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• We Introduce Attentions of Plastic Mold Parts

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  Plastics Guide bush are much softer and less rigid than metals. The sectional shapes and sizes should be carefully chosen in this regard. If needed, a high section modulus can be achieved using principles similar to that used in I-beams and tubes. Curves can be used to stiffen large, flat surfaces. Venetian blinds, for example, have very thin slats that are gently curved despite their rigidity. We will use a garden tractor as an example of a simple design approach by comparing a sheet metal and a plastic hood. By reinforcing with fibers or particles, it is also possible to achieve lightweight and stiff designs. An individual process for shaping or molding a part is often determined by its overall shape and thickness. When a particular process is selected, the parts and dies should be designed so that they won’t present difficulties in generating the proper shapes, in controlling dimensions, or finishing the surfaces. Since the properties of thermoplastics are not as stiff as metals, dimensional tolerances (especially for thermoplastics) are not as tight as with metalworking. Injection molding, for instance, has much smaller dimension tolerances than thermoforming. It is crucial to control the flow of materials in the mold cavity when casting metals and alloys. When a polymer is processed by extrusion, thermoforming, or blow molding, the impact of molecular orientation should also be taken into consideration. The shape should not be changed in an abrupt way, or with large variations in area and section thickness. As an example, the top piece in FIG. 1 shows sink marks (pull-in). Thicker sections solidify last, thus the reason for 19.31c. Furthermore, plastic parts, as well as metal ones, tend to have porosity as a result of contraction in larger cross sections, which affects them negatively. On the other hand, if the part is too thin, it may be more difficult to remove it from the mold after shaping. Low elastic moduli of plastics further require proper shape selection for component stiffness, especially when a significant amount of material saving is essential. The considerations for designing polymer castings and forgings are similar to those that apply to the design of metal castings, as is the requirement for drafts (typically below one degree for polymers) for removing parts from molds. A general rule of thumb is that the recommended thickness for small parts is 1mm (0.04 in.) and the thickness for large parts is 3mm (0.12 in.). If you want to choose Guide bush, contact us immediately!
• There Is A Brief History of Plastic Injection Mold Parts

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  When you think of the great inventions of modern history you probably think of automobiles, airplanes, computers, and other revolutionary innovations. While these developments are vital, have you ever considered the multifaceted manufacturing processes, materials, and design applications their production entails? Many people are unaware of today’s invaluable manufacturing methods and tools, but without them, industrial innovations and new-age technological devices would not exist. Plastic injection molding is a perfect example. Plastic has emerged as one of the most critical mediums in modern manufacturing as it offers affordable, high-quality production runs and durable, corrosion-resistant parts and products. Plastic injection Mold parts technology has only enhanced the design and application capabilities of plastic materials. The modern world would look drastically different without plastic injection molding. Let’s dig a bit deeper into it’s history. The Start of Plastic Injection Molding Plastic injection molding was invented in the late 19th century, with the first molding machine patented in 1872 by two brothers, John and Isaiah Hyatt. While the device was simple by today’s standards, it quickly led to the growth of a nascent plastic manufacturing industry, where combs, buttons, and other simple articles were molded in plastic. In 1903 two German scientists, Arthur Eichengrun and Theodore Becker, created soluble forms of cellulose acetate; this was significantly less flammable than previous alternatives. While the 1930’s were a dark time for many people, for the plastics manufacturing industry it was a decade of innovation. Many of the most popular thermoplastics, such as polyolefins, polystyrene, and polyvinyl chloride (PVC) were invented during this time. World War Two and the Brave New World World War Two reshaped human history. The Second Great War popularized airplanes, led to dramatic advancements in automotive technology, and enhanced the United States war manufacturing economy that would later power the first stage of the post-war industrial revolution. Regarding plastics, this period also elicited a high demand for inexpensive, mass-produced materials. This demand following World War II was in part a result material shortages. For example, rubber production was disrupted by the war across Asia and attacks on shipping lanes. Tanks and other war applications created a huge demand for metal. Plastics stepped in to fill the gap, providing an affordable substitute. As plastics gradually popularized, so too did plastic injection molding. It’s effectiveness to this era was primarily attributed to efficient, affordable, large-scale manufacturing. Throughout the post-war period plastics remained popular. As business leaders recognized the tremendous cost benefits over rivaling materials, global supply chains were reevaluated, and plastics became firmly entrenched in the mid-20th century’s economy and manufacturing processes. James Watson Hendry and the Modern Plastic Injection Molding Industry By 1946, American inventor James Watson Hendry built the world’s first extrusion screw injection machine. Using a rotating screw, Hendry was able to better control the injection process itself. This dramatically increased the quality of the products produced. Hendry wasn’t done after creating the extrusion screw injection machine. Far from it. Hendry went on to develop the first gas-assisted injection molding process, a pivotal innovation that allowed for the creation of long, complex, hollow products. With materials providing increased strength and reduced weight, plastic production had overtaken steel production by the 1970s. By 1990 aluminum molds had become a manufacturing trend; a faster, cheaper production alternative to steel molds. Hendry is one of the most important names in manufacturing history. Without his inventions, plastic injection molding would not be as advanced as it is today. The Current State of Plastic Injection Molding Today, the opportunities provided by plastic injection molding are implemented by essentially every manufacturing sector; electronics, automotive, home appliances, housewares, you name it. Plastic Injection Molding is an affordable and effective method of producing high-quality parts and products. The technology used today is quite similar to the technologies used in the past. However, computers have made the whole design and manufacturing process easier. The results are also more precise, and now plastic parts are often the preferred choice for advanced technological and scientific applications. We are one of the Guide bush and welcome to send us messagesz!
• Notice Flow Lines Of Mold Parts

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  Flow lines appear as a wavy pattern often of a slightly different color than the surrounding area and generally on narrower sections of the molded component. They may also appear as ring-shaped bands on a product’s surface near the entry points of the Mold parts, or “gates”, which the molten material flows through. Flow marks won’t typically impact the integrity of the component. But they can be unsightly and may be unacceptable if found in certain consumer products, such as high-end sunglasses. Causes and remedies for flow lines Flow lines are most often the result of variations in the cooling speed of the material as it flows in different directions throughout the mold. Differences in wall thickness can also cause the material to cool at different rates, leaving behind flow lines.injection molding defects For example, molten plastic, cools very quickly during the injection process and flow marks are evident when the injection speed is too slow. The plastic becomes partially solid and gummy while still filling the mold, causing the wave pattern to appear. Here are some common remedies for flow lines in injection-molded products: Increase the injection speed, pressure and material temperature to ensure the material fills the mold before cooling Round the corners of the mold where wall thickness increases to help keep flow rate consistent and prevent flow lines Relocate mold gates to create more distance between them and the mold coolant to help prevent the material from cooling too early during flow Increase the nozzle diameter to raise flow speed and prevent early cooling We are one of the Guide bush and welcome to your come and purchase!
• We Introduce Advantages of Our Mold Parts

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  1. Flexibility of design One of the key reasons behind the invention of plastic injection Mold parts is the ability to be flexible in designs. The flexibility of the technique is one of the most remarkable features that attracts clients in need of plastic parts. The ability to choose multiple plastics (material selection), create precise designs, be flexible in terms of color choices, the process covers it all. This allows the users to create designs of their choice which is a significant change when compared to the traditional molding processes. 2. Precision with complex designs The techniques used within plastic injection molding make it possible to create complex designs and add a large number of details to the parts. Since the injection molds are subjected to high pressure, the plastics get pressed harder which makes it possible to create complex designs. This makes it possible to create intricate design features within plastic parts to a complete precision level which is completely impossible with conventional molding machines. The fabrication of any type of plastic parts can be created to a precision level within 0.001 inches. Additionally, since the process is completely automated, even the most complex of designs are comparatively inexpensive to manufacture. If you are interested in Guide bush, welcome to contact us!
• Common Quality Defects Advised By Plastic Mold Factory

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  Plastic injection molding is a very cost-effective method for mass production of parts – but even the best designs sometimes have shortcomings that result in quality defects. It is important to be familiar with these defects in order to identify and trouble-shoot them, as well as avoid them by developing a competent design! Below are the top 5 most common quality defects in injection molding and how each can be resolved. Additionally, for more information on these and other types of cosmetic defects see the glossary that was compiled by Plastic mold factory. 1. Flash Flash is a thin layer of plastic that flows outside of the cavity, typically where the two halves of the injection mold meet. Flash can appear on the part’s edge along the parting line of the mold. It can also occur at ejector pin locations and anyplace where the mold has metal meeting metal to form the boundary of the part. Flash cools and remains attached to the final product. Injection molders must remove unwanted flash by a process called deflashing which may involve operations personnel or robots trimming the excess material in between cycles. The presence of flash usually results in a longer, more labor-intensive process, lower product quality, and ultimately damage to the mold – all leading to higher costs! For these reasons, the root cause of flash issues needs to be identified and resolved. Below are some causes and remedies for flash. Flash occurs when the mold cavity halves are not held together with enough pressure; thus, one remedy is to increase the clamp force. Flash may occur if the material is too fluid. Consider decreasing the operating temperature to achieve the desired material flow. Flash may be the result of trapped gases inhibiting the material flowing freely; ensure there is adequate gas venting. Flash may be caused by poorly fitting, or designed, mold plates; inspect the mold and make any necessary repairs or replacements. 2. Weld Lines A weld line refers to a line, notch or color change that is created on the molded part caused by the convergence of two separate flows of molten plastic. This occurs wherever there is a hole, notch, or any other feature on a part which divides the flow of plastic into 2 separate “flow fronts.” As these flow fronts come together on the other side of a given feature, the molten plastic rejoins or “welds” together and often forms a slight line on the part, similar to a parting line mark. At the spot where the two flows rejoin there is inadequate interfusing of the plastic – perhaps because there is already partial cooling and then re-solidification of the plastic at this point, or perhaps on a molecular level the molecules are not oriented in the same direction of the flow path. In any case, the result is a weld line and in some cases a reduction in strength. Below are some options that may resolve or move weld lines to a more desirable location for improved aesthetic or strength reasons; however, OEMs should work with their manufacturing partner before implementing these steps to ensure solving a weld line issue does not create a different problem. Increase the temperature of the mold or plastic material in order for the two flow fronts to interfuse better. The gate location influences where the weld line is on the part. Change the gate positions before the mold is fabricated in order to inject the material at more ideal locations and have weld lines in a more preferable location. Changing the product wall thicknesses will result in a different fill time, and may cause the flow fronts to meet at a different spot and move the weld line location. Adjust the design to be a single source flow to avoid the issue caused by two or more flow fronts, or use a raw material with a lower viscosity to improve flow conditions. Increase the injection speed in order to fill the mold more quickly and ensure the material does not prematurely cool down; in addition, when the speed is adjusted the flow fronts may meet at a different spot and move the weld line location. 3. Sink Marks A sink mark is a local depression on the surface of a part. These marks are typically found in thicker areas due to varying cooling rates across the part or insufficient cooling while the part is in the mold. They can also be caused by low pressure in the cavity or an excessive temperature at the gate. To resolve sink marks, the mold temperature can be lowered, the holding pressure raised, or holding time prolonged to encourage more adequate and even cooling. Additionally, adjusting the part design to reduce the thickness of thick wall sections will also promote quicker cooling and reduce the probability of sink marks. If you are interested in Positioning component, welcome to contact us!