TOOTH LEG EXCESSIVE UNDERCUT ELIMINATION IN HELICAL CYLINDRICAL GEARS WITH PROTUBERANCE OF HOBBING CUTTER BASED ON GRAPHIC RUN-IN

2021 ◽  
Vol 2021 (7) ◽  
pp. 19-27
Author(s):  
Damir Safarov ◽  
Aleksey Kondrashov ◽  
Ayrat Fashudtinov
Keyword(s):  
Boundary Point ◽  
Helical Milling ◽  
Transition Curve ◽  
Design Solution ◽  
Geometrical Parameters ◽  
Milling Cutter ◽  
Cylindrical Gears ◽  
Boundary Points ◽  
Investigation Methods ◽  
Gear Ring

In the paper there are considered procedures for designing a transition curved tooth leg of helical cylindrical gears. A significant parameter of a transition curve is a diameter of boundary points. The boundary point diameter belongs to a bottom point of the involute profile of the teeth side surface of a gear ring. The boundary point position must be lower of the design end point of the involute profile defined by the designer of gearing. A diameter value depends upon a great number of production factors: a profile and wear of a grinding disk, setting up parameters, teeth machining modes of a gear ring, but it is impossible to ensure the specified values of the diameter of boundary points without a correct design solution in the course of the form choice of milling cutter protuberance. The solution on protuberance acceptable parameters of a gear-cutting tool is made by the designer of a cutter during graphic run-in fulfillment. In the paper there are revealed conditions under which arise mistakes in the course of graphic run-in fulfillment within the limits of one teeth pitch of a milling cutter. There are shown recommendations for the fulfillment ensuring the diameter dimension of boundary points of the transition curve specified by the designer of gearing. The data on the design parameter impact of the hob protuberance upon the continuance of cutting edge interaction are shown. There are recommendations given to prevent undercut arising caused by the fulfillment of graphic two-dimensional run-ins of cylindrical helical gears. The work purpose: the elimination of tooth leg excessive undercut in helical cylindrical gears with the protuberance of a worm milling cutter at the expense of the fulfillment of graphic run-in conditions. The investigation methods: the graphical modeling of a run-in process. The investigation results and novelty: there are defined conditions of arising an excessive undercut in the tooth leg of helical cylindrical gears during the fulfillment of graphic run-ins of a tool rack. The conclusions: for mistake prevention in the calculations of the protuberance geometrical parameters of the helical milling cutter the graphic run-in must be carried out not less than on the 1.5 pitch of the milling cutter.

DESIGN OPTIMIZATION OF PROSTHESIS HIP JOINT USING FEM AND DESIGN OF EXPERIMENT APPROACH

2020 ◽  
Vol 32 (06) ◽  
pp. 2050048
Author(s):  
Syed Junaid Ali ◽  
Ashish Goyal ◽  
Manish Dadhich ◽  
Om Shankar Prajapati
Keyword(s):  
Hip Joint ◽  
Design Of Experiment ◽  
Joint Replacement ◽  
Stem Length ◽  
Design Solution ◽  
Geometrical Parameters ◽  
Neck Length ◽  
Hip Joint Replacement ◽  
Ball Diameter ◽  
Base Design

In the present era, hip joint replacement is a well-known medical issue to which the male patients are mostly prone to. There are different designs available for the hip replacement process; however, each design has its benefits as well as its limitations. This study provides the optimum design solution for the hip joint replacement by changing the dimensional parameters of the hip joint. The three geometrical parameters, ball diameter, Neck length and stem length of the hip joint, are selected for the base design. Furthermore, parameters i.e. ball material and stem material are also considered in this study to reduce the weight. The above-mentioned factors have four levels, which help to generate experimental design by using design of experiment methodology. The titanium alloy, Co–Cr-alloy, stainless steel and ultra-high molecule weight polyethylene (UHMWPE) have been selected as working material for modeling of the hip joint. The L[Formula: see text] orthogonal array is simulated in ANSYS FEM solver (Version-14.5). The FEM simulation techniques have been applied, and modeling steps are also developed. Two responses i.e. Von mises stress and body weight are selected to optimize the base design for further study. The signal-to-noise ratio analysis for stress shows that the most significant factor is ball diameter and least significant factor is neck length of the hip joint. For reducing the weight of the entire model, material of stem body is the most significant factor whereas the least significant factor is stem length.

Clustering Boundary Points Detection Algorithm Based on Gradient Binarization

2012 ◽  
Vol 263-266 ◽  
pp. 2358-2363
Author(s):  
Yu Zhen He ◽  
Chun Hong Wang ◽  
Bao Zhi Qiu
Keyword(s):  
Data Processing ◽  
Boundary Point ◽  
Detection Algorithm ◽  
Experimental Results ◽  
Grid Technology ◽  
Gradient Operator ◽  
Boundary Points ◽  
Cluster Boundary ◽  
Novel Algorithm

In order to detect the boundary points of clustering efficiently, we proposed a novel algorithm which combined grid technology and gradient operator. In this algorithm the grid technology is used to enhance the speed of the data processing, and Prewitt gradient operator is applied to calculate gradient in 3×3 grid region from eight directions, the maximum being the central grid gradient. The gradient is used to judge whether the grid is the boundary grid or not, and a point in the boundary grid is a boundary point. Putting the method of image boundary processing into the practice of processing cluster boundary is a fresh idea for the research on cluster boundary. The experimental results indicate that this algorithm can effectively detect boundary of clusters in datasets with noises/outliers and have high running efficiency.

Cutting force model for a small-diameter helical milling cutter

2007 ◽  
Vol 2 (3) ◽  
pp. 272-277
Author(s):  
Xiwen Li ◽  
Mingjin Yang ◽  
Shouyong Xie ◽  
Shuzi Yang
Keyword(s):  
Cutting Force ◽  
Small Diameter ◽  
Helical Milling ◽  
Force Model ◽  
Cutting Force Model ◽  
Milling Cutter

scholarly journals PROCESSING OF HARDENED CYLINDRICAL GEAR WHEELS OF THE CUTTING GEARBOX OF THE COMBINE UKD 200-500

2021 ◽  
pp. 57-70
Author(s):  
Oleksandr Koval'chuk ◽  
Volodymyr Nezhebovs'kyj ◽  
Alexander Permyakov ◽  
Alexander Klochko ◽  
Serhii Riabchenko
Keyword(s):  
Coal Mining ◽  
Lower Boundary ◽  
Cylindrical Gear ◽  
Gear Teeth ◽  
Cylindrical Gears ◽  
Boundary Points ◽  
Gear Grinding ◽  
Gear Wheels ◽  
Technological Methods

The article discusses the latest developments of unique technological methods of gear milling of cylindrical gears for preliminary blade gear processing of hardened cylindrical gears of the cutting reducer of the UKD200-500 coal mining harvester for the final gear grinding of gear teeth with modulus m = 16 mm, with hardness HRC 56 ... 62. The peculiarity of the design of special hob cutters is that a circle passing through the lower boundary points of the involute is used as the palloid of the machine gearing of the tool and part. Pre-cutting the teeth of hardened wheels with carbide milling cutters allows you to remove the main allowance for the final gear grinding.

scholarly journals ADVANCED CENTRAL SPRINGING DEVELOPMENT FOR DIESEL LOCOMOTIVES WITH ADAPTIVE CHARACTERISTICS

2020 ◽  
Vol 2020 (6) ◽  
pp. 31-37
Author(s):  
Evgeniy Slivinskiy ◽  
Valentin Kiselev
Keyword(s):  
Geometrical Parameters ◽  
Diesel Locomotive ◽  
Labor Conditions ◽  
Geometrical Characteristics ◽  
Design Reliability ◽  
Investigation Methods ◽  
Spring Suspension ◽  
Torsion Springs ◽  
Practical Recommendations ◽  
Calculation Procedures

The work purpose - the development of practical recommendations on the spring suspension (developed on the level of invention RU2606409) updating of diesel locomotive 2TE25K body equipped with three-axle bogies and calculation fulfillment for the substantiation of spring suspension basic geometrical parameters. Investigation methods – for realization of the purpose specified there are used modern calculation procedures of adaptive torsion springs that allowed substantiating efficient geometrical characteristics for the central suspension of the diesel locomotive body and there are given practical recommendations on the necessity of such bogies use in practice. Investigation results and novelty – the investigation results are passed to the leadership of the Yelets locomotive depot, it is also recommended to research and industrial heavy engineering bodies both, in our country and abroad with the purpose of its further study and its possible introduction into practice. Conclusions – analyzing the lines offered for locomotive body central suspension updating allows increasing locomotive motion smoothness, improving train crew labor conditions and increasing diesel locomotive design reliability on the whole.

A new stiffness-strength-relationship-based design approach for global buckling prevention of buckling-restrained braces

2020 ◽  
pp. 136943322097478
Author(s):  
Wen-Hao Pan ◽  
Jing-Zhong Tong
Keyword(s):  
Design Procedure ◽  
Design Criterion ◽  
Design Approach ◽  
Design Solution ◽  
Geometrical Parameters ◽  
Element Analysis ◽  
Buckling Restrained Braces ◽  
Global Buckling ◽  
Target Design ◽  
Strength Relationship

This paper proposes a new stiffness-strength-relationship-based design approach that can pinpoint the target design solution for steel buckling-restrained braces (BRB). First, a stiffness–strength requirement interaction curve (the design criterion) with a very simple and easy-to-use form is derived based on a second-order analysis. This interaction curve clearly illustrates the opposing stiffness and strength requirements of the restraining system. Second, based on the geometrical parameters and material properties, a stiffness–strength relationship curve of the BRB restraining system is established. This second relationship curve is expressed by a linear function for a uniform steel BRB. By using the two analytical curves, the point of intersection defines the target design point. A straightforward design procedure for steel BRBs is then developed. A design example of steel BRBs is considered to demonstrate this easy-to-use design procedure for obtaining economical BRB designs. The design is verified and discussed by a rigorous finite element analysis.

scholarly journals Crustal Deformation Across and beyond Central Europe and Its Impact on Land Boundaries

Resources ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 15
Author(s):  
Kamil Maciuk ◽  
Agnieszka Peska-Siwik ◽  
Ahmed El-Mowafy ◽  
Lukasz Borowski ◽  
Michal Apollo
Keyword(s):  
Crustal Deformation ◽  
Boundary Point ◽  
Measurement Errors ◽  
Reference Frames ◽  
Tectonic Plate ◽  
European Continent ◽  
Tectonic Plates ◽  
The Real Estate ◽  
Plate Movement ◽  
Boundary Points

Land is a critical and limited natural resource. The Land Administration System (LAS) has been developed to resolve and adjudicate over any disputes that might arise concerning the rights and boundaries of land. Land registration and cadastre are types of land recording that need to be established. To secure the property rights, we must be sure of accuracy of the boundary points determining the size of the property. However, in addition to typical factors considered when determining the boundary point positions, such as accuracy of geodetic networks and measurement errors, the global and local crustal deformation, resulting, e.g., from the movement of tectonic plates, should be considered. In this work, the focus is on the movement of points inside the European plate due to tectonic movement, without taking into account local events caused by erosion, landslides, etc. The study area is Europe, and particular attention was paid to Poland, which is located in the centre of the European continent and does not have significant anomalous sub-areas, making it an authoritative research object. In this study, we analysed the velocity of point displacements and the boundary deformation, using GPS observations. For this reason, we used both global (IGS) and regional (ETRF) reference frames, to show differences in point velocities for the studied areas. Overall, for the needs of the real estate cadastre in Poland, information about parcel boundary points must be obtained with an accuracy better than 0.30 m. Within 25 years, the border mark may be shifted by 0.13 m due to tectonic plate movement, which is within the required accuracy. Pursuant to the current legal regulations, the measurements of the boundary points can be performed with any method, ensuring the required accuracy (0.30 m). The most commonly used are direct measurements (GNSS and tacheometry) and photogrammetric measurements. It is recommended that periodic verifications and update of the cadastre data in Poland be carried out at least once every 15 years. In the case of such relatively frequent verification and possible modernisation of data, the potential impact of tectonic plate movement on the relative boundary point displacement can be ignored, particularly in the short term. However, for a long time period it has an influence. We suggest “relatively frequent” cadastral boundary verification to be able to ignore such influence.

Study the Surface and Chip Formation of Wood Materials by Milling Method

2021 ◽  
Vol 1047 ◽  
pp. 74-81
Author(s):  
Nguyen Huu Loc ◽  
Tring Quoc Hung
Keyword(s):  
Experimental Study ◽  
Chip Formation ◽  
Chip Thickness ◽  
Response Surfaces ◽  
Geometrical Parameters ◽  
Milling Cutter ◽  
Milled Surface ◽  
Milling Method ◽  
Working Parameters ◽  
Tip Radius

This paper discusses the experimental study and the mechanism of chip formation, sliding and cutting in processing wood milling surface. The main objective is to determine chip thickness upon the coefficient k and tool tip radius ρ. Technically, when analysing we use FCCCD's second-order response surfaces method and analysis of variance (ANOVA) for determining the coefficient k upon the factors of milling cutter diameter D, the feeding per tooth Sz and tool tip radius ρ. According to the obtained experimental results, we determined the value domain of the machine's working factors so that the cutter tool tip can slide or cut the chip on the milled surface of tropical wood materials. From the coefficient k, we can determine the slide length Lsl which gives reason for the abrasion phenomenon of the front or rear sides of the cutter. The results allow us to choose the geometrical parameters ​​for milling cutter, apart from the working parameters for processing the surface of wood materials with the highest quality as possible.

The Effect of Axial Cutting Edge Angle on the Axial Milling Force of Helical Milling

2012 ◽  
Vol 217-219 ◽  
pp. 1723-1728
Author(s):  
Shuo Zhang ◽  
Rui Hang Shi ◽  
Xin Guang Liang ◽  
Yong Xiang Hu ◽  
Zhen Qiang Yao ◽  
...  
Keyword(s):  
Qualitative Analysis ◽  
Process Parameters ◽  
Cutting Edge ◽  
Helical Milling ◽  
Geometrical Parameters ◽  
Milling Force ◽  
Edge Angle ◽  
Machining Quality ◽  
End Mills ◽  
Reasonable Choice

For decreasing axial milling force in helical milling and improving machining quality, researches have been carried out on end mills’ geometrical parameters. And experiments have also been designed to analyze the effect of end mill’s axial cutting edge angle on axial milling force. The results indicate that when other mills’ geometrical and process parameters are constant, the generated mean axial milling force is remarkably decreased, following the axial cutting edge angle’s little increase. In addition, as the pitch of helical milling path increases, larger axial cutting edge angle leads to higher relative decrease ratio. And a qualitative analysis is also put up to point out the reason for the phenomena above, that is, part of the low-speed region of axial cutting edge quits milling. These conclusions could supply valuable references to reasonable choice of combinations of mills’ geometrical and process parameters in helical milling.

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