Journal of Manufacturing & Management Technology

Cost Reduction in Automotive Parts Production by Applying Sampling Standards

Mon, 30 Jun 2025 00:00:00 +0700

This study aims to improving the weld seam inspection sampling process in an automotive parts manufacturing facility, particularly for TAO model components. The improvement involves implementing the MIL–STD–105E sampling plan to replace the previous non–standard inspection method. Initially, three samples per lot were inspected, leading to high inspection costs due to the destructive testing nature, totaling 167,040 baht annually. The improvement strategy included historical data analysis, control chart implementation, and adjustment of the sampling plan. Results from the control charts indicated that the production process remained within control limits, allowing the application of switching rules from normal to reduced inspection. By adopting the MIL–STD–105E plan and negotiating acceptable risk levels with customers, the number of samples per lot was reduced from three to two. Consequently, annual inspections decreased from 1,392 to 1,008 pieces, cutting inspection costs to 120,960 baht—resulting in savings of 77,310 baht per year. These findings confirm that the process remains under statistical control while significantly reducing inspection costs in quality control.

Facility Layout Improvement Using Systematic Layout Planning and Multi-Criteria Decision Making: A Case Study in the Electronics Industry

Jaruwan Deesamer, Somkiat Phudee, Pattra Pooprang — Mon, 30 Jun 2025 00:00:00 +0700

This research aims to improve the factory layout to accommodate the addition of two new production lines for printed circuit board assembly (PCBA). An initial assessment identified that the existing layout could not effectively support expansion due to inadequate workspace and disrupted process flow in Production Line, resulting in excessive material handling and reduced production efficiency. To address these issues, three layout alternatives were designed using Systematic Layout Planning (SLP) and evaluated with Analytic Hierarchy Process (AHP) based on material distance, safety, flexibility, and space utilization. Alternative 3 was selected as optimal, reducing material–handling distance by 40%.

Guidelines for Improving the Efficiency of Drinking Water Production Process A Case Study of Drinking Water Plant in Nakhon Phanom Province

Wirekha Khamjan, Phornchanok Kopon, Sakda Khamjan — Mon, 30 Jun 2025 00:00:00 +0700

The paper presents methods to enhance the efficiency of drinking water production processes through a case study of a drinking water plant in Nakhon Phanom Province. Use fishbone diagrams along with the Why-Why Analysis. To find the cause of the problem, 2 main problems need to be urgently resolved. The first problem was a delay in bottling drinking water due to two employees working intermittently, which resulted in unemployment. Therefore, the principles of Man-Machine Chart analysis are used to solve this problem. This approach allows us to increase our employees' working hours. We reduced the cycle time from 9.32 minutes to 7.76 minutes, resulting in a 1.56-minute reduction per cycle. Additionally, the average efficiency of employees working increased from 49.99% to 60.12%. The second problem is filling bottles in quantity. They are not equal. It is caused by the irregular distribution of water from the dispenser. Adjusted 24 water supply valves and measured timers. As a result, the time required to add drinking water increased from the original 14 seconds to 12 seconds, accounting for a 14.29 percent reduction.

Reducing Changeover Time in the Plastic Injection Process: Case Study

Mon, 30 Jun 2025 00:00:00 +0700

This research focuses on reducing the changeover time of the plastic injection process and analyzing the economic benefits of improvement. It starts with identifying and analyzing the problems that occur in the changeover process systematically, using the cause-and-effect mapping tool to identify the causal factors and the Why-Why Analysis to evaluate the root causes of the problems. The work correction and improvement approach is developed based on the ECRS principle. The results of the operation show that the changeover time is significantly reduced from 3,960 seconds to 3,582 seconds, which is a reduction of 378 seconds, or 9.54 percent. In addition, the economic analysis indicates that labor costs can be reduced by 348,872.8 baht per year, and the project has a break-even point of only 7 days. This study demonstrates the effectiveness of applying the work and time study to increase productivity and create tangible economic benefits.

Investigation of the Effects of Welding Path Patterns on the Mechanical Properties of 6061 Aluminum Alloy in GMAW Using a Robotic Welding Arm

Mon, 30 Jun 2025 00:00:00 +0700

This research aims to investigate the effects of welding path patterns on the mechanical properties of aluminum alloy 6061 under an automated welding process. The study utilizes a robotic welding arm integrated with welding power source, operating under the Gas Metal Arc Welding (GMAW) process, also known as Metal Inert Gas (MIG) welding. The test specimens are aluminum alloy 6061 plates with dimensions of 100 × 200 × 4 mm. Constant welding parameters are maintained, including a welding current of 180 A, shielding gas flow rate of 12 L/min, wire feed speed of 6 m/min, and travel speed of 0.5 m/min. Three distinct welding path patterns are examined: linear (without weaving), zigzag weaving, and circular weaving. Mechanical properties are evaluated using the Vickers Hardness Test and Tensile Test. The results indicate that the circular weaving pattern yields the highest average weld hardness of 70.38 HV and the highest tensile strength of 154.74 MPa. The zigzag weaving pattern follows with a hardness of 64.10 HV and tensile strength of 141.39 MPa, while the linear pattern produces the lowest values at 66.94 HV and 135.44 MPa, respectively. These findings demonstrate that the welding path pattern significantly influences the mechanical behavior of the weld in aluminum alloy 6061. The research findings can be used as a guideline for developing control strategies in robotic welding processes within the industrial sector to enhance the efficiency and quality of welded components.

Development of Waste Data Monitoring and Analysis System in Production Process

Mon, 30 Jun 2025 00:00:00 +0700

This study presents the development of an integrated digital system for waste data monitoring and analysis system for the production process of a case study company. The system aims to reduce working time for operators in data recording and make the process more user–friendly, while allowing management to access information in real–time. The system architecture integrates three main modules Google Form and Google Sheet software to create data collection forms, integrated with Looker Studio for data summarization and analysis. Experimental results demonstrated the system successfully reduced the operation process time from an average of 30.33 minutes to 10.30 minutes, representing a 66.04% improvement in operational efficiency compared to the previous method.

Analysis of Water Jet Cutting Parameters on Surface Roughness of SKD 11 Steel

Mon, 30 Jun 2025 00:00:00 +0700

This research aims to investigate the effects of various factors, including water pressure, cutting speed, stand–off distance, and abrasive type, on the surface roughness of SKD 11 tool steel in the abrasive water jet cutting process. The study applied the Box–Behnken Design (BBD) for experimental design and employed Analysis of Variance (ANOVA) for statistical analysis. The results indicated that all four factors significantly influenced surface roughness (p–value < 0.05), with surface roughness values ranging between 3.21 and 4.75 micrometers. The optimal conditions for achieving the lowest surface roughness were a water pressure of 35,000 Psi, a cutting speed of 20 mm/min, a stand–off distance of 1.64 mm, and the use of Garnet II Abrasive. The developed model demonstrated high accuracy with an R² of 88.36% and an Adjusted R² of 81.03%. The findings of this study can be applied as guidelines for selecting appropriate parameters in abrasive waterjet cutting processes to control surface quality and enhance production efficiency.

Microscale Mechanical Properties of (1–x)Sr(Fe0.5Nb0.5)O3–xBiFeO3 Ceramics

Ratabongkot Sanjoom, Yingyos Thipsrirach, Thiti Mhoraksa, Kamonpad Mansilp — Mon, 30 Jun 2025 00:00:00 +0700

This study investigates the micro–scale mechanical behavior and crystal structure of (1–x)Sr(Fe_0.5Nb_0.5)O₃–xBiFeO₃ ceramics (x = 0.00, 0.01, 0.05, 0.10) synthesized via solid–state reaction. X–ray diffraction analysis confirmed a pure orthorhombic perovskite phase for x ≤ 0.05, whereas the x = 0.10 composition exhibited a secondary phase. Archimedes density measurements showed an increase from 4.28 g/cm³ (x = 0.00) to 5.53 g/cm³ (x = 0.10). Vickers microhardness testing revealed a maximum hardness of 4.80 GPa at x = 0.05, which decreased to 3.04 GPa at x = 0.10 due to secondary phase formation and microstructural porosity. The BiFeO₃ content should be limited to x ≤ 0.05 to prevent the emergence of undesirable secondary phases and porosity that compromise mechanical performance. Ceramics with optimized BiFeO₃ loading are therefore well suited for micro energy harvesting devices, microscale pressure sensors, and micro–actuators requiring high durability at the microscale.

A study of Mechanical and Thermal Properties of Louver Panel Product Plastic Composite for Architectural Applications

Budsaba Karoonsit, Patiparn Ninpetch, Kraisuk Boonpradit, Chaiyapat Rammarat — Mon, 30 Jun 2025 00:00:00 +0700

Plastic Composite (PC) is a material extensively utilized in the production of louver panels for architectural and decorative purposes. It enhances the aesthetics of both interior and exterior buildings due to its lightweight, strength, durability, and environmental friendliness. Therefore, studying the material properties of louver panels made from PC is essential to select the most suitable and efficient material for architectural applications. This research focuses on a comparative study of the mechanical and thermal properties of three types of louver panel product plastic composite according to the standards of the American Society for Testing and Materials (ASTM). Each case was evaluated with five test specimens. The results revealed that PC I has the highest hardness, tensile strength, and elongation of 56 Shore D, 13.08 MPa, and 2.14%, respectively, indicating good strength and toughness. PC I also demonstrated better impact resistance and bending resistance than PC II and PC III, which exhibited lower impact resistance and flexural strength. In the deflection temperature test, the testing results indicated that PC I, PC II, and PC III manifested slight differences in deflection temperature, but no significant differences were observed. Moreover, the thermal analysis showed that thermal properties and bond dissociation energy values of the materials PC I, PC II, and PC III exhibit no significant differences. The findings from this study can provide guidelines for the development of high–quality louver panels that effectively meet both aesthetic and durability requirements.