Case Study Development of Welding Machine for Sterling Silver Jewelry Parts With 500-amp electrical arc system for welding closing porous jewelry after casting. The problem can be solved by welding closing porous or by the jewelry. It is an alternative to repairing the work piece. The efficiency of electrical arc welding equipment can be repaired to a certain extent. Based on the results of the experiments the welding and repairing porous porcelain parts were rated at 500 amperes by random sampling of 4 time slots 5 seconds 10 seconds 15 seconds and 20 seconds. Examine the most appropriate porous or porous workpiece for 20 seconds with 18 complete workpieces capable of sealing or milling. A good percentage of 90 percent of the performance of an electrical arc welding machine for welding sealing or cutting.

The results of the study on the optimum temperature for baking soda extinguishers were investigated. B9R-3-EMERALD Using brass material in experiments. It was found that the temperature of 750˚C was good for 48% of the workpiece 52% was found that the workpiece was damaged at the surface of the work very porous at the surface. Caused by the heat of metal water pouring into contact with the moisture of the mold resulting in gas. High temperature of metal water Or eliminate gas in metal water is not exhausted. The workpiece is not suitable at a temperature of 800 ° C with a good workpiece of 76%. The workpiece loses 24%. The workpiece loses less punch at the lower porosity as well at 750˚C in temperature. 850˚C workpiece 96% workpiece 4% workpiece the workpiece is almost out. It is less than 750˚C and 800˚C at porosity. And at 900˚C the workpiece is 100% of the workpiece 0%. The workpiece is the best. Workpiece waste from the minimum. The test results make the temperature at 900 ° C is the cleanest casing temperature

This Research is to Study the Development of 6k White Gold Low Alloys Metal for Jewelry Production The Optimum Conditions for Casting Jewelry and Jewelry were Investigated. The Results of the Experiments Show that the Chemical Composition of the 8k White Gold Low Alloys is Slightly Different when Compared with XRF (X-ray Fluorescence Spectrometers) Pre-and Post-Melting Quantities The Heat of the Test Specimen was found to be 33.33%Au+50.67%Ag+10%Cu+5%Zn+1%Sn33.33%Au+50.67% Ag+8% Cu+7%Zn+1%Sn and 33.33%Au+50.67%Ag+8%Cu+8%Zn+0%Sn It is Found that the Heat from the Beginning to the Level of Change before the Liquid is used the Average Temperature of 458.9 – 326.3 Degrees Celsius Respectively 33.33%Au+50.67%Ag+8%Cu+7%Zn+1%Sn It is the Formula that Gives the Lowest Value of Liquid State Change from 326.3 Degrees Celsius to the Best Value of this Experiment. Suitable for use in the Manufacture of Jewelry due to its Melting Ability for Molding. Melting for Molding and Formed by Hand. The Amount of Zinc(Zn) may be an Important Factor in the Variation which is Directly Proportional to the Maximum Increase in the Final order of 7 Percent

The purposes this research were: 1) to develop the activity packages on home textile pillow products forming process for textile product design students division the efficiency of 80/80 2) to compare academic achievement of textile product design students academic calendar 2018 before and after the experiment using the activity packages on home textile pillow products forming process 3) to study satisfaction of students toward the activity packages on home textile pillow products forming process. The sample consisted of 20 students who studied textile product design in the academic year 2018 at Rajamangala University of Technology Phra Nakhon. They were selected by purposive sampling. The research instruments were the activity packages on home textile pillow products forming process the achievement test and a satisfaction questionnaire. The data were analyzed by percentage mean standard deviation and t-test for dependent samples.The results of the study were as follows: 1) the efficiency of the activity packages on home textile pillow products forming process for textile product design students was obtained 84.65/82.50 higher than a predetermined threshold 80/80 2) academic achievement of home textile pillow products forming process for textile product design students was significantly higher than before the experiment using the activity packages on home textile pillow products forming process at the 0.5 level 3) the satisfaction of Textile Product Design students using the activity packages on home textile pillow products forming process was at the high level.

This Research is a Development of 8k White Gold low Alloy Metal Components for Jewelry Pieces. By Study and Analyze the Influence of Silver Alloy Gold Alloy Bronze Alloy Zinc Alloy and Tin Alloy. Which Affect Microstructure and Mechanical Properties. (The Different of Color Scales) And Resistance Behavior of Lowered 8k White Gold Alloy in Varies Ratio. The Results Showed that Tests and Analysis to Find the Quantities of Elements has found out that Chemical Components of 8k White Gold Low Alloy Metal had a Little Different Quantities when Compared Between Before and After Centrifugal Casting Process. The Tests and Analysis Results of Mechanical Properties of Test Pieces Showed that the Hardness and Tensile Strength of 8k White Gold Low Alloy Metal with Mixture of 33.33%Au+50.67%Ag+10%Cu+5%Zn+1%Sn had Minimum Ultimate Tensile Strength Equal 0.54 kN/mm2 Minimum Elongation Percentage of 55% and Maximum Hardness of 137.0 HV. The Test Results also Show that the Mechanical Properties of the Material are Brittle Material. When Perform a Forming Process the Pieces will be Easily Broken which was Meant that the Forming Process would be Difficult. But The Color Level of the Test Pieces at this Composite Ratio had the Best Metal Color Level. The Brightness L * = 74.87 was a * = -0.89 b * = 13.74 and the Value of ΔE with the Lowest Color Difference Level of 1.35. Compared to other Varies Ratio. It Showed that 8k White Gold Low Alloy Metal Test Pieces were Very Green and Came out Slightly Yellow Compared to the Blue Line that Approached the Standard Line. These Properties were the Physical Properties Required in 8k White Gold Low Alloy Metal Jewelry Pieces Production. Also there were the Results of 8k White Gold Low Alloy Metal in Two Formulas 8k 33.33%Au+50.67%Ag +8%Cu+7%Zn+1%Sn 33.33%Au+50.67%Ag+8%Cu+8%Zn+0%Sn. These Formulas had Tensile Strength in the Range of 1.10 0.60 kN /mm2 Elongation Percentage in the Range of 70 61% and Hardness of 115.6 123.3HV Respectively. The Results of the Mechanical Properties Test of the Test Pieces Showed that 8k White Gold Low Alloy Metal 33.33% Au+50.67%Ag+8%Cu+7%Zn+1%Sn has Similar Tensile Strength but Maximum Elongation Percentage of 70% and Minimum Hardness of 115.6HV. Which was Suitable for Forming Because of good Ductility and Stretchness Properties (Ductile Material). Forming would be Easy. These were Good Mechanical Properties for Forming Precious Metals.