Experiment § The process of tensile testing
The adhesive data has the physical properties of the product, such as appearance, viscosity, hardness, and sometimes elongation and tensile strength. Elongation refers to the maximum length of the colloid that can be stretched at a certain stretching speed. According to ASTM D638, the general test speed is 5、50、500mm/min. There are many different sizes and shapes of test pieces, which are selected according to different materials. Because some materials are difficult to make test pieces, they may not be suitable for this experiment. Figure 1 is a typical test piece, and our company calls it a dog bone. Figure 2 shows how the test piece is placed on the tensile machine, above and below are the fixtures, the red arrow in the middle refers to the stretcher, used to detect the elongation. After starting the test, the test piece will extend until it breaks(Figure 3-5). The maximum stress that the test piece can withstand before it breaks is the tensile strength. There is no absolute correlation between hardness, elongation, and tensile strength. When the hardness is high but the material is too brittle, the elongation is very low and will break when pulled, and the tensile strength is low. In the same way, when the formula is designed to be very tough, it may have shore D 60-70 hardness, but it can have an elongation of more than 100% when stretched.
—Author: Mr. Zhi-Hong, Wei
Activity § Final of inventory check of ERP
In the past, we had a two-year inventory day, and the whole plant stopped work to check the inventory of raw materials and products. Everwide is about to introduce the ERP system in order to achieve the purpose of unifying materials and accounts and will check the inventory on December 18. In addition to raw materials and products, laboratory raw materials and packing materials were added on the same day, therefore, manufacturing, R&D, management, and quality control departments are all involved. A month ago, the management staff planned the work content of each area, and the colleagues who did not participate in the inventory check were all arranged for education and training to guide inventory skills and organize the details of the accounts. Using the accurate data obtained from this inventory, the use of ERP in the daily cycle inventory in the future can save the time of stopping work and make work more efficient.
Knowledge § What is LOI？
LOI (Limited oxygen index) is a method to assess whether the material is easy to burn. The test method is to put a plastic test piece in a glass tube and use a flame to ignite it. The gas in the glass tube is a mixture of nitrogen and oxygen in different proportions. A certain plastic cannot be ignited by a flame in an experiment where oxygen accounts for only 18% of the mixed gas, but it can be ignited in the experiment of mixed gas with 19% oxygen and the LOI of this plastic is 19. Since the proportion of oxygen in the air is 19%, plastics with LOI lower than 19, such as POM, PP, PMMA, PS, etc., materials with LOI between 15 and 18 are very easy to ignite. As the LOI increases, the material needs to be ignited under a higher concentration of the oxygen, which means that the materials are not easy to burn. The brackets represent the LOI of different materials, and the general value is above 27, indicating that it is non-flammable: PBT(23)、PC(27)、PPO(31)、PVC(45).
Living § Fenrui Historic Trail One Day Tour
The Fenrui Historic Trail is about 7 kilometers long from Fenqi Lake to Ruili in Alishan. Yexu’s family and I traveled like ancients in the sunny early winter. At 9:30, we took the Alishan train to depart. Although the parking space was very small, everyone was very happy because the train was very famous and difficult to buy tickets. The car didn’t travel for long, and suddenly there was a harsh brake sound from the railroad tracks, followed by a collision, and the little train stopped in a deserted grassland. Everyone was startled in a cold sweat and instinctive craned their necks to look out, the situation was that the car broke out of the road and hit a small train (Figure 1). The captain told passengers not to get off the bus and waited quietly for the police to come to the notarization. It took about an hour to arrive at Fenqi Lake, which was two hours lower than originally planned. We set off from the entrance of the mountain, intending to speed up, otherwise, it will be dark when the sun goes down (Figure 2). Starting at an altitude of 1400 meters, the whole section of the road is uphill. We climbed up the stairs and inadvertently found that we were already in a dense bamboo forest (Figure 3). After climbing to the 1600- meter peak, we took a short rest by the guardrail of the Chanye Road and then went in the direction of Ruili. The sky was gradually darkening, and the sleeper trails were steep and muddy, which made people fearful. Yexu fell and her son was so scared that he was crying, it took a long time for the four adults to comfort him before he stopped crying. We walked into the depths of the trees, the slight sunlight only allowed us to recognize the road conditions. When we walked to an empty place, we saw the afterglow of the setting sun shining in the sky and the beautiful scenery of the distant mountains becoming golden (Figure 4). After we trot for the last 200 meters, we only slowed down when we saw the mountain pass. At this time, Ruili in the mountain was already lit up.
—Author: Su-hui, Chen
