2016 3rd International Conference on Smart Materials and Nanotechnology in Engineering (SMNE 2016) ISBN: 978-1-60595-338-0

Composite Materials Processing with the Band Saw Blade Crack Before and After the Experiment Analysis (1)

Jingui Gao, Zhaofang Jiang, Jian Zhang Beihua University Jilin City of Jilin Province China

ABSTRACT: This article takes the MJ3210 type woodworking band saw machine as the research object. Under no load, using advanced Beijing pop vibration analyzer and the Vib sys vibration signal acquisition, processing and analysis software for vibration signal acquisition and analysis, through the saw blade transverse vibration displacement, the power spectrum analysis: The saw blade transverse vibration displacement effect on the most significant factor as the spindle speed, followed by the tension of saw blade and belt tension is not significant factors. And draw the best process parameters. Adjust the saw under optimal process parameters. Use 120 mm width is 1.02 mm thick band saw blade type MJ3210 fine woodworking band saw machine, through to the saw blade crack before and after the vibration signal correlation analysis showed that the determination of lateral vibration displacement if between 4.48µm ~ 5.14µm microns, vibration main frequency between 494 Hz ~ 528Hz, and is the saw blade has had at least one more than 3 mm crack defects, need to timely change the band saw blade.

1 GENERAL INSTRUCTIONS Table 1. Main instrument and equipment.

Band saw blade is processing composite band saw Equipment Type Suppliers machine &tooling. Its working state will directly name (and number) affect the machining quality of composite material. Data WS-5942-2-50 Spectrum of Beijing acquisition century science and According to consult literature at home and abroad, instrument technology it is lack of band saw blade under no-load and load Development limited analysis of crack defects. Therefore, this article Static YJ-35 Shanghai automation proposed the preliminary study on the band saw resistance instrumentation limited blade cracks, and sums up its causes and change strain gages shares rule, and then understand deeply the inner relations Company (East China electronic instrument of the factors of crack and fracture mechanism of the factory) saw blade, in order to improve the quality of Proximity HZ-8500 Beijing vibration composite materials processing. sensor measuring instrument factory

2 LABORATORY INSTRUMENTS AND Equipment and sensor installation figure 1 below, EQUIPMENT test system shown in Figure 2-3 below

Transistor DC 2.1 Laboratory instruments MJ3 210 power supply camera Probe Front Instruments used in the experiment are shown in table 1. Computer Data acquisition instrument

Figure 1. Device and sensor installation diagram.

84 3 THE EXPERIMENTAL DATA PROCESSING AND RESULT ANALYSIS

3.1 Bby orthogonal test and analysis of significant

Table 2.Factors of orthogonal test and level.

Factors Level 1 Level 2 Level 3

A-saw round 739 782 831 spindle speed(rpm) B-belt update 1234.9381 1234.9387 1234.9394 tight force(N) C-saw blade 424 422 420 update tight force(N)

According to the fine woodworking band saw Figure 2. Test system. machine for experimental analysis of structure and movement, select the spindle speed, belt tension and the saw blade tension for the experimental factors, to determine impact significant factors of displacement of transverse vibration of band saw blades.3 horizontal x 3 factors L9 (34), orthogonal, bit-level are shown in table 2 below. Test analysis results for: the factors of primary and secondary order mainly → times: A-saw round spindle speed C-saw blade update tight force B-belt update tight force; A-saw round spindle speed C-saw blade update tight force for significantly factors, B- belt update tight force for not significantly factors; optimal program for A-saw round spindle speed 831rpm, and C-saw blade update tight force 122N, and B-belt update tight force 1234.9394N, following experiment in the with saw blade thickness are not variable.

3.2 Saw the wheel spindle speed of displacement of lateral vibration of cracked saw blades and the influence of primary frequency Figure 3.Woodworking band saw machine. Band saw blade tension to 422N, under the premise 2.2 Device and its parameter of the belt tension is 1234.9394N, have 3mm long crack on the intact blades and saws for data 2.2.1 Device and its parameter acquisition, are displacement transverse vibration of This experimental research equipment for the saw blade as shown in Figure 4, master frequency University of North China Institute of forestry curve as shown in Figure 5. MJ3210 woodworking band saw machine All these texts fit in a frame which should not be woodworking machinery laboratory. Its structure changed (Width: Exactly 187 mm (7.36"); Height: consists of upper and lower the saw wheel, band saw Exactly 73 mm (2.87") from top margin; Lock blades, saw blade guides, tightening, dynamical anchor). system, rack, safe cover and other components.As shown in Figure 4.

2.2.2 Machine parameters Equipment: Fine woodworking band saw machine Type: MJ3210 Saw blade diameter: 500mm Saw blade wheel speed: 831rpm.Motor speed: 1400rpm Saw blade parameter: 7550mmx120mmx 1.02mm (length x width x thickness GB/T 21690-2008 Fine woodworking band saw blade dimensions) 85

6 m5 n μ o / Vibration displacement i t t n4 (complete)(μm) a e r m b e3 Vibration displacement i c v a (defects)(μm) l e p2 h s T i d1

0 705 755 805 855 905 Spindle speed/rpm

Figure 4. Intact blades and displacementof the transverse vibration of saw blade tooth defect.

z 520 H / y c 510 n Vibration e u 500 frequency q e (defects)/Hz r f 490 The vibration n o 480 frequency i t (complete)/Hz a r 470 b i V 460 700 750 800 850 900 950 1000 Spindle speed/rpm

Figure 5. Intact blades and the main frequency of vibration of saw blade tooth defects. saw blades generally is less than perfectly preserved By Figure 4,5 visible, saw round spindle speed on main frequency of vibration of the saw blade. with saw blade horizontal vibration displacement, 3.3 Saw blade saw blade tension crack of lateral and main frequency size effect very obviously, saw displacement of vibration and the influence of round spindle speed in 831rpm as saw round speed primary frequency of increased Shi saw blade of horizontal vibration displacement and vibration frequency with of Band saw machine spindle speed of 831rpm, under reduces, saw round spindle speed in 831rpm, as saw the premise of the belt tension is 1234.9394N, 3mm round speed of increased Shi saw blade of horizontal crack saw blades for data collection, are lateral vibration displacement and vibration frequency rate vibration displacement curve band saw blade as with of increases, in saw round spindle speed in shown in Figure 6, master frequency curve as shown 831rpm Shi saw machine reached best work State. in Figure 7. Lateral vibration of a cracked saw blades displacement between 2.27u m~4.98µ m, vibration frequency ratio between 494Hz~514Hz. After cracking main frequency of vibration of the

6 m n 5 o /μ The vibration ti t 4 displacement, a en br m （complete）(μm) i e 3 v ac The vibration l displacement,（The he p 2 T is crack）(μm) d 1 0 418 420 422 424 426 428 430 Blade tension/N

Figure 6.Good saws and produces displacementof lateral vibration of saw blade move crack.

86

530 528 n i z The vibration a /H526 m y frequency on nc524 (complete)(Hz) i e at qu522 Vibration frequency r e (defects)(Hz) ib fr520 V 518

516 418 420 422 424 426 428 430

Blade tension/N

Figure 7. Intact blades and blade vibration frequency of the crack. process of production will differ according to the Figure 6 visible, cracking and intact blade band width of the saw blade, saw blade defects from two saw blade vibration displacement curve movements aspects of vibration displacement and vibration is basically the same, but generally increased, frequency, respectively. resulting in defects cracked saw blades of horizontal 3.5 Equipment running time on defect impact vibration displacement between 3.48um~5.14 µ m. vibration of saw blade By contrast in Figure 7, increase blade tension, blade vibration frequency rate declined and cracks after Pulley spindle speed is 831rpm, the belt tension is the vibration frequency of the vibration frequencies 1234.9387N saw blade tension to 422N, saw blades generally is less than good saw blades. and 30mm wide, crack length 3mm, 20min Their vibration frequencies between 525Hz and collecting data, taking seven observation points draw 528Hz. a curve as shown in table 5, by spectral analysis, curve by the main frequency data as table 6. Comparative analysis on defects of different 3.4 width of saw blade vibration Table 5. Complete saw blade and tooth defects Table 3.Comparison of different displacement comparison of transverse vibration displacement. of lateral. Tree species Poplar Oak wood Saw blade width /mm 110 120 Displacement of lateral vibration of saw 5.4 5.97 Good blade vibration transverse vibration 3.452 5.520 blade tooth defect/μm displacement/µm Displacement of lateral vibration of saw Complete saw blade vibration 3.31 3.37 3.652 5.710 μ blade cracks/µm displacement/ m 110mm wide and 120mm wide cracks in blade crack of saw blades for data acquisition, saw blade crack After table 5 comparative analysis of curve, you 3mm.Transverse vibration of blade displacement can know the when I saw qieyangmu saw blade results as shown in table 3, master frequency data vibration displacement smaller than the curve as shown in table 4. displacement of vibration when sawing oak, describes as the hardness of the cutting of timber Table 4.Comparison of different width of the saw increases, increase the vibration displacement. From blade saw blade vibration frequency. a comparative analysis of primary frequency values, as shown in table 6, saw sawing oak qieyangmu the Saw blade width /mm 110 120 frequency rate than master when frequencies of Good blade vibration 550 570 small, indicating as the hardness of the cutting of frequency/Hz timber increases, clock speed also increases the rate Crack of blade vibration 575 590 and in the process of cutting, when the saw blade frequency/Hz just touch wood when displacement is relatively The table 3 and table 4 shows that there are wide large. blade transverse vibration displacement of defect was obviously higher than that of narrow blade, and the main frequency of the change is wide blade transverse vibration frequency is generally lower than the narrow blade. So in the judgment in the

87 Table 6. Complete saw blade and tooth defects frequency rate than master when frequencies of comparison of main frequency of vibration. small, indicating as the hardness of the cutting of timber increases, clock speed also increases the rate Tree species Poplar wood Oak and in the process of cutting, when the saw blade just touch wood when displacement is relatively Defects of tooth saw blade 570 680 vibration frequency/Hz large. Complete saw blade 550 660 3.6 Devices running time on crack of blade vibration frequency/Hz vibration effects After table 5 comparative analysis of curve, you Use the saw Wheel spindle speed 831rpm, saw blade can know the when I saw qieyangmu saw blade tension 424N, belt tensioning force subject to vibration displacement smaller than the 1234.9394N, 20min collecting data definitions of displacement of vibration when sawing oak, good saws and saw blades for data acquisition and describes as the hardness of the cutting of timber analysis of crack defect by lateral vibration of band increases, increase the vibration displacement. From saw blade displacement as shown in Figure 8. a comparative analysis of primary frequency values, Acquired data are derived from spectral analysis, are as shown in table 6, saw sawing oak qieyangmu the the main frequency as shown in Figure 9.

m 14 e /μ s t 12 er en v m ns e 10 Vibration displacement a ac r l (defects)(μm) t p 8 s Vibration displacement e i 6 ad d (complete)(μm) l n b o 4 w ti a a 2 S br i 0 v 0 20 40 60 80 100 120 140 The elapsed time/min

Figure 8. Intact blades and crack displacements of the transverse vibration of saw blade.

700

600 n i z Vibration frequency a H500 m / (defects)(Hz) n cy o n400 ti ue a q300 The vibration r e frequency ib fr200 V (complete)(Hz) 100 0 0 50 100 150 The elapsed time/min

Figure 9. Fine saw blades and cracks in blade vibration frequency. and the crack length increases from zero to 8 mm, By the curve of figure 8 shows, 80 minutes, teeth number has no obvious change. before changing with running time, the defects of the saw blade vibration displacement, slow after 40 minutes, on 80 minutes to achieve the best state. 4 CONCLUSION From figure 9 shows, the equipment operation began a period of time (40 minutes), band saw blade After more than MJ3210 fine woodworking band transverse vibration main frequency is large, as the saw machine testing and the handling of test data run time increase vibration main frequency, 40 and comparative analysis, reached the following minutes later changes slow. And then instantly conclusions: restore to a steady state, continue to fluctuate in this (1) By orthogonal experiments analysis showed range. Watching tooth at the bottom of the saw blade that MJ3210 woodworking band saw blade vibration off after 100 minutes, found in the drop tooth crack displacement is the most significant factor for the 88 spindle speed, followed by blade tension, belt mechanism and prediction theory research tension for the less obvious factors. (31570556). (2) Experiments, MJ3210 fine woodworking band saw machine saw the best process parameters adjustment of saw blade Wheel spindle speed 6 ABOUT THE AUTHOR 831rpm, saw blade tension 122N, belt tension 1234.9394N, displacement as the minimum Gao Jingui, Ethnic Han, Chinese,Born in December transverse vibration of saw blade. 1963, Professor of forestry engineering in Nanjing (3) In adjustable saw best technology parameter , Forestry Universitypostdoctoral research interests using 16mm width, 0.7mm thick of with saw blade dynamic analysis and design of wood-based panels of MJ3210 type fine woodworking with saw production and woodworking machinery theory. machine saw blade, produced crack of saw blade of To participate in this topic research include: Li vibration displacement will than intact saw blade of Hui professor; Shen De-jun professor; Zhang wei, vibration displacement obviously increases, and associate professor; Hong-gang zhao, an associate vibration frequency rate is will obviously reduces, professor; Dr Jun-hua wu; DrQiHua-Chun; Dr Wu by can bear of maximum saw blade update tight Yan; Huang Jing experimentalist. Liu Ju master; force also will reduces, so, for MJ3210 type fine Zhao Xiu master; GaoKai-bin master; Li Shuang- woodworking with saw machine, judgment saw chang master; Sun Ke master; Zhang Pan master. blade is needs replaced, can from saw blade vibration displacement and vibration main frequency of changes to judgment, dang spindle speed, 7 AUTHOR'S BRIEF INTRODUCTION Belt tension, blade tension is adjusted to the optimal case, determination of transverse vibration Jin-gui Gao The han nationality Jilin province displacement between 4.48um~5.14 µ m, while the dumpling river in December 1963, a professor at the vibration frequency ratio between 494Hz~528Hz, postdoctoral School of materials science and you saw blades have produced at least a 3mm crack, engineering, Nanjing forestry university Mainly the need for timely replacement band saw blades. engaged in the study of theory of composite (4) Defective lateral vibration displacement is materials and processing, composite processing significantly higher than the narrow width of saw machinery dynamic design theory and the research blade saw blades, defective lateral vibration of fault diagnosis frequencies generally above the narrow width of saw blade saw blade, practically judge the situation to be different according to the width of the saw blade saw REFERENCES blade defects, separately from the twofold vibration displacement and vibration frequency judgments. [1] [Zhu Guoxi, Wang Huabin. Study on modern lines. Harbin: Northeast Forestry University Press, September 1989. [2] Gao jingui, Yu Jianguo, Zhu Guoxi, Lai Xiaomin, Dou Jianhua. The elastic dynamics analysis of band saw 5 FUNDING FOR THE SUBJECT PROJECT Tightening system. Journal of Forestry Research.2000. (11): 27-32. This topic by the national natural science fund [3] Gao Jingui. Band sawing machines for mechanical project funding of the People's Republic of China. computer simulation and experimental study of tensioning National natural science foundation of name: Based system [dissertation]. Northeast Forestry University. Library. 2001. on the analysis of time series of woodworking band saw blade crack and loss of tooth formation

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