scholarly journals Geometric Parameters of Cutting Tools that Can be Used for Forming Sided Surfaces with Variable Profile

2017 ◽  
Vol 62 (1) ◽  
pp. 33-40
Author(s):  
M. Razumov ◽  
A. Grechukhin ◽  
A. Maslennikov
Keyword(s):  
Cutting Tools ◽  
Planetary Gear ◽  
Geometric Parameters ◽  
Planetary Motion ◽  
Mathematical Formula ◽  
Polyhedral Surfaces ◽  
Clearance Angle ◽  
Minimum Value ◽  
Polygonal Surface ◽  
The Impact

Abstract This article describes machining technology of polyhedral surfaces with varying profile, which is provided by planetary motion of multiblade block tools. The features of the technology and urgency of the problem is indicated. The purpose of the study is to determine the minimum value of the clearance angle of the tool. Also, the study is carried out about changing the value of the front and rear corners during the formation of polygonal surface using a planetary gear. The scheme of calculating the impact of various factors on the value of the minimum clearance angle of the tool and kinematic front and rear corners of the instrument is provided. The mathematical formula for calculating the minimum clearance angle of the tool is given. Also, given the formula for determining the front and rear corners of the tool during driving. This study can be used in the calculation of the design operations forming multifaceted external surfaces with a variable profile by using the planetary gear.

Influence of the backlash generated by tooth accumulated wear on dynamic behavior of compound planetary gear set

2016 ◽  
Vol 231 (11) ◽  
pp. 2025-2041 ◽  
Author(s):  
Shijing Wu ◽  
Haibo Zhang ◽  
Xiaosun Wang ◽  
Zeming Peng ◽  
Kangkang Yang ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Dynamic Model ◽  
Dynamic Behavior ◽  
Planetary Gear ◽  
Tooth Wear ◽  
Transmission Error ◽  
Gear Transmission ◽  
Tooth Surface ◽  
Contact Ratio ◽  
The Impact

Backlash is a key internal excitation on the dynamic response of planetary gear transmission. After the gear transmission running for a long time under load torque, due to tooth wear accumulation, the backlash between the tooth surface of two mating gears increases, which results in a larger and irregular backlash. However, the increasing backlash generated by tooth accumulated wear is generally neglected in lots of dynamics analysis for epicyclic gear trains. In order to investigate the impact of backlash generated by tooth accumulated wear on dynamic behavior of compound planetary gear set, in this work, first a static tooth surface wear prediction model is incorporated with a dynamic iteration methodology to get the increasing backlash generated by tooth accumulated wear for one pair of mating teeth under the condition that contact ratio equals to one. Then in order to introduce the tooth accumulated wear into dynamic model of compound planetary gear set, the backlash excitation generated by tooth accumulated wear for each meshing pair in compound planetary gear set is given under the condition that contact ratio equals to one and does not equal to one. Last, in order to investigate the impact of the increasing backlash generated by tooth accumulated wear on dynamic response of compound planetary gear set, a nonlinear lumped-parameter dynamic model of compound planetary gear set is employed to describe the dynamic relationships of gear transmission under the internal excitations generated by worn profile, meshing stiffness, transmission error, and backlash. The results indicate that the introduction of the increasing backlash generated by tooth accumulated wear makes a significant influence on the bifurcation and chaotic characteristics, dynamic response in time domain, and load sharing behavior of compound planetary gear set.

Dynamics of the Gear Train Set in Wind Turbine

2011 ◽  
Vol 697-698 ◽  
pp. 701-705
Author(s):  
D.D. Ji ◽  
Y.M. Song ◽  
J. Zhang
Keyword(s):  
Wind Turbine ◽  
Dynamic Model ◽  
Harmonic Balance Method ◽  
Planetary Gear ◽  
Gear Train ◽  
Dynamic Responses ◽  
Multi Stage ◽  
Lumped Parameter ◽  
Cartesian Coordinate ◽  
The Impact

A lumped-parameter dynamic model for gear train set in wind turbine is proposed to investigate the dynamics of the speed-increasing gear box. The proposed model is developed in a universal Cartesian coordinate, which includes transversal and torsional deflections of each component, time-varying mesh stiffness, gear profile errors and external excitations. By solving the dynamic model, a modal analysis is performed. The results indicate that the modal properties of the multi-stage gear train in wind turbine are similar to those of a single-stage planetary gear set. A harmonic balance method (HBM) is used to obtain the dynamic responses of the gearing system. The responses give insight into the impact of excitations on the vibrations.

scholarly journals The Role of Thin-Film Vacuum-Plasma Coatings and Their Influence on the Efficiency of Ceramic Cutting Inserts

Coatings ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 287 ◽  
Author(s):  
Marina Volosova ◽  
Sergey Grigoriev ◽  
Alexander Metel ◽  
Alexander Shein
Keyword(s):  
Bending Strength ◽  
Surface Defects ◽  
Cutting Tools ◽  
High Energy ◽  
Radius Of Curvature ◽  
Sic Ceramic ◽  
Operational Tests ◽  
Mechanical Fastening ◽  
Cutting Inserts ◽  
The Impact

The main problem with ceramics used in cutting tools is related to the unpredictable failures caused by the brittle fracturing of ceramic inserts, which is critical for the intermittent milling of cyclic loading. A 125-mm-diameter eight-toothed end mill, with a mechanical fastening of ceramic inserts, was used as a cutting tool for milling hardened steel (102Cr6). For the experiments, square inserts of the Al2O3 + SiC ceramic were used and compared with the samples made of Al2O3 + TiC to confirm the obtained results. The samples were coated with diamond-like coating (DLC), TiZrN, and TiCrAlN coatings, and their bending strength and adhesion were investigated. Investigations into the friction coefficient of the samples and operational tests were also carried out. The effect of smoothing the microroughness and surface defects in comparison with uncoated inserts, which are characteristic of the abrasive processing of ceramics, was investigated and analyzed. The process developed by the authors of the coating process allows for the cleaning and activation of the surface of ceramic inserts using high-energy gas atoms. The impact of these particles on the cutting edge of the insert ensures its sharpening and reduces the radius of curvature of its cutting edges.

Experimental Investigation and Characterization of the Rotating Stall in a High Pressure Centrifugal Compressor: Part II — Influence of Diffuser Geometry on Stage Performance

2002 ◽  
Author(s):  
G. Ferrara ◽  
L. Ferrari ◽  
C. P. Mengoni ◽  
M. De Lucia ◽  
L. Baldassarre
Keyword(s):  
Experimental Tests ◽  
Rotating Stall ◽  
Geometric Parameters ◽  
Flow Coefficient ◽  
Low Flow ◽  
Main Task ◽  
Stage Performance ◽  
The Impact ◽  
Prediction Criteria

Extensive research on centrifugal compressors has been planned. The main task of the research is to improve present prediction criteria coming from the literature with particular attention to low flow coefficient impellers (low width to radius ratios) where they are no more valid. Very little data has been published for this kind of stages, especially for the last stage configuration (with discharge volute). Many experimental tests have been planned to investigate different configurations. A simulated stage with a backward channel upstream, a 2D impeller with a vaneless diffuser and a constant cross section volute downstream constitute the basic configuration. Several diffuser types with different widths, pinch shapes and diffusion ratios were tested. The effect of geometric parameters on stage stability has been discussed inside part I of the present work; the purpose of this part of the work is to illustrate the effect of the same geometric parameters on stage performance and to quantify the impact of stability improvements on stage losses.

scholarly journals THE IMPACT OF THE RESULTS OF PRODUCTION TESTS OF CARBIDE CUTTING TOOLS HARDENED BY A MAGNETIC-PULSE TREATMENT ON INCREASING THE EFFICIENCY OF THE TECHNOLOGICAL CUTTING PROCESS

2018 ◽  
Vol 0 (4 (6)) ◽  
pp. 84-92
Author(s):  
Максим Валерійович Шаповалов ◽  
Віктор Дмитрович Ковальов ◽  
Яна Василівна Васильченко
Keyword(s):  
Cutting Tools ◽  
Cutting Process ◽  
Magnetic Pulse ◽  
Pulse Treatment ◽  
The Impact

Study on the Lateral Deformation of the Flexible Berthing Pile of High-Pile Wharf under Ship Impact Load

2015 ◽  
Vol 744-746 ◽  
pp. 1184-1187
Author(s):  
Qiu Zhai ◽  
Wen Xiang ◽  
Yu Li
Keyword(s):  
Iterative Method ◽  
Analytical Method ◽  
Impact Load ◽  
Correlation Coefficients ◽  
Structure Design ◽  
Horizontal Force ◽  
Lateral Deformation ◽  
Mathematical Formula ◽  
The Impact

Flexible berthing pile-high pile wharf is a system which is composed of flexible berthing pile, rubber fender and pile platform. The system was divided into two forms based on the pile platform sustained the impact load or not. The method to analysis the lateral deformation of the pile was relatively mature when the platform was subjected to the impact load. Instead, when the pile platform is subjected to the impact load, the analytical method is unsatisfactory because of the complexity about the lateral deformation of the system. This paper takes the second condition as the research object, and study the lateral deformation of the pile, rubber fender and the pile platform. The mathematical formula is built on the horizontal force balancing condition and displacement coordination at the top of pile, the method to evaluate the correlation coefficients of the formulas is suggested, and the steps that solve the formulas by iterative method are described. The theory is clear, and the result can offer a reference for structure design and code revision.

scholarly journals The impact of haulroad geometric parameters on open pit mine strip ratio

2019 ◽  
Vol 72 (1 suppl 1) ◽  
pp. 25-31
Author(s):  
Douglas Alexandre Gonçalves Alegre ◽  
Rodrigo de Lemos Peroni ◽  
Eduardo da Rosa Aquino
Keyword(s):  
Open Pit Mine ◽  
Geometric Parameters ◽  
Open Pit ◽  
The Impact

On the Effective Properties of 3D Metamaterials

2016 ◽  
Author(s):  
Mohamed Abdelhamid ◽  
Aleksander Czekanski
Keyword(s):  
Elastic Modulus ◽  
Effective Properties ◽  
Lattice Structure ◽  
Surface Elasticity ◽  
Geometric Parameters ◽  
Stiffness Tensor ◽  
Loading Direction ◽  
Octet Truss ◽  
The Impact ◽  
Effective Mechanical Properties

A continuum-based model is developed for the octet-truss unit cell in order to describe the effective mechanical properties (elastic modulus) of the lattice structure. This model is to include different geometric parameters that impact the structural effects; these parameters are: lattice angle, loading direction, thickness to diameter ratio, diameter to length ratio, and ellipticity. All these geometric parameters are included in the stiffness matrix, and the impact of each parameter on the stiffness tensor is investigated. Specifically, the effect of the lattice angle on the elastic moduli is discussed, and the loading direction of the highest elastic modulus is investigated for different lattice angles. Furthermore, the Gurtin-Murdoch model of surface elasticity is used to include the size effect in the stiffness tensor, as well as anisotropy of this model is investigated.

Parametric Experimental and Numerical Study of LP Diffuser and Exhaust Hoods

2016 ◽  
Author(s):  
Derek Taylor ◽  
Gurnam Singh ◽  
Phil Hemsley ◽  
Martin Claridge
Keyword(s):  
Numerical Study ◽  
Design Guidelines ◽  
Geometric Parameters ◽  
Design Tools ◽  
Steam Turbines ◽  
Exhaust Hood ◽  
Geometric Configurations ◽  
Last Stage ◽  
Lp Turbine ◽  
The Impact

The design of an effective diffuser for a given last stage blade of an LP turbine is known to be highly dependent on the size and shape of the exhaust hood in which it is located. For retrofit steam turbines in particular, where a new last stage blade and diffuser are fitted into an existing exhaust hood, the shapes and sizes of the exhaust box have been seen to vary significantly from one contract to the next. An experimental parametric study of diffuser lips and exhaust hood configurations has been run on a model test turbine rig at GE Power to investigate the impact of various geometric parameters on the performance of the diffusers. Improved testing and post-processing methodologies means the diffuser performance has been obtained for a greater number of geometric configurations than was previously typically possible. The results of these experiments are compared with numerical calculations and confirm the accuracy of the standard in-house diffuser design tools. Key geometric parameters are identified from the test data and used to generate improved diffuser design guidelines.

Effects of Manufacturing Noise on Microturbine Centrifugal Impeller Performance

2012 ◽  
Author(s):  
A. Javed ◽  
R. Pecnik ◽  
M. Olivero ◽  
J. P. van Buijtenen
Keyword(s):  
Performance Analysis ◽  
Three Dimensional ◽  
Geometric Parameters ◽  
Tip Clearance ◽  
Centrifugal Impeller ◽  
Analysis Tool ◽  
Modeling Tools ◽  
Output Performance ◽  
1D Model ◽  
The Impact

This paper presents a study on a small centrifugal impeller for microturbine application from a manufacturing perspective. The aim is to analyze the impact of geometric deviations on part performance using adequate performance modeling tools and statistical methods. A one-dimensional (1D) performance analysis tool has been developed in-house derived from the meanline and two-zone modeling methods. The 1D model has proved to be a simple and computationally inexpensive tool for having a quick performance analysis of the impeller using basic geometric information extracted from part drawings. For the sensitivity analysis, a total of eight input geometric parameters including radii, tip-clearance and blade angles have been varied individually within specific limits in the 1D tool for classifying their influence on the output performance. Since the 1D model is a simplified version of a much complex three-dimensional (3D) model, a commercial computational fluid dynamics (CFD) tool has been used to provide a comparison with the 1D model and scrutinize the effects of such deviations on the fluid behavior inside the impeller passage at a detailed level. For uncertainty quantification, Monte Carlo simulation has been performed using the 1D model to assess the variability of overall impeller output performance to simultaneous random deviations in the input geometric parameters. The study is useful to evaluate the possibility of designing gas turbine parts for manufacturability and superior production cost-effectiveness.

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