surface ◽  
Cutting Edge ◽  
Edge Density ◽  
Grinding Wheel ◽  
Workpiece Surface ◽  
Wheel Topography ◽  
Grinding Wheel Topography ◽  
Grinding Conditions

This paper presents a new empirical model of the dressing process in grinding which is then incorporated into a 3D metal removal computer simulator to numerically predict the ground surface of a workpiece as well as the dressed surface of the grinding wheel. The proposed model superimposes a ductile cutting dressing model with a grain fracture model to numerically generate the resulting grinding wheel topography and workpiece surface. Grinding experiments were carried out using “fine”, “medium” and “coarse” dressing conditions to validate both the predicted wheel topography as well as the workpiece surface finish. For the grinding conditions used in this research, it was observed that the proposed dressing model is able to accurately predict the resulting workpiece surface finish for all dressing conditions tested. Furthermore, similar trends were observed between the predicted and experimentally-measured grinding wheel topographies when plotting the cutting edge density, average cutting edge width and average cutting edge spacing as a function of depth for all dressing conditions tested.

A Study on the Evaluation Indexes of Wear Process of Electroplated CBN Grinding Wheel

2018 ◽  
Vol 940 ◽  
pp. 72-76
Author(s):  
Fang Quan ◽  
Zhi Tong Chen ◽  
Qian Tong Li ◽  
Huan Ye
Keyword(s):  
Service Life ◽  
Evaluation Index ◽  
Grinding Wheel ◽  
Analytic Hierarchy ◽  
Wear Process ◽  
Evaluation Indexes ◽  
Nickel Based Superalloy ◽  
And Control ◽  
Service Life Cycle ◽  
Cbn Grinding Wheel

The wear process of electroplated CBN grinding wheel is difficult to predict and control because of the lack of unified evaluation index of wear degree. This paper investigates the service life cycle of electroplated CBN grinding wheel in grinding of nickel-based superalloy GH4169. The evolution of topography of grinding wheel, diameter of grinding wheel, grinding force and surface roughness are tracked in the wear process. Using the analytic hierarchy process (AHP), the optimal evaluation index of service life of electroplated CBN grinding wheel is proposed.

An Experimental Investigation of Temperatures in Grinding of Ceramics with a Brazed Diamond Tool

2014 ◽  
Vol 1027 ◽  
pp. 8-11 ◽  
Author(s):  
Xin Xiang ◽  
Jiang Quan Wang ◽  
Jian Yun Shen ◽  
Xi Peng Xu
Keyword(s):  
Diamond Tool ◽  
Measured Temperature ◽  
Moving Heat Source ◽  
Energy Partition ◽  
Matching Method ◽  
Workpiece Surface ◽  
Rectangular Distribution ◽  
Grinding Tool ◽  
Good Relation ◽  
Temperature Responses

An investigation is reported of the relationships of the temperatures and grinding parameter for grinding of ceramics with a brazed diamond grinding tool. During the experiments, the temperature distributions along the workpiece surface were measured using a foil thermocouples and the energy partition to the workpiece estimated using a temperature matching method. The results show that the grinding temperature increased with the increasing of worktable feed rate or tool velocity and depth of grinding. The measured temperature responses were found to be in good relation with the analytical results of a moving heat source with a rectangular distribution at the grinding zone.The energy partition ε is about 23%.

Effect of the Coolant Lubricant Type and Dress Parameters on CBN Grinding Wheels Performance

2009 ◽  
Vol 76-78 ◽  
pp. 163-168 ◽  
Author(s):  
Taghi Tawakoli ◽  
Abdolreza Rasifard ◽  
Alireza Vesali
Keyword(s):  
Grinding Wheel ◽  
Grinding Wheels ◽  
Grinding Forces ◽  
Workpiece Surface ◽  
Vitrified Cbn

The efficiency of using of CBN grinding wheels highly depends on the dressing process as well as on the coolant lubricant used. The Institute of Grinding and Precision Technology (KSF) investigated the performance of vitrified CBN grinding wheels -being dressed using different parameters- while using two different grinding oils and two different water-miscible coolant lubricants. The obtained results show that the performance of the vitrified CBN grinding wheels regarding the quality of the workpiece surface, the grinding forces as well as the wear of the grinding wheel, highly depend on the dressing conditions and the type of the coolant lubricant used. Compared to the water-miscible coolant lubricants, the grinding oils show better results.

Experimental Temperature Studies on Two Dimensional Ultrasonic Vibration Grinding the Nano-ZrO2 Ceramics

2009 ◽  
Vol 416 ◽  
pp. 540-545
Author(s):  
Ping Yan Bian ◽  
Bo Zhao ◽  
Yu Li
Keyword(s):  
Surface Temperature ◽  
Ultrasonic Vibration ◽  
High Surface ◽  
Grinding Wheel ◽  
Grinding Temperature ◽  
Two Dimensional ◽  
Workpiece Surface ◽  
Grinding Parameters ◽  
Thermocouple Method ◽  
The Relationship

In processing of engineering ceramics materials with diamond grinding wheel, grinding heat is one of vital factors influencing workpiece surface quality. Grinding parameters have important influences on workpiece surface temperature distributions. Contrast experiments on grinding temperature of nanoZrO2 under common and two dimensional ultrasonic vibration grinding(TDUVG) were carried out in this paper by manual thermocouple method. The relationship between grinding parameters and grinding temperature was clarified through theoretical analysis and experiment confirmation. The research results show that with the increases of grinding depth, grinding speed, and decrease of working table speed, the workpiece’s surface temperature would heighten accordingly. Furthermore, comparing with high surface layer temperature in common grinding, which often results in grinding burn, TDUVG can reduce grinding temperature effectively.

Experimental Investigations on the Grinding Temperature of the Superhard Grinding Wheel with Ordering Abrasive Pattern

2015 ◽  
Vol 713-715 ◽  
pp. 90-94
Author(s):  
Long Xiang ◽  
Yu Shan Lu ◽  
Jun Wang ◽  
Zhi Zhen Liu ◽  
Shan Zhang ◽  
...  
Keyword(s):  
Temperature Distribution ◽  
Experimental Results ◽  
Experimental Investigations ◽  
Grinding Wheel ◽  
Grinding Temperature ◽  
Workpiece Surface ◽  
Phyllotactic Pattern ◽  
Grinding Parameters ◽  
Matrix Dislocation

In the area of grinding, ordering the abrasive gains is one of the key ways to improve the grinding wheel performance. In this article, the experimental investigations on the grinding temperature were carried out including using the superhard abrasive grinding wheel with phyllotactic, matrix, dislocation and disordered configuration, the temperature distribution of the grinding workpiece surface and the effects of grinding parameters on the temperature of workpiece surface have been obtained. The experimental results showed that the grinding temperature can be reduced efficiently by choicing the grinding wheel with abrasive phyllotactic pattern.

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