Improving Rotary Cutting

2021 ◽  
Vol 41 (11) ◽  
pp. 1065-1066
Author(s):  
A. V. Shchedrin ◽  
A. A. Bekaev ◽  
N. V. Tomskaya
Keyword(s):  
Rotary Cutting

scholarly journals DETERMINATION OF THE MAIN PARAMETERS OF THE ROTARY MOWER CUTTING APPARATUS

2020 ◽  
pp. 77-85
Author(s):  
Dmitry Kondratyuk ◽  
Vitaliy Komaha
Keyword(s):  
Cutting Speed ◽  
Soil Surface ◽  
Angular Speed ◽  
Working Length ◽  
Mode Of Operation ◽  
Basic Parameters ◽  
Rotary Cutting ◽  
The Difference ◽  
Translational Speed

For mowing grass during harvesting of hay or haylage, support-free mowers with rotary movement of knives are used mainly, the productivity of which is much greater than segment-finger mowers. Free-cutting cutting apparatuses with rotational movement of knives happen with their rotation around the vertical (rotary) and horizontal (rotary) axes. Mowers that are equipped with rotary cutting devices significantly grind grass, so they are used in mower-grinders and lawn mowers. The purpose of the work is to substantiate the methodology for calculating the structural and kinematic parameters of rotary cutting devices, corresponding to the conditions of their use. The main parameters characterizing the operation of rotary cutting devices are: area, mows than in one revolution of the disk; knife working length; overlapping knives of adjacent rotors; cutting speed. In determining the basic parameters of the rotary cutting apparatus of the mower, the following assumptions were made. It was believed that the angular speed of the rotor and the translational speed of the mower are unchanged, and the movement of the unit is straightforward. In addition, the cutting apparatus performs mowing in a plane parallel to the soil surface, that is, in a plane perpendicular to most plant stems. It is shown that the absolute speed of any point of the knife varies from the maximum value equal to the sum of the peripheral speed of this point and the aggregation speed of the mower, to the minimum - the difference of the above speeds. It was found that the working length of the cutting edge of the knife is directly proportional to the speed of aggregation of the mower and inversely proportional to the angular velocity of the rotor and the number of knives mounted on it. The overlap of the path of the knives of adjacent rotors depends on the radius of the rotor; the number of knives mounted on it and the kinematic mode of operation of the cutting apparatus. Moreover, an increase in the radius of the rotor requires an increase in overlap, and an increase in the kinematic mode and the number of knives leads to a decrease in the overlap between the paths of the knives. The resulting dependence, which allows you to determine the area, mows than in one revolution of the rotor.

scholarly journals Mathematical Model of Rotary Machined Helical Surfaces

2021 ◽  
Vol 346 ◽  
pp. 01038
Author(s):  
Mikhail Popov
Keyword(s):  
Mathematical Model ◽  
Temperature Decrease ◽  
Mathematical Foundation ◽  
Rotary Tool ◽  
High Durability ◽  
High Temperature Alloys ◽  
Cutting Zone ◽  
Rotary Cutting ◽  
Mathematical Calculation ◽  
Laminated Materials

The rotary cutting method of materials has a number of advantages over the existing traditional cutting methods, e.g. temperature decrease in the cutting zone, also noncumulative blade wear. Due to its high durability, the rotary tool allows processing hardened and difficult-to-machine materials, high-temperature alloys, as well as composite and laminated materials. However, this machining method is usually not applied for machining various shaped surfaces, which is mainly due to the lack of mathematical calculation of the resulting profiles, and the absence of a wide variety of methods for rotary tools installation. The article discusses the mathematical foundation of the resulting profile when processing helical surfaces when processing the flanks of rotary tools.

scholarly journals Cutting Mechanical Study of Pick Cutting Coal Seams with Coal and Rock Interface

2021 ◽  
Author(s):  
Chenxu Luo ◽  
Junbei Qaio
Keyword(s):  
Compressive Strength ◽  
Coal Seam ◽  
Mechanical Model ◽  
Impact Load ◽  
Strength Analysis ◽  
Strength Condition ◽  
Rock Interface ◽  
Coal Rock ◽  
Rotary Cutting ◽  
Mining Coal

Abstract Shearer provide an effect solution for mining coal, and the cutting performance of pick largely accouts for the ability of a shearer and mining performance. We conducted pick cutting coal experiments in different seam forms on the coal and rock cutting teasted. According to the rotary cutting mechanical model of single pick cutting coal seam, combined with the strength condition of coal seam and coal-rock interface, the rotary cutting mechanical model of pick cutting coal seam with coal-rock interface is established. The stress strain and strength condition of the area in and around the interface are analyzed based on the coal-rock interface crushing theory, which provides basis for further research on the cutting mechanical model of single pick crossing the coal-rock interface. According to the analysis on the ampulitude domain, the phenomenon that force increment between the pick cutting rock and uniform coal seam linearly increases with the increase of compressive strength difference between coal seam and coal-rock interface, and the load fluctuation keep a positive correlation with the compressive strength. Analysis on the signals of the pick cutting coal seam with coal and rock interface at different conditions shows that some basic properties of the cutting load changes over times. In addition, the coal seam with coal-rock interface appears larger impact load and other time-domain characteristics.

scholarly journals Tool stability analysis for deep hole drilling

2018 ◽  
Vol 224 ◽  
pp. 01035 ◽  
Author(s):  
Sergey Gorbatyuk ◽  
Valery Kondratenko ◽  
Larisa Sedykh
Keyword(s):  
Stability Analysis ◽  
Cutting Force ◽  
Axial Compression ◽  
Cutting Tools ◽  
Critical Value ◽  
Hole Drilling ◽  
Deep Hole ◽  
Compression Load ◽  
Rotary Cutting ◽  
Rotary Cutting Tools

A large number of parts have deep holes, therefore, rotary cutting tools, which represent relatively long and thin columns are used for holemaking. In this article we analyze the behavior of such tools under the influence of an axial compression load, in our case, the axial cutting force Fp , which differs fundamentally from the compression of short tools. Moreover, experience shows that when the cutting force Fp reaches a certain critical value equal to Fkp , a long straight column becomes unstable.

scholarly journals A Dynamic Analysis of the Rotary Cutting System of King Grass Shredder

2020 ◽  
Vol 145 ◽  
pp. 02080
Author(s):  
Zunxiang Li ◽  
Ou Zhongqing ◽  
Jiao jing ◽  
Huang xiaohong ◽  
Du jihua
Keyword(s):  
Finite Element ◽  
Critical Speed ◽  
Great Influence ◽  
Second Order ◽  
Belt Drive ◽  
Finite Element Models ◽  
Rotating Shaft ◽  
First Order ◽  
Rotary Cutting ◽  
Cutting System

With the rotary cutting system of king grass shredder as the research object, this paper established finite element models for rotating shaft, rotating shaft-belt pulley, rotating shaft-rotary cutting part and rotary cutting system and analyzed the influences of belt pulley and rotary cutting part on the dynamic characteristics of rotary cutting system. The results showed that the belt pulley and rotary cutting part had a great influence on the second order critical speed of rotary cutting system, and the rotary cutting part had a greater influence on the critical speed of first order forward precession than the belt pulley. Meanwhile, the critical speed of rotary cutting system that conformed to facts was calculated. There was a big difference between its first order and second order critical speeds, but the critical speed of first order backward precession was lower. Finally, it was found after analysis that the natural frequency of rotary cutting system was lower than the vibration frequency induced by belt drive, so the shredder can run safely.

Mathematical modeling of a generic multi-profile form milling cutter

2012 ◽  
Vol 227 (5) ◽  
pp. 1036-1046 ◽  
Author(s):  
Mohammed Rajik Khan ◽  
Puneet Tandon
Keyword(s):  
Mathematical Model ◽  
Three Dimensional ◽  
Sculptured Surfaces ◽  
Three Dimensional Model ◽  
Machining Time ◽  
Milling Cutter ◽  
Machined Parts ◽  
Rotary Cutting ◽  
Three Dimensional Models ◽  
The Mathematical Model

In order to machine multiple sculptured surfaces with reduced machining time and high accuracy of the machined parts, shape design of a customised multi-point rotary cutting tool needs to be evolved. In the present work, a novel design of a generic multi-profile form milling cutter is developed for machining various multiple sculptured surfaces. This article describes in detail the mathematical model to design an accurate three-dimensional geometry of a generic multi-profile form milling cutter. Use of non-uniform rational B-spline curve(s) and sweep surfaces enables to control the shape of cutting flutes of the generic multi-profile form milling cutter. The article also discusses the methodology to develop a variety of cutters lying in the same conceptual family of multi-profile form milling cutter. To physically visualise the cutter and to show one of the downstream applications once a three-dimensional model of the cutter is available, one of the multi-profile form milling cutters is fabricated. The proposed methodology offers an intuitive high-quality mathematical model for a generic family of multi-profile form milling cutters, which is different from the traditional three-dimensional models.

Study on the Driven Rotary Cutting of the Hardened Steel

2017 ◽  
Vol 2017.54 (0) ◽  
pp. G025
Author(s):  
Shinnosuke NODA ◽  
Noriyuki TAKASE ◽  
Hideharu KATO ◽  
Naohiko SUZUKI ◽  
Kazuyuki KUBOTA
Keyword(s):  
Hardened Steel ◽  
Rotary Cutting
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