Performance analysis in WEDM of titanium grade 6 through process capability index

2020 ◽  
Vol 17 (1) ◽  
pp. 144-151
Author(s):  
Himadri Majumder ◽  
Kalipada Maity
Keyword(s):  
Surface Roughness ◽  
Process Capability ◽  
Process Capability Index ◽  
Average Surface Roughness ◽  
Content Type ◽  
Average Surface ◽  
Process Capability Analysis ◽  
Capability Index ◽  
Capability Analysis ◽  
Titanium Grade

Purpose The purpose of this study aims to obtain excellent products, consistent investigation and manufacturing process control which are the preconditions that organizations have to consider. Nowadays, manufacturing industry apprise process capability index (Cpi) to evaluate the nature of their things with an expect to enhance quality and also to improve the productivity by cutting down the operating cost. In this paper, process capability analysis was applied during wire electrical discharge machining (WEDM) of titanium grade 6, to study the process performance within specific limits. Design/methodology/approach Four machine input parameters, namely, pulse ON time, pulse OFF time, wire feed and wire tension, were chosen for process capability study. Experiments were carried out according to Taguchi’s L27 orthogonal array. The value of Cpi was evaluated for two machining attributes, namely, average surface roughness and material removal rate (MRR). For these two machining qualities, single response optimization was executed to explore the input settings, which could optimize WEDM process ability. Findings Optimum parameter settings for average surface roughness and MRR were found to be TON: 115 µs, TOFF: 55 µs, WF: 4 m/min and WT: 6 kg−F and TON: 105 µs, TOFF: 60 µs, WF: 4 m/min and WT: 5 kg−F. Originality/value Process capability analysis constantly checks the process quality through the capability index keep in mind the end goal to guarantee that the items made are complying with the particulars, providing data for product plan and process quality enhancement for designer and engineers, giving the support to decrease the cost of item failures.

scholarly journals Process Capability and Average Roughness in Abrasive Water Jet Cutting Process of Stainless Steel

2018 ◽  
Vol 8 (3) ◽  
pp. 2931-2936
Author(s):  
M. Boujelbene
Keyword(s):  
Stainless Steel ◽  
Process Capability ◽  
Water Jet ◽  
Process Capability Index ◽  
Abrasive Water Jet ◽  
Process Capability Analysis ◽  
Capability Index ◽  
Water Jet Cutting ◽  
Abrasive Water Jet Cutting ◽  
Capability Analysis

Process capability analysis is frequently employed to evaluate if a product or a process can meet the customer’s requirement. In general, process capability analysis can be represented by using the process capability index. Until now, the process capability index was frequently used for manufacturing processes with quantitative characteristics. However, for a process with qualitative characteristic like cutting surface, the data’s type and single specification caused limitations of using the process capability index. Taguchi developed a surface quality by abrasive water jet cutting or quadratic quality loss function to address such issues. In this study, we intend to construct a measurable index which incorporates the process capability index philosophy concept to analyze the process capability with the consideration of the qualitative surface roughness. The manufacturers can employ the proposed index to self-assess the process capability. The objective of this study was to examine the effects of abrasive water jet machining variables like cutting speed of the stainless steel material. The roughness of the varied surface through the cut depth was also measured and determined as a process capability index of 3 zones machined surface.

Optimization of Machining Condition in WEDM for Titanium Grade 6 Using MOORA Coupled with PCA — A Multivariate Hybrid Approach

2017 ◽  
Vol 16 (02) ◽  
pp. 81-99 ◽  
Author(s):  
Himadri Majumder ◽  
Kalipada Maity
Keyword(s):  
Surface Roughness ◽  
Process Parameters ◽  
Hybrid Approach ◽  
Cutting Speed ◽  
Kerf Width ◽  
Average Surface Roughness ◽  
Average Surface ◽  
Titanium Grade ◽  
Pulse On Time ◽  
Pulse Off Time

This paper represents a multivariate hybrid approach, combining Multi-Objective Optimization on the basis of Ratio Analysis (MOORA) and Principal Component Analysis (PCA) to optimize different correlated responses during Wire Electrical Discharge Machining (WEDM) process of titanium grade 6. The response parameters selected are the average cutting speed, average Kerf width and average surface roughness (Ra). All of them have been studied in terms of pulse-ON time, pulse-OFF time, wire feed and wire tension. As indicated by Taguchi’s signal-to-noise ratio, the optimum process parameters were achieved for the desired average cutting speed, average Kerf width and average surface roughness, respectively. At last, the optimum combination of process parameters was validated by affirmation test which gave considerably improved various quality characteristics. Confirmation test outcome revealed that multivariate hybrid approach MOORA coupled with PCA was a competent strategy to decide available cutting parameters for a desired response quality for WEDM of titanium grade 6.

scholarly journals PROCESS CAPABILITY ANALYSIS PADA NUT (STUDI KASUS: PT SANKEI DHARMA INDONESIA)

2017 ◽  
Vol 12 (2) ◽  
pp. 137
Author(s):  
Helena Sisilia R. S. ◽  
Hendy Tannady
Keyword(s):  
Process Control ◽  
Statistical Process Control ◽  
Process Capability ◽  
Statistical Process ◽  
Process Capability Analysis ◽  
Capability Index ◽  
Inside Diameter ◽  
Capability Analysis ◽  
Improved Performance ◽  
A Company

PT Sankei Dharma Indonesia merupakan perusahaan yang bergerak di bidang otomotif. Salah satu produk yang dihasilkan adalah nut (berfungsi sebagai dudukan kabel sensor). Proses nut dianggap critical to quality, dimana hasil dari proses memperhatikan inside diameter nut yang dihasilkan PT A, PT B, dan PT C. Peningkatan kinerja proses dilakukan dengan menggunakan process capability yang merupakan salah metode dari Statistical Process Control. Hasil dari penelitian menunjukkan bahwa process capability pada inside diameter PT B berjalan dengan tidak sesuai, di mana nilai capability index Cp = 0.57, Cpl = 0.58, Cpu = 0.56, Cpk = 0.56, dan Cpm = 0.54. Sedangkan process capability pada inside diameter PT A dan PT C tergolong sangat memuaskan. Di mana nilai capability index PT C Cp = 2.34, Cpl = 2.37, Cpu = 2.30, Cpk = 2.30, dan Cpm = 2.26. Dan nilai capability index PT A Cp = 1.77, Cpl = 1.79, Cpu = 1.75, Cpk = 1.75, dan Cpm = 1.86. AbstractPT Sankei Dharma Indonesia is a company engaged in the automotive field. One of the resulting product is a nut (functioning as a sensor cable holder). Nut process is considered critical to quality, which result from the attention generated inside diameter nut PT A, PT B, dan PT C. Improved performance of process is done by using process capability, which is one method of Statistical Process Control. Results from the study showed that the process capability to the inside diameter of the PT B running is not appropriate, in which the value of capability index Cp = 0,57; Cpl = 0,58; Cpu = 0,56; Cpk = 0,56, dan Cpm = 0,54; While the process capability to inside diameter PT A and PT C as very satisfactory. Where the value of capability index PT C Cp = 2.34, Cpl = 2.37, Cpu = 2.30, Cpk = 2.30, dan Cpm = 2.26. And the value of capability index PT A Cp = 1.77, Cpl = 1.79, Cpu = 1.75, Cpk = 1.75, dan Cpm = 1.86.

Some new methods for comparing the capability of two processes using process capability index Cpm

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Michael Perakis
Keyword(s):  
Confidence Intervals ◽  
Practical Implication ◽  
Simulated Data ◽  
Process Capability ◽  
Process Capability Index ◽  
Small Samples ◽  
Content Type ◽  
Capability Index ◽  
New Methods ◽  
Practical Implications

PurposeThe purpose of the paper is the construction of confidence intervals for the ratio of the values of process capability index Cpm for two processes. These confidence intervals can be used for comparing the capability of any pair of competitive processes.Design/methodology/approachTwo methods for constructing confidence intervals for the ratio of the values of process capability index Cpm for two processes are proposed. The suggested techniques are based on a two-step approximation of the doubly non-central F distribution. Their performance is tested via simulation.FindingsThe performance of the suggested techniques seems to be rather satisfactory even for small samples, as illustrated through the use of simulated data.Practical implicationsThe practical implication of the suggested techniques is that they can be implemented in real-world applications, since they can be used for comparing the capability of any pair of competitive processes.Originality/valueThe paper presents two new methods for constructing confidence intervals for the ratio of the values of process capability index Cpm for two processes.

A new mixed repetitive group sampling plan based on the process capability index for product acceptance

2018 ◽  
Vol 35 (2) ◽  
pp. 463-480 ◽  
Author(s):  
Balamurali Saminathan ◽  
Usha Mahalingam
Keyword(s):  
Process Capability ◽  
Process Capability Index ◽  
Sampling Plan ◽  
Optimal Parameters ◽  
Sampling Plans ◽  
Content Type ◽  
Practical Applications ◽  
Capability Index ◽  
Unknown Variance ◽  
Repetitive Group Sampling

Purpose The purpose of this paper is to propose a new mixed repetitive group sampling (RGS) plan based on the process capability index, Cpk, where the quality characteristics of interest follow the normal distribution with unknown mean and unknown variance. Tables are constructed to determine the optimal parameters for practical applications for both symmetric and asymmetric fraction non-conforming cases. The advantages of this proposed mixed sampling plan are also discussed. The proposed sampling plan is also compared with other existing sampling plans. Design/methodology/approach In order to determine the optimal parameters of the proposed mixed RGS plan based on Cpk, the authors constructed tables for various combinations of acceptable and limiting quality levels (LQLs). For constructing tables, the authors followed the approach of two points on the operating characteristic (OC) curve. The optimal problem is formulated as a non-linear programming where the objective function to be minimized is the average sample number (ASN) and the constraints are related to lot acceptance probabilities at acceptable quality level and LQL under the OC curve. Findings The proposed mixed RGS plan will be a new addition to the literature of acceptance sampling. It is shown that the proposed mixed plan involves minimum ASN with desired protection to both producers and consumers compared to other existing sampling plans. The practical application of the proposed mixed sampling plan is also explained with an illustrative real-time example. Originality/value In this paper, the authors propose a new mixed RGS plan based on the process capability index Cpk, where the quality characteristic of interest follows the normal distribution with unknown mean and unknown variance. Tables are constructed to determine the optimal parameters for practical applications. The proposed mixed sampling plan can be used in all production industries. This kind of mixed RGS plan is not available in the literature.

Optimization of machining parameters for abrasive water jet drilling of carbon fiber-reinforced polymer composite material using Taguchi method

2019 ◽  
Vol 92 (2) ◽  
pp. 128-138 ◽  
Author(s):  
Meltem Altin Karatas ◽  
Hasan Gokkaya ◽  
Muammer Nalbant
Keyword(s):  
Surface Roughness ◽  
Composite Material ◽  
Water Pressure ◽  
Aerospace Industry ◽  
Machining Parameters ◽  
Average Surface Roughness ◽  
Taguchi Optimization ◽  
Content Type ◽  
Average Surface ◽  
Cfrp Composite

Purpose The aim of this paper is to optimize the machining parameters to obtain the smallest average surface roughness values during drilling of the carbon fiber-reinforced polymer (CFRP) composite material with abrasive water jet (AWJ) and analyze the damage of the delamination. Design/methodology/approach CFRP composite material had been fabricated having fiber orientations frequently used in the aerospace industry (0°/45°/90°/−45°). Three different stand-off distances (1, 2 and 3 mm), three different water pressures (1,800, 2,800 and 3,800 bar) and three different hole diameters (4, 8 and 12 mm) were selected as processing parameters. The average surface roughness values were obtained, and delamination damage was then analyzed using Taguchi optimization. Drilling experiments were performed using the Taguchi L27 orthogonal array via Minitab 17 software. The signal/noise ratio was taken into account in the evaluation of the test results. Using the Taguchi method, the control factors giving the mean surface roughness values were determined. Analysis of variance was performed using the experimental results, and the effect levels of the control factors on the average surface roughness were found. Findings It was found that water pressure and hole diameter had a higher effect on average surface roughness, while water pressure and stand-off distance were effective on delamination. Practical implications Owing to their excellent thermal and mechanical properties, the CFRP composite materials show greater potential for their applications in aircraft and aerospace industry. Originality/value The novel approach is to reduce cost and spent time using Taguchi optimization as a result of AWJ drilling the material in this fiber orientation ([0°/45°/90°/−45°]s, which is often used in the aerospace industry).

Process capability analysis of fused deposition modelling for plastic components

2014 ◽  
Vol 20 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Rupinder Singh
Keyword(s):  
Process Capability ◽  
Dimensional Accuracy ◽  
Fused Deposition Modelling ◽  
Economic Point ◽  
Content Type ◽  
Process Capability Analysis ◽  
Fused Deposition ◽  
Capability Analysis ◽  
Measuring Machine ◽  
Plastic Components

Purpose – The purpose of the present study is process capability analysis of fused deposition modelling (FDM) process as rapid pattern making (RDPM) solutions for plastic components. Design/methodology/approach – Starting from the identification of component, prototypes with ABS plastic material were produced and dimensional measurements were made with coordinate measuring machine (CMM). Some important mechanical properties were also compared to verify the suitability of the components. Findings – The study highlighted the best settings of orientation, support material quantity for the selected component as a case study on FDM machine from dimensional accuracy and economic point of view as RDPM solution for plastic components. Practical implications – This process ensures rapid production of statistically controlled pre-series technological prototypes and proof of concept at less production cost and time. Final components produced are acceptable as per ISO standard UNI EN 20286-I and DIN16901. Originality/value – The results of the study suggest that FDM process lies in ±4.5 sigma (σ) limit in regard to dimensional accuracy of plastic component is concerned and may be gainfully employed as RDPM solution for bio-medical applications.

Development of the yield-based process capability index, C py , to flexibly and accurately measure conformance

2016 ◽  
Vol 33 (7) ◽  
pp. 882-899
Author(s):  
George N Kenyon ◽  
R. Samual Sale ◽  
Kurt Hozak ◽  
Paul Chiou
Keyword(s):  
Process Capability ◽  
Process Capability Index ◽  
Process Data ◽  
Process Variability ◽  
Content Type ◽  
Attribute Data ◽  
Capability Index ◽  
Sigma Level ◽  
Multiple Characteristics ◽  
Improved Accuracy

Purpose – The purpose of this paper is to develop an yield-based process capability index (PCI), C py , to overcome the shortcomings of existing PCIs that limit their use and lead to inaccurate measures of quality conformance under a variety of common conditions. Design/methodology/approach –C py is developed conceptually to flexibly and accurately reflect conformance and then used to numerically measure inaccuracies of C pk . Findings –C py overcomes many of the problems associated with existing PCIs, including C pk . The degree of process distribution non-normality, level of quality (the sigma level), and whether the process is centered or shifted left or right affect the direction and size of process capability error produced by C pk . The accuracy of C pk can be greatly affected by process data that deviate even slightly from normality. Practical implications –C py offers numerous advantages compared to existing PCIs. It accurately reflects process conformance regardless of the process distribution. It is applicable even if the process has multiple characteristics and with both variable and attribute data. Its calculation is relatively simple and the necessary data for it are likely already captured by most organizations. Originality/value – The main contributions are the development of a new PCI, C py ; a conceptual analysis of its advantages; and a numerical analysis of the improved accuracy of C py as compared to C pk for shifted and non-shifted process means for normal, nearly normal, and highly non-normal distributions over a range of process variability levels.

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