Speed Machining Research Articles

Online tracking of dynamically time-varying inertia using an enhanced SDFT-based estimation methodology

The overall motion performance of mechatronic machines depends heavily on proper knowledge of the machine’s characteristics, among which the inertia. Moreover, the inertia of most multi-body mechanisms, for example, reciprocating slider-crank mechanisms, varies as a function of the machine position, thereby challenging optimal control. Nevertheless, the inertia’s variation is sometimes not known accurately enough or changes over time due to, e.g. a production process or premature wear, forcing an online control/correction of the inertia profile. Therefore, earlier, the author developed a new computational-friendly online method based on a frequency-specific magnitude response to estimate the machine’s position-dependent load side inertia, assuming good knowledge of all other machine properties. Yet, to guarantee accuracy, the maximum machine speed during estimation had to be strongly reduced, resulting in an undesirable longer motion time. Therefore, in this work, the failure mechanism of the earlier proposed estimator is analysed and overcome by intelligently separating estimation and motion signals. As a result, the estimator is no longer limited by the machine’s motion speed but rather by a maximum in the inertia variation per signal excitation period and, thus, time. Moreover, given this limiting variation, a guideline was established to evaluate the new method’s estimation quality. Finally, both in simulation and on a physical machine, by taking advantage of the newly proposed method, the minimal required estimation time is reduced significantly (up to 50% on the machine) without diminishing the estimation accuracy.

Development and optimization of a mechanized jackfruit processing unit for enhanced efficiency and commercial viability

AbstractThe jackfruit is the largest edible fruit but remains underutilized due to challenges such as sticky latex, labor‐intensive peeling/coring, and lack of mechanization. This study developed and evaluated a jackfruit peeling, coring, and cutting machine to enhance processing efficiency. Performance was modeled using response surface methodology (RSM) and artificial neural network (ANN). Three jackfruit sizes (small, medium, and large) and three machine speeds (90, 120, and 150 RPM) were evaluated for peeling time (26.1–50.3 s), peeling efficiency (71.6%–85.3%), coring time (15.5–29.9 s), coring efficiency (74.7%–96.0%), and bulb wastage (6.2%–17.6%). RSM showed high model adequacy (R2 ≥ 0.97) and ANN confirmed prediction reliability (R2 = 0.81–0.99; mean square error = 4.4–44.9). Increasing fruit size significantly increased peeling and coring times but decreased efficiencies. Machine speeds caused minor variations. Optimized conditions of 120 RPM fruit holder speed and 150 RPM corer speed gave maximum desirability (0.869). The machine had a payback period of 2 years and benefit–cost ratio of 2.32 versus 2.66 for manual peeling/coring. The mechanized jackfruit processing will promote enhanced utilization of this nutritious fruit.Practical applicationsThe mechanized jackfruit peeling‐coring‐cutting machine developed in this study has significant practical utility. By enabling efficient and rapid processing of jackfruits, the machine can help tap the underutilized potential of this highly nutritious and functionally beneficial fruit. The optimized machine parameters allow jackfruit processing industries to achieve higher throughput with reduced wastage, thereby boosting productivity and profits. Additionally, the mechanization facilitates value‐addition by enabling jackfruit utilization in various processed products like chips, flour, jam, etc. Further, the machine helps create livelihood opportunities in jackfruit value chains, as it reduces drudgery and enhances process efficiency as compared to manual methods. The simple fabrication and operation also enable adoption by farmer‐producer organizations, self‐help groups, and community‐based jackfruit processing enterprises. Overall, the mechanized solution provides an impetus for sustainable utilization of jackfruit, while also addressing issues like food loss, nutrition security, income support, and women empowerment. The practical insights on machine performance modeling using response surface methodology and artificial neural network approaches further facilitate quality improvements in equipment design.

Регулирование технологических скоростей

Depending on the requirements of the technology and the operator factor, the operating speeds of technological machines can vary in different intervals. It is proposed to distinguish between small and large ranges of technological speed changes relative to the variator control range. If the range of speed changes goes beyond the control range of the variator, then it will be a large range, and otherwise it will be a small range. The working speed of the technological machine can be changed stepwise or continuously. Step-by-step speed control is carried out using a gearbox, and stepless regulation is carried out using a variator. The technological speed in a large range is recommended to be steplessly adjusted using a variator and a gearbox, and in a small range – using a variator and a gearbox. A V-belt variator with a standard V-belt drive is proposed, the main tasks of its development are defined.

Development and Optimization of Cassava (Manihot Esculenta) Peeling Machine

The conventional cassava peeling methods are inefficient, time-consuming, and labor-intensive This study aimed to create an enhanced cassava peeling machine with minimal flesh loss. The machine design includes components like a hopper, shafts, bearings, an electric motor, and a v belt connected to a pulley that drives the brush-equipped shaft. This locally sourced and fabricated machine, designed for 50kg of cassava tubers, was tested at operational speeds of 380, 420, and 460 rpm and retention times of 4, 6, and 8 minutes, optimizing the effects of machine speeds and peeling times on peeling efficiency using I-optimal Response Surface Experimental Design with a mean separation at P<0.05. Results pertaining to tuber properties, such as angle of repose, peel thickness, moisture content, peel penetration force, bulk density, and coefficient of friction, were utilized in the machine's design. The machine achieved maximum peeling efficiency of 74% at a speed of 380m/s when operated for 6 minutes. At this optimal efficiency, the machine reached an optimal throughput capacity of 171.4kg/h, with a 21% flesh loss, a peeling weight proportion of 25.8%, and minimal tuber damage (3.3%). The desirability, which signifies the extent to which these optimal values align with the optimization goal, was 0.83 (83%). In essence, this machine significantly advances cassava peeling mechanization.

Classification of CNC Vibration Speeds by Heralick Features

In the contemporary landscape of industrial manufacturing, the concept of computer numerical control (CNC) has emerged due to the optimization of conventional machinery, distinguished by its remarkable precision and expeditious processing capabilities. These inherent advantages have seamlessly paved the way for the pervasive integration of CNC machines across a myriad of industrial manufacturing sectors. The present study embarks upon a comprehensive inquiry, delving into the intricate analysis of a specialized prototype CNC molding machine, encompassing a meticulous assessment of its structural rigidity, robustness, and propensity for vibrational occurrences. Moreover, an insightful exploration is undertaken to discern the intricate interplay between vibrational signals and intricate machining processes, particularly under diverse conditions such as the presence or absence of the cutting tool, and at varying rotational speeds denoted in revolutions per minute (RPM). The trajectory of this research voyage encompasses an extensive array of empirical experiments meticulously conducted on the prototype CNC machine, with synchronous real-time acquisition of vibrational data. This empirical journey starts by generating two distinct datasets, each meticulously designed to encompass an assemblage of seven distinct rotational speeds, spanning the spectrum from 18000 to 30000 RPM, thereby facilitating enhanced diversity within the dataset. In parallel, a secondary dataset is meticulously derived from the CNC machine operating in the absence of the cutting tool, thereby encapsulating an exhaustive range of 20 discrete RPM values. The extraction of pivotal features aimed at discerning between the vibrational signals arising from distinct conditions (i.e., those emanating from situations involving the presence or absence of the cutting tool) and the associated variance in CNC machine speeds is facilitated through an innovative framework grounded in co-occurrence matrices. The culmination of this methodological framework is the identification of discernible co-occurrence matrices, thereby facilitating the subsequent computation of Heralick features. The classification effort was performed systematically using 10-fold cross-validation analysis, covering a number of different machine learning models. The outcomes emanating from this intricate sequence of systematic methodologies underscore remarkable achievements. Specifically, the classification of vibrational signals corresponding to varying CNC machine speeds, contingent upon the presence or absence of the cutting tool, yields commendable accuracy rates of 94.27% and 94.16%, respectively. Notably, an exemplary accuracy rate of 100% is attained when classifying differing conditions (i.e., situations involving the presence or absence of the cutting tool) across specific RPM settings, prominently at 22000  24000  26000  28000  and 30000 RPM. 

Uji Kinerja Alat Pencacah Rumput (Mini Chopper) Type TMB 01

The high amount of food crop production in East Lampung Regency produces abundant biomass. This biomass can be used as silage for animal feed. A grass chopper is needed to make silage. The aim of the research was to test the performance of the TMB 01 type grass chopper on corn stalks and elephant grass with engine rotation speeds of 800, 1000 and 1200 rpm. This research was carried out in June - November 2023, at the Self-Help Agricultural and Rural Training Center (P4S) Tani's Market Balerejo, East Lampung Regency. This research was carried out with observation parameters measuring chopping time, measuring machine rotation speed, measuring fuel consumption, measuring the diversity of biomass mass that had been chopped. The research results show that rotational speed (rpm) influences work capacity, working time, fuel consumption and chopping diversity. The best rotation speed of the shredding machine is 1200 rpm. Keywords: Biomass, Engine Revolution, Shredding Machine, Work Capacity.

Academician V.N. Boltinsky’s Scientific article Legacy in Agricultural Engineering Education and Science (Commemorating the 120th Anniversary of the Birth)

The article delves into the scientific contributions and advancements of the eminent Russian scientist in agricultural tractor construction, Vasily Nikolaevich Boltinsky. (Research purpose) The paper aims to shape and consolidate historical, scientific, engineering and technical concepts regarding the establishment and development of scientific and pedagogical institutions focused on the study of tractor engine operation and machine-tractor units in unsteady modes. It also seeks to underscore the contributions made by Doctor of Technical Sciences, Professor, and Member of VASKHNIL, V.N. Boltinsky. (Materials and methods) The study employs a chronological approach, utilizing historical, scientific, and informational resources, including publications by prominent scientists and original works by the academician himself. The paper also analyzes and summarizes historical facts detailing the role of V.N. Boltinsky in enhancing the design and efficiency of Soviet tractors and machinery units. (Results and discussions) Throughout his career, from assistant to associate professor to vice-president of VASKHNIL, V.N. Boltinsky dedicated himself to developing and testing new models of both foreign and domestic tractor equipment. His extensive experience and years of research culminated in the publication of the monograph «Operation of a tractor engine under unsteady load», which extensively explores the impact of varying loads on engine performance. V.N. Boltinsky successfully solved problems related to enhancing the operational speed of machine and tractor units, as well as innovating the design of agricultural machinery. (Conclusions) The life and professional endeavors of V.N. Boltinsky serve as a shining example of dedication to science, education, and the professional advancement of engineering and scientific professionals. To honor his legacy, an annual scientific and practical seminar entitled «Academician V.N. Boltinsky Readings» is held in Russia, ensuring his contributions continue to be celebrated and remembered.

Research on dynamic characteristics of cutter breaking frozen soil and optimal drum rotation speed of the new shaft tunneling machine

To improve the efficiency of frozen soil excavation, the new shaft tunneling machine was developed. The new shaft tunneling machine exerts pressure on the frozen soil through the cutter under the joint action of its own gravity, the drum rotational force and the inertia force, and the frozen soil is damaged. By unique way of breaking frozen soil to improve the efficiency of frozen soil excavation, the drum rotation speed is one of the factors affecting the performance of frozen soil excavation. This article applies SolidWorks software to establish the model of cutter breaking frozen soil, takes advantage of Hyper Mesh finite element software coupled with LS-DYNA solver to acquire the regular pattern of change in the force change, frozen soil stress–strain and specific energy of cutter crushing frozen soil, etc., which analyzes the destruction of frozen soil when the drum of the new shaft tunneling machine is rotating at the speed of 25–40 rpm. Combine with field test to investigate the mechanism of cutter breaking frozen soil under the optimal drum rotation speed. The investigation results demonstrate that: when frozen soil's self-bearing capacity is lower than the force of cutter, it breaks up and detaches from the soil body, and frozen soil undergoes tensile, compressive and shear damages. For this research, it is instructive for practical engineering.

Approximation algorithms for job scheduling with block-type conflict graphs

The problem of scheduling jobs on parallel machines (identical, uniform, or unrelated), under incompatibility relation modeled as a block graph, under the makespan optimality criterion, is considered in this paper. No two jobs that are in the relation (equivalently in the same block) may be scheduled on the same machine in this model.The presented model stems from a well-established line of research combining scheduling theory with methods relevant to graph coloring. Recently, cluster graphs and their extensions like block graphs were given additional attention. We complement hardness results provided by other researchers for block graphs by providing approximation algorithms. In particular, we provide a 2-approximation algorithm for P|G=block graph|Cmax and a PTAS for the case when the jobs are unit time in addition. In the case of uniform machines, we analyze two cases. The first one is when the number of blocks is bounded, i.e. Q|G=k − block graph|Cmax. For this case, we provide a PTAS, improving upon results presented by D. Page and R. Solis-Oba. The improvement is two-fold: we allow richer graph structure, and we allow the number of machine speeds to be part of the input. Due to strong NP-hardness of Q|G=2 − clique graph|Cmax, the result establishes the approximation status of Q|G=k − block graph|Cmax. The PTAS might be of independent interest because the problem is tightly related to the NUMERICAL k-DIMENSIONAL MATCHING WITH TARGET SUMS problem. The second case that we analyze is when the number of blocks is arbitrary, but the number of cut-vertices is bounded and jobs are of unit time. In this case, we present an exact algorithm. In addition, we present an FPTAS for graphs with bounded treewidth and a bounded number of unrelated machines.The paper ends with extensive tests of the selected algorithms.

Investigating the thickness of patterned polyethylene layers by changing the line speed and temperature in the embossing machine

Patterned polyethylene films are mandatory products in the rubber tire industry. They are used as protective lining to prevent contamination of the rubber. This pattern geometry (2D and 3D) prevents the rubber from sticking to each other. The film is desired to be homogeneous, precise in thickness, and have sufficient mechanical strength. The speed and the temperature of the pattern-forming machine are among the factors that determine this relationship between the thickness of the film and its mechanical properties for sustainable quality production. In this study, the effect of the speed and the temperature of the pattern machine on the pattern thickness during the creation of the pyramid-shaped pattern applied on a 100 ± 5 µm thick polyethylene film were examined. Four different machine speeds (24, 26, 28, and 30 m/min) and three different temperatures (100, 110, and 120 °C) were studied as variables. The impact of parameters on film thicknesses and tensile properties was assessed. Film thickness varied from ~ 375 to ~ 340 µm at higher machine speed, strength-at-break values decreased from 28 to 22 MPa, and elongation values dropped from 575 to 437% with the increment in speed. On the other hand, at higher temperatures, thickness rose from ~ 360 to ~ 390 µm, and elongation values reduced from 440 to 410%. Within the scope of the experimental studies, it was observed that the film thickness changes and the mechanical properties can be controlled by changing the line speed or process temperature.Graphical abstract

Fuzzy Logic Control of Asynchronous Machine Drives With a Fractional Calculus Technique

—This paper proposes the use of fractional-order fuzzy logic (FOFL) to control the rotational speed of asynchronous machines (AMs) using the pulse width modulation and compares the results with field-oriented command (FOC). The contributions of this paper are to use FOFL instead of proportional-integral (PI) controller to control torque and flux and prove that it can reduce torque ripple and increase durability of control system. This work reveals that this strategy is very suitable to efficiently control systems without knowing their mathematical model, as is the case with FOC. The FOFL is tested with numerical simulations conducted in Matlab software under the different tests, where the obtained results are compared with FOC. The simulation results showed that the FOFL provided a clearly better performance in decreasing the torque, current, and flux ripples, where, compared to the FOC, the ripple reduction ratio was estimated at 44.44%, 51.72%, and 80.95% for torque, current, and flux, respectively. In addition, the FOFL reduces the time responses for changes in the speed, flux, and torque, where, compared to FOC, the FOFL minimized the time response by rates estimated at 4.47%, 94.77%, and 89.44% for each of the speed, flux, and torque, respectively.

Rotary speed control on Continuous Passive Motion (CPM) Therapy Machine Device with PI Control

Continuous Passive Motion (CPM) Machine is a therapeutic device that is used to assist the process of therapy and recovery of a patient after having joint surgeryor injury of the ankle. In this research, a CPM machine will be developed for ankle joint therapy. The rotation speed of the CPM machine will be controlled by a DC motor which is used to drive the ankle joint therapy device.Speed control for DC motor is used on a therapeutic device (CPM machine) to determine the level of the therapeutic process; therefore this device can be adjusted to the needs of the patient who will use the therapeutic device. Speed control of the DC motor that will be carried out in this research is using Proportional Integral (PI) control. With the PI control, the result of output will always be compared with the set point value. The result of this comparison will provide an error value, which later the error value will be processed by PI control.The PI values used in this research are Kp 5 and Ki 15.The test results of the CPM movement speed show that the difference between the set point and the resulting movement is 1 RPM. Where the speed tested on this tool is 3 RPM and 5 RPM. So, the output of this device will be as expected. In brief of this research, a therapeutic device that can be adjusted the rotational speed as expected.

Advancing the Engineering Approach to Improving the Quality Cracking Efficiency of Palm Nut Crackiing Machine

A Palm Nut cracking machine with an improved beater configuration was developed to effectively crack Palm Nuts of various species and sizes. This research aim at improving the quality of the Palm kernel recovered at relatively low cost during Palm kernel oil production. Durable materials were acquired locally to fabricate the machine for ease of usage and maintenance, also to make it affordable for small and large scale processors. Basic features of the machine are; hopper, electric motor (prime mower), cracking chamber, cracking beater and discharge outlet. The design of the cracking drum and beater configuration was based on the impact force required to crack the Palm Nut which is a function of Palm Nut shear strength. A 5 hp electric motor was selected based on the power required to effectively operate the machine. The machine was tested with “Tenera” varieties, three nut sizes (14.5, 22.15 and 29.43mm) and five speeds (970, 1200, 1450, 1750 and 2430rpm). Result shows that the change in machine speed significantly (P<0.05) affects all the machine performance irrespective of the Palm Nut size and variety, which agrees with the report of several other researchers. The obtained optimum machine performance values are 14,874 nuts/h, 89.5%, 98% for the machine capacity, quality performance efficiency and cracking efficiency for Tenera variety. The best crop and machine parameter for the optimum performance of the Palm Nutcracker are 29.43 mm and 970 rpm, nut size and machine speed. It was concluded that the overall performance of this developed Palm Nut cracking beater was effective because it fell within the range of 80 to 98% efficiency.

Research on the Characteristics of Stirring Flow Field of Flotation Separator Based on PIV Technology

In order to explore the distribution characteristics and characteristics of the internal flow field of the flotation machine, and to understand the variation law of the flow field parameters in the process of the internal flow field of the flotation machine, particle image velocimetry was used to measure the flow field of the flotation machine, and four groups of sections were designed, each group of sections had four different revolutions, and there were 16 experimental groups in total. The results show that the vertical plane of the flow field of flotation machine can be roughly divided into four areas. The flow field level of the flotation machine can also be divided into three areas. The effect of rotating speed on the average circulating speed of flotation machine was studied. This paper analyzes the statistical law of vorticity distribution in the internal flow field of flotation machine and the relationship between average speed and rotating speed, and establishes the probability model and influence analysis model related to it.

Block processing time-based programming for high-speed, high-precision 5-axis machining

For high-speed and high-precision machining with orthogonal 3-axis minute line segment commands, a program should be generated by appropriately reducing the chord error (tolerance) or the block length (line segment length) based on the computer numerical control (CNC) block processing time Tb. The block processing time Tb is the duration from when the CNC decodes one block command in a program until when it controls the motors, depending on the processing power of the CNC. Accordingly, even in simultaneous 5-axis machining, it is necessary to research whether programs generated based on Tb can achieve high-speed and high-precision machining. Therefore, this study aims to realize simultaneous 5-axis machining at higher speed and precision using CNC programs with minute line segment commands based on Tb. In addition, we propose a more general identification method compared with that used in previous studies to identify Tb. Simultaneous 5-axis programs include two cases of control, namely, tool center point (TCP) control and Non-TCP control, and Tb was identified for both controls. For the machining method, using the block length based on Tb, we generated programs to machine the upper flat surface of a workpiece using simultaneous 5-axis machining while rotating the two rotary axes using a ball-end mill. We machined the workpiece and evaluated the machining speed and precision of the machined surface. We showed that simultaneous 5-axis machining with higher speed and precision can be achieved using programs based on Tb. In addition, we analyzed and considered the reasons for the higher-speed and higher-precision machining.

Optimizing Maintenance Efficiency with OEE Method

This study investigates the effectiveness of roving machines in a production environment by employing the Overall Equipment Effectiveness (OEE) methodology. High downtime of the roving machine significantly hampers production processes, leading to reduced machine performance and speed, resulting in suboptimal OEE values. Through OEE calculations, a value of 66.92% was obtained, highlighting considerable room for improvement towards achieving world-class standards. The findings underscore the necessity for targeted enhancements to mitigate machine downtime, thereby enhancing overall production efficiency and competitiveness in the manufacturing sector. Highlights : Efficient utilization of roving machines through OEE optimization is crucial for enhancing production performance. High downtime of roving machines significantly impedes production processes, leading to decreased efficiency and competitiveness. Addressing downtime issues can lead to substantial improvements in overall production efficiency, aligning operations with global standards. Keywords: Roving machine, Overall Equipment Effectiveness (OEE), Production efficiency, Downtime reduction, Manufacturing competitiveness

Development and Optimization of an Offset Spiral Tooth Fertilizer Discharge Device

Due to factors such as a small amount of fertilizer application during rice topdressing and slow machine speed, the ordinary fertilizer discharge device fails to distribute the fertilizer uniformly and accurately as required, making it difficult to meet the needs of precise rice topdressing. This research focuses on the development of an offset spiral tooth fertilizer discharge device suitable for rice topdressing. The study analyzes the amount of fertilizer discharged in one cycle, the fertilizer force, and the motion of the fertilizer particles. In order to enhance the uniformity of the fertilizer discharge device at a low speed and small volume, the discrete element method is employed to conduct experimental research on the key structural parameters that affect the one-cycle amount of discharged fertilizer and the dynamics of the fertilizer discharge device. Through single-factor tests, it was found that the angle, height, number of spiral teeth, and diameter of the fertilizer discharge wheel are closely associated with the fertilizer discharge performance. To further investigate the impact of these four parameters on the fertilizer discharge performance, a regression combination test of the four factors is conducted based on the range optimized by the single-factor tests. A multi-objective mathematical model, considering the key parameters of fertilizer uniformity coefficient, one-cycle amount of fertilizer, and fertilizer discharge torque, is established at three speeds: 20, 55, and 90 rpm. The response surface method is utilized to analyze the influence of the interaction factors on the fertilizer discharge performance. The optimal combination of the key structural parameters was determined as follows: spiral tooth angle of 35.42°, tooth height of 9.02 mm, discharge wheel diameter of 57.43 mm, and tooth amount of 9.37. The bench test results of the device, using the optimal parameter combination and a fertilizer discharge speed of 0–90 rpm, were obtained for four commonly used rice fertilizers. The maximum variation coefficient of fertilizer discharge was found to be 10.42%. The one-cycle amount of fertilizer discharge was measured to be 19.82 ± 0.72 (A Kang), 17.20 ± 0.69 (Ba Tian), 20.34 ± 0.54 (Yaran), and 14.51 ± 0.44 (granular urea). The fertilizer discharge torque remained stable. These results indicate that the achieved optimization meets the precise fertilizer application requirements and can provide technical support for precise topdressing operations.

Estimating tool life from measurements during longitudinal turning process using linear least squares

This research paper presents a procedure to estimate parameters for the modified Taylor equation using experimental measurement. The end-of-life times for each laboratory test were recorded well. The tool life has been measured by observing an abnormal change in the observed pitch of a sound from the cutting tool. The objective of this research is to understand the wear mechanisms of the insert carbide tool for different speed machining under dry condition using longitudinal turning process. The tool life equation obtained by linearizing the expanded Taylor tool life equation and solving a linear system of equations using linear least squares. In this study, both the experimental data and analytical solution show reasonable fit. The estimated tool life model simulates the measured end of tool life using the sound inspection method. An additional analysis to confirm effects of each cutting parameter on the tool life have been presented. Estimating the Tool life (TL) model using nonlinear least squares could give more accurate results which is going to be considered in the future study. The significance of this study is to save resources in the manufacturing industry by avoiding estimating tool life during turning process. Since that cause delay in the production time and waste of resources.

A composite sliding mode control with the first-order differentiator and sliding mode observer for permanent magnet synchronous machine

This paper proposes a composite sliding mode control (SMC) to optimize the tracking performance and the anti-disturbance performance of permanent magnet synchronous machine (PMSM) speed regulation systems. The differential term in the control law can magnify the measurement noise, resulting in more discontinuity. To filter out the high frequency noise and make the control law smoother, the first-order differentiator (FOD) is employed to estimate the speed error and its derivative. Since the feedforward compensation can improve the robustness of the system, a disturbance observer (DOB) based on the sliding mode observer (SMO) is designed to reinforce the dynamic performance under disturbance variation. Under the effect of the feedforward compensation, chattering can be further weakened by decreasing the switching gain appropriately. Finally, the effectiveness of the proposed methods is confirmed by various experimental results.

Determination of Factors Affecting the Quality of Sized Cotton Yarn Using Screening Experimental Method

ABSTRACT This research examines screening of the factors affecting cotton-sized yarn gain strength, elongation, stretch, size pick-up, and yarn abrasion resistance. The factors considered in this research are sizing machine parameters like sizing machine speed, squeezing roller pressure, warp yarn tension of various sizing machine zones, warp yarn twist, and viscosity of the size paste. Taguchi design with Minitab software has been used to design and analyze the results of the experiments. The study revealed that viscosity, yarn twist, sizing machine speed, and wet tension affected sized yarn gain strength significantly. Viscosity has maximum contribution to gain strength (34.57%) compared to other factors and has a positive effect on the gain strength of the sized yarn. For stretch percentage and the loss elongation of sized yarn, the wet tension is the most significant factor with 50.30% and 52.13% contribution respectively. Moreover, for the size pick-up and yarn abrasion resistance of sized yarn, the speed of the sizing machine is the most effective parameter with 44.45% and 56.29% contribution, respectively. The screening experimental result revealed the most significant factor that must be further optimized using response surface methods of experimental design.