Improved Design of Driller Based on the Variable Drilling Speed Damping Mechanism

2016 ◽  
Vol 693 ◽  
pp. 146-149
Author(s):  
Dao Lin Wang
Keyword(s):  
Cutting Speed ◽  
Vibration Damping ◽  
Hole Drilling ◽  
Drilling Speed ◽  
Cutting Chatter ◽  
Drill Cutting ◽  
Gear Mechanism ◽  
Improved Design ◽  
Cam Gear

To improve the driller design using the variable drilling speed technology, by attaching to the cam gear mechanism on the driller spindle, adding a mandatory axial vibration to the driller. The vibration of the drilling speed at a certain waveform and within the scope of a certain amplitude of periodic change, in order to achieve the purpose of reducing the radial drill cutting chatter, ensuring processing quality of hole. Based on variable ​​cutting speed technology and the use of vibration damping mechanism, a variable speed apparatus and a cam gear are attached to achieve a vibration damping, to improve hole drilling parts dimension, shape and position of the precision of the accuracy.

scholarly journals Analyzing the Effects of the Kinematic System on the Quality of Holes Drilled in 42CrMo4 + QT Steel

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4046
Author(s):  
Mateusz Bronis ◽  
Edward Miko ◽  
Lukasz Nowakowski
Keyword(s):  
Cutting Speed ◽  
Hole Drilling ◽  
Internal Cooling ◽  
Hole Quality ◽  
The Third ◽  
Kinematic System ◽  
Turning Center ◽  
Dimensional Errors ◽  
The Relationship

This article discusses the relationship between the kinematic system used in drilling and the quality of through-holes. The drilling was done on a CTX Alpha 500 universal turning center using a TiAlN-coated 6.0 mm drill bit with internal cooling, mounted in a driven tool holder. The holes were cut in cylindrical 42CrMo4 + QT steel samples measuring 30 mm in diameter and 30 mm in length. Three types of hole-drilling kinematic systems were considered. The first consisted of a fixed workpiece and a tool performing rotary (primary) and linear motions. In the second system, the workpiece rotated (primary motion) while the tool moved linearly. In the third system, the workpiece and the tool rotated in opposite directions; the tool also moved linearly. The analysis was carried out for four output parameters characterizing the hole quality (i.e., cylindricity, straightness, roundness, and diameter errors). The experiment was designed using the Taguchi approach (orthogonal array). ANOVA multi-factor statistical analysis was used to determine the influence of the input parameters (cutting speed, feed per revolution and type of kinematic system) on the geometrical and dimensional errors of the hole. From the analysis, it is evident that the kinematic system had a significant effect on the hole roundness error.

scholarly journals Material machining for friction knots of moving parts for agricultural machines  

2011 ◽  
Vol 57 (Special Issue) ◽  
pp. S61-S68 ◽  
Author(s):  
J. Žitňanský ◽  
J. Žarnovský ◽  
R. Mikuš ◽  
I. Kováč ◽  
Z. Andrássyová
Keyword(s):  
Cutting Speed ◽  
Cutting Parameters ◽  
Hole Drilling ◽  
Agricultural Machinery ◽  
Sliding Bearings ◽  
Lifting Equipment ◽  
Agricultural Machines ◽  
Machined Surfaces ◽  
Moving Parts

The study deals with the effect of the cutting parameters such as the cutting speed, feed and cooling on the quality of machined surfaces in the process of hole drilling for the sliding bearings used in agricultural technique. This effect has been studied on various metals such as copper, brass, dural and leaded bronze, which are commonly used for their friction knots of the moving parts for agricultural machinery. The results suggest the use in the design of collection parts, scything strips, as well as lifting equipment of agricultural technique, where particular linear and rotary movements of the friction parts are slow, as well as for the design of appropriate drilling procedures.

Assessment of the quality of opening of soil structures technical means developed in Kuban State Agrarian University

2020 ◽  
Author(s):  
B. F. Tarasenko B. F. ◽  
◽  
S. Y. Orlenko S. Y. ◽  
V. V. Kuzmin V. V.
Keyword(s):  
Comparative Analysis ◽  
Field Tests ◽  
Soil Structures ◽  
Improved Design

The article presents a comparative analysis, based on field tests, of the quality of loosening of soil structures of the upper horizon with technical means developed at KubSAU and an improved design of a universal tillage unit.

scholarly journals Dynamic Quality of an Aerostatic Thrust Bearing with a Microgroove and Support Center on Elastic Suspension

Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1492
Author(s):  
Vladimir Kodnyanko ◽  
Stanislav Shatokhin ◽  
Andrey Kurzakov ◽  
Lilia Strok ◽  
Yuri Pikalov ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Negative Impact ◽  
Aerostatic Bearing ◽  
Elastic Suspension ◽  
Variable Parameters ◽  
Aerostatic Bearings ◽  
Improved Design ◽  
Dynamic Quality ◽  
Bearing Layer

The disadvantage of aerostatic bearings is their low dynamic quality. The negative impact on the dynamic characteristics of the bearing is exerted by the volume of air contained in the bearing gap, pockets, and microgrooves located at the outlet of the feeding diaphragms. Reducing the volume of air in the flow path is a resource for increasing the dynamic quality of the aerostatic bearing. This article presents an improved design of an axial aerostatic bearing with simple diaphragms, an annular microgroove, and an elastic suspension of the movable center of the supporting disk. A mathematical model is presented and a methodology for calculating the static characteristics of a bearing and dynamic quality indicators is described. The calculations were carried out using dimensionless quantities, which made it possible to reduce the number of variable parameters. A new method for solving linearized and Laplace-transformed boundary value problems for transformants of air pressure dynamic functions in the bearing layer was applied, which made it possible to obtain a numerical solution of problems sufficient for practice accuracy. The optimization of the criteria for the dynamic quality of the bearing was carried out. It is shown that the use of an elastic suspension of the support center improves its dynamic characteristics by reducing the volume of compressed air in the bearing layer and choosing the optimal volume of the microgroove.

scholarly journals New diagonal micropolarizer arrays designed by an improved model in fourier domain

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jia Hao ◽  
Yan Wang ◽  
Kui Zhou ◽  
Xiaochang Yu ◽  
Yiting Yu
Keyword(s):  
Stokes Parameters ◽  
Fourier Domain ◽  
Extended Model ◽  
Reconstruction Accuracy ◽  
Polarization Imaging ◽  
New Class ◽  
Reconstruction Quality ◽  
Improved Design ◽  
Improved Model

AbstractThe design of micropolarizer array (MPA) patterns in Fourier domain provides an efficient approach to reconstruct and investigate the polarization information. Inspired by Alenin’s works, in this paper, we propose an improved design model to cover both 2 × N MPAs and other original MPAs, by which an entirely new class of MPA patterns is suggested. The performance of the new patterns is evaluated through Fourier domain analysis and numerical simulations compared with the existing MPAs. Particularly, we analyze the reconstruction accuracy of the first three Stokes parameters and degree of linear polarization (DoLP) in detail. The experimental results confirm that the 2 × 2 × 2 MPA provides the highest reconstruction quality of s0, s1, s2 and DoLP in terms of quantitative measures and visual quality, while the 3 × 3 diagonal MPA achieves the state-of-the-art best results in case of single-snapshot systems. The guidance of this extended model and new diagonal MPAs show its massive potential for the division of focal plane (DoFP) polarization imaging applications.

scholarly journals Analysis of machining-induced residual stresses of milled aluminum workpieces, their repeatability, and their resulting distortion

2021 ◽  
Author(s):  
Daniel Weber ◽  
Benjamin Kirsch ◽  
Christopher R. Chighizola ◽  
Christopher R. D’Elia ◽  
Barbara S. Linke ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Cutting Speed ◽  
Past Research ◽  
Hole Drilling ◽  
Statistical Confidence ◽  
Measured Stress ◽  
Main Driver ◽  
Milled Surface ◽  
Force Signal ◽  
Repeatability Standard Deviation

AbstractMachining-induced residual stresses (MIRS) are a main driver for distortion of thin-walled monolithic aluminum workpieces. Before one can develop compensation techniques to minimize distortion, the effect of machining on the MIRS has to be fully understood. This means that not only an investigation of the effect of different process parameters on the MIRS is important. In addition, the repeatability of the MIRS resulting from the same machining condition has to be considered. In past research, statistical confidence of MIRS of machined samples was not focused on. In this paper, the repeatability of the MIRS for different machining modes, consisting of a variation in feed per tooth and cutting speed, is investigated. Multiple hole-drilling measurements within one sample and on different samples, machined with the same parameter set, were part of the investigations. Besides, the effect of two different clamping strategies on the MIRS was investigated. The results show that an overall repeatability for MIRS is given for stable machining (between 16 and 34% repeatability standard deviation of maximum normal MIRS), whereas instable machining, detected by vibrations in the force signal, has worse repeatability (54%) independent of the used clamping strategy. Further experiments, where a 1-mm-thick wafer was removed at the milled surface, show the connection between MIRS and their distortion. A numerical stress analysis reveals that the measured stress data is consistent with machining-induced distortion across and within different machining modes. It was found that more and/or deeper MIRS cause more distortion.

Fuzzy Logic in Hole Drilling of Composites

1994 ◽  
Author(s):  
Aditya Thadani ◽  
Athamaram H. Soni
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Logic Controller ◽  
Thrust Force ◽  
Cutting Speed ◽  
Research Data ◽  
Theoretical Research ◽  
Hole Drilling ◽  
Tool Geometry ◽  
Drilling Process ◽  
And Control

Abstract Experimental and theoretical research data was utilized in building a Fuzzy Logic Controller model applied to simulate the drilling process of composite materials. The objective is to have a better understanding and control of delamination of composites during the drilling process and at the same time to improve the hole finish by controlling fraying and splintering. By controlling the main issues in the drilling process such as feed rate, cutting speed, thrust force, and torque generated in addition to the tool geometry, it is possible to optimize the drilling process avoiding the conventionally encountered problems.

Wet Core Drilling of CFRP with an Electrodeposited Diamond Core Drill - Effects of Cutting Conditions on Chip Evacuation and Core Jamming

2017 ◽  
Vol 749 ◽  
pp. 58-64
Author(s):  
Yuto Kojima ◽  
Ryutaro Tanaka ◽  
Yasuo Yamane ◽  
Katsuhiko Sekiya ◽  
Keiji Yamada
Keyword(s):  
Surface Roughness ◽  
Thrust Force ◽  
Cutting Speed ◽  
Hole Drilling ◽  
Exit Point ◽  
Grain Sizes ◽  
Normal Core ◽  
Tool Shape ◽  
Wet Condition ◽  
On Chip

This study investigated the cutting characteristics of electrodeposited diamond core drill when used to drill a CFRP under wet condition. The effects of different tool shapes, grain sizes and feed rates were examined. A normal core drill, an eccentric with slits core drill (E.S.), and an eccentric with slits and chamfers core drill (E.S.C.) were used. The normal core drill had the shape of a hollow cylinder. The E.S. core drill had the inner cylinder shifted from the center of this tool and slits in the bottom of this tool. The E.S.C. core drill had chamfers on the periphery of this tool. The normal core drill caused severe workpiece core jamming even at 1st hole drilling, and its electro-deposited area was covered entirely by adhered chips. In the case of the E.S. core drill and E.S.C. core drill, the workpiece core did not jam and the thrust force was smaller than that of the normal core drill. The effect of chamfers was little. The E.S.C. core drill with #200 caused smaller surface roughness than that with #100. However, the thrust force was two times larger, and the delamination was observed at the exit point of the hole. In the lower feed rate per revolution the better surface roughness and the lower thrust force were obtained irrespective of the tool shape while the cutting speed showed little effect.

Microtexture Generation Using Controlled Chatter Machining in Ultraprecision Diamond Turning

2015 ◽  
Vol 3 (2) ◽  
Author(s):  
Syed Adnan Ahmed ◽  
Jeong Hoon Ko ◽  
Sathyan Subbiah ◽  
Swee Hock Yeo
Keyword(s):  
Cutting Tool ◽  
Cutting Speed ◽  
Diamond Turning ◽  
Diamond Cutting ◽  
Machined Surface ◽  
Excited Vibration ◽  
Mass And Heat Transfer ◽  
Tool Shank ◽  
Diamond Cutting Tool

This paper describes a new method of microtexture generation in precision machining through self-excited vibrations of a diamond cutting tool. Conventionally, a cutting tool vibration or chatter is detrimental to the quality of the machined surface. In this study, an attempt is made to use the cutting tool's self-excited vibration during a cutting beneficially to generate microtextures. This approach is named as “controlled chatter machining (CCM).” Modal analysis is first performed to study the dynamic behavior of the cutting tool. Turning processes are then conducted by varying the tool holder length as a means to control vibration. The experimental results indicate that the self-excited diamond cutting tool can generate microtextures of various shapes, which depend on the cutting tool shank, cutting speed, feed, and cutting depth. The potential application of this proposed technique is to create microtextures in microchannels and microcavities to be used in mass and heat transfer applications.

Research on Water Cut of Silicon Steel Plate

2012 ◽  
Vol 503-504 ◽  
pp. 367-369
Author(s):  
Geng Wu Liu
Keyword(s):  
Steel Plate ◽  
Water Pressure ◽  
Cutting Speed ◽  
Silicon Steel ◽  
Cutting Test ◽  
Water Cutting ◽  
Water Cut ◽  
Magnetic Conductivity ◽  
Main Material

Silicon steel plate is main material of motor and transformer , and was always used die for its production . Through water cutting test , the cutting speed of beeline and arc and water pressure was adjusted , the water cutting technology was mastered . The quality of production such as dimension , burr height was controlled well . The cut area was not rust because of using dry technology and the magnetic conductivity was not affected using water cutting . It will provides a speediness way for silicon steel plate production .

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