CC BY
27
Scientific Research of the Union of Scientists in Bulgaria - Plovdiv,
series B. Natural Sciences and Humanities, Vol. XVII, ISSN 1311-9192, International Conference of Young Scientists, 11 - 13 June 2015, Plovdiv
RESEARCH SEVERITY PARAMETERS DURING PROCESSING MILLING WITH CHANGES IN THE DIRECTION OF MILLS
Bejtulla Krasniqi 1*; Avdi Salihu2; Hakif Zeqiri2; Ahmet Latifi2
1.Ntsh ''Krasniqi '' GJILAN KOSOVO ,2.University of Mitrovica ''ISA
BULETINI'' KOSOVO Address: Livo?i e eperm, Gjilan, KOSOVO [email protected]
Abstract
In the metal processing industry production machines for metal cutting processing of particular importance is the requirement for the quality and accuracy of the work surface in order to increase the time in the car service equipment.To achieve high quality surfaces made, need to know the key factors that influence the severity of the processed surface (micro raised or undulations). Quality surfaces made up of a number of factors, which among themselves are closely connected with the processing conditions, such as processing mode, cooling mode, lubrication, driving stability, working the material microstructure, cutting tool geometry etc.
From the results obtained experimental research severity parameters during milling processing with the change of direction of the milling, the RSt 37-2 stainless steel material according to DIN greatest impact has the of cuting depth (d),cutting feed (f ) and the cutting speed (v). However, this paper is intended to describe the analysis of the results obtained, we conclude that the change of regimes sizes processing parameters vary parameters of severity. There fore, optimization of processing regimes obtained better results roughness parameters Ra, Rt and Rz, but there are other parameters which editability impact on cutting materials and the quality of the processed surface, so it is proposed that in the future to explore the definition of other important factors for evaluating the processing of materials by cutting.
Keywords
Processing with cutting, Milling,Mills, Severity of parameters, Reference length, impact of factors, Quality surfaces
1.Introduction
The purpose of the paper is the severity of experimental research work surface during processing by reaming to change the direction of milling for steel RSt 37-2 according to DIN. All the characteristics of processing(cutting regimes used),factors influencing the severity of this stainless steel surface,the realization of the experiment measurements, mathematical models and analysis of results are given in the relevant chapters,and therefore not presented at the entrance of the paper.
5.0. Conditions of conducting experiment
Research severity during processing parameters with reaming to change the direction of the
milling is examined material of steel RST 37-2 under (DIN s). It is with dimensions (120 x 60 x 20) mm.The sample is processed in universal milling machin UWF Knuth German manufacturing Company which is located in laboratory FATS in Mitrovica, which is shown in Figure 5.1.
Sample processing is used milling with staggered teeth symbolized by the manufacturers standard 885A Din and is using cutting tool holder 40X27X63 TGL2969 / 0316. Measurement of surface severitty parameters is made elaborate computer device for measuring the severity TALYSURF intra of the company TAYLOR HOBSON, shown in Figure 5.5.
Fig. 5.1. Machine with which it is made the Fig. 5.5. Measuring device for measuring the realization of the sample preparation severity of the processed surfaceTALYSURF
(FATS -Mitrovica). -Intra (FATS -Mitrovica)
Table 6.4. Characteristics of cutting regimes and the level of code used
CHARACTERISTICS OF INDEPENDENT VARIABLE SIZES
Nr. sizes level code maximum average minimum
1 0 -1
1. v [m/min] Xi 213.52 169.56 124.34
2. f [mm/min] X2 65 40 24
3. d [mm] X3 0.6 0.4 0.2
Table 6.5. Plan coded matrix of first order with three factors
Nr. Coding levels calculated R>m] InRJ^m] Values
X0 X1 X2 X3 R [p.m]
1 1 124.34 24 0.2 0.2254 -1.4898 0.258
2 1 213.52 24 0.2 0.2451 -1.4060 0.239
3 1 124.34 65 0.2 0.2874 -1.2468 0.301
4 1 213.52 65 0.2 0.2789 -1.2769 0.280
5 1 124.34 24 0.6 0.3500 -1.0498 0.335
6 1 213.52 24 0.6 0.2833 -1.2612 0.311
7 1 124.34 65 0.6 0.3830 -0.9597 0.392
8 1 213.52 65 0.6 0.3338 -1.0972 0.364
9 1 169.56 40 0.4 0.3385 -1.0832 0.316
10 1 169.56 40 0.4 0.3373 -1.0867 0.316
11 1 169.56 40 0.4 0.3112 -1.1673 0.316
12 1 169.56 40 0.4 0.3370 -1.0876 0.316
Mathematicalmodelisgiveninthisform: (4.2)
kv kf kd R= Cn-v v-f -d d
R
Based on the resultsgiven in table6.5,usingscientificmethodsreferredtoexperimentand basedon theperformanceofchapter4,calculatedvalues ofconstantsandcoefficients ofa mathematicalmodel:
Ra=Q.444- v-01365 • f 0 1569 • d 02392 (6.13)
Graphicinterpretationofa mathematicalmodel(6.13)deviationsof
averageroughnesRa[^m] isshown in figure6.9.
theprofilearithmetic
V=213.52 [m/min]
Ra[rtnraj
f [mm/min]
V/
"f [mm/min]
V=169.56[m/min]
d[mm]
■::'«<■ .n l_, i .t i im 'ü. 11.....i: - - .. r.... .il-, ■.... i ....
F., I ::Ö-J. ,P' ': r. LI 1 l-rfj**ci SM! :i) >.
V=124.34[m/min] ■. . V
■
Ra[|imm] -
f[mm/min]
ta^llli hl Ti n j ■ « 4J m a' i Je A itil J1
d[m*ft}-
Fig.6.9.Graphicinterpretationofa mathematicalFig.27. Graphicinterpretationis given, iemodelthe diagram ofprofilegraphsforthe first
experiment
7.0. Analysis of results
On the basis of results obtained experimentally mathematical model for research and graphic interpretation of the parameters of severity during processing by reaming to change the direction of the milling to RSt 37-2 stainless steel material according to DIN standard, is shown the impact of processing regimes for implementation the experiment: cutting speed, cutting feed, and cutting depth. For this research is mathematical statistical methods used by many factors Y= 2k + No, where all factors dependent variable (output), are given in the form of exponential function of the independent variables.Numerical values obtained by mathematical models with reaming the opposite direction and Milling with reaming-way:
Milling with the opposite direction Milling with reaming-way
R =0 444- v"0 1365 • f 0.1569 • d" 2392 R =3 742 • v'0 4605 • f 0.1029 • d<>.3218
a a
R=2 736- v'0.0802 • f 0.2808 • d0.2965 R = 192 74 • v^J358 • f 0.2322 • d0.5534
R =3 016^ v'0.1971 • f 0.2306 • d0 2632 R =27 145^ v'0.5312 • f 0.2282 • d0.4729
z z
By comparing the results obtained on the basis of numerical values for the experiment conducted research severity parameters Ra, Rt and Rz during processing by reaming with the change of direction that milling, drawn conclusions that the experiment conducted by reaming the opposite direction were obtained better results severity parameters comparing the results obtained with reaming-way
8.0. Conclusion
Based on the research results obtained for the parameters of severity during processing with milling to change the direction of milling,the RSt 37-2 stainless steel material according to DIN standard mathematical model analysis of many factors, graphic interpretation is presented impact factors used in the experiment. Realization of the experiment and analytical calculations and the use of literature so far, show the complexity and the conditions in which is the process of cutting and necessity define the surface severity of the milling process, the mathematical model is presented,which has foreseeable changes in physical phenomena and technological effects,processing. From what has been said earlier cutting depth conclude that cutting is the parameter that has the most impact on the severity of surfaces processed in this research.
Reason earned this result is that the first experiment was conducted with milling with opposite direction and milling reaming-way. On the basis of this research is important to emphasize that the biggest impact of the stakeholders in the area of processed severity depends on many factors that are associated with the processing conditions influence the severity parameters appear:the type of processing, cutting regime,geometry of the instrument, tool cooling and lubericant, rigidity of the material processing system settings etc. So it is proposed that in the future to explore the definition of other important factors for evaluating the processing of materials by cutting.
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