INTRODUCTION Plastic Injection moulding is a manufacturing technology for producing identical parts from a mould. It is the one of the most commercially significant plastic processing method of all as it allows highly automated production with high precision. The process involves the melting of plastic pellets and injecting it at high pressure into cooled steel mould to form desirable shape. Insert moulding is a variant based on this process, in which plastic is moulded over a component with different properties, forming a product with unique visual or ergonomic appeal in one single manufacturing procedure. The process is not limited to two material components, repeated injection process can be performed until the desirable properties have been achieved with the required number of layers. HISTORY Plastic industry has a relatively short history compared to other materials, the industry did not emerge until the 1930s and did not take off until the World War II (Elias, 2003). Manufacturing of plastic parts with heat-meltable plastic was made available followed by the invention of injection moulding machine in the 1930s (Harper, 2006). The origin of this invention can be traced back in the 1872, when the Hyatt brothers invented the ‘packing machine’ that moulds camphor-plasticised cellulose nitrate. The machine was later improved which led to the the version that are commonly used today. The growing importance of added value manufacturing has urge the demand of multi-material moulding in a low-cost and efficient manner. As a consequence, many variants have been developed based on this modern industrial process despite of its young history, as shown in Fig.1. FIg.1 Variations of multi-material injection moulding process In... ... middle of paper ... ...response to specific material feeds through the use of moving slides or inserts, as shown in Fig. 2. The main advantage of this method is the ability to complete the process without having to open the mould or transfer the pre-form to another location for sequential shots of injection. Also, it provides stronger bond between materials as the time between the injection of the two materials can be optimised accordingly, despite the cooling rate might affect the cycle time. However, depend on the number of component in the structure, tooling cost could be relative expensive as high level of intricacy is required to activate all slides and openings. Throughout analysis on the economical implication should be made when considering. Fig.2 Moving slide/insert opens and closes for injection in core back moulding (source: Goodship, 2002) ROTATING TOOL INJECTION
3D printing is primarily for rapid part prototyping and small-run production in a variety of industries. In the meantime, the term additive manufacturing has come to represent the use of 3D printing to create metallic components and final parts, differentiating from conventional subtractive manufacturing processes. 3D printing uses computer-generated designs to create build paths that reproduce a digital model through consolidation of materials with an energy source. The process typically uses a laser, a binder or an electron beam that solidifies material as it is directed along scanned over a pre-placed layer or the build path of material. This method has been used successfully with metals, polymers and ceramics. Metals are still in their infancy in terms of finished part production. Metallic parts produced with 3D printing frequently require additio...
Riordan Manufacturing Inc. is in the field of plastic injection molding. A leader in plastics designs in many different areas, with state of the art capabilities in developing innovative products for their customers. The company was founded by Dr. Riordan, a professor of chemistry, working with processing polymers into high strength plastic articles. Dr. Riordan obtained patents and licensing to start manufacturing plastic fans in the plant at Pontiac, Michigan in 1992. This summary will cover Riordan’s mission, the four plant description, and the companies finance and accounting.
Die-forming of sheet metal has been around for thousands of years. Originally the metal was manipulated by hand and hammered into the depression, by utilizing crude grooves carved into wood or stone. This technique was used to make spouts, handles, and other forms. Since then, however; they have undergone a remarkable technological evolution. Mate-female conforming dies to create hollow forms by using hydraulic pressure or drop hammer pressure, changed die-forming forever (Paisin, 2013).
Some of the issues presented above resulted from inefficiencies in the two distinct processes taking place in the same production facility at Custom Molds, namely the Molds Fabrication process and the Parts Production process (Exhibit 1a and b). The two processes serve different customer needs. Mold fabrication, a skill oriented and craftsman-driven process, requires flexibility and quality. Parts manufacturing, on the other hand, involves a more standardized process that competes on delivery and low cost. The margin for parts is also much smaller.
In additive manufacturing, parts are produced by slicing a CAD model into thin layers and then depositing material one layer at a time to create the 3D part. While current methods are very precise and have high resolutions, I have identified 3 main limitations of additive manufacturing.
CAD – One factor that is often overlooked when introducing this type of process into the manufacturing industry is having personnel trained in the appropriate operational software, such as CAD. When a 2D CAD image is created of the desired design what needs to be kept in mind is that this will also involve calculating bend allowances, inclusion of half etch detail and scaling. To allow for the etching process an etching compensating factor has to be taken into account. This includes drawing the outside profile larger than the finished component size this means holes and slots should be smaller to compensate. The amount of adjustment is directly proportional to the thickness of the metal being processed.
The plastic obtained from polyethylene can be pressed into varying shapes, ranging from the simplest to the most complicated. The ethylene market is indirectly driven by the increased polyethylene consumption for the production of several plastic components. In 2011, the global propylene market is valued at more than $ 90 billion and significant growth is anticipated in the coming years. Acrylic fibers and coatings, PVC plasticizers and coatings, polyurethane resins, epoxy resins and propylene polymers are applied on polycarbonates and solvents, that are used in the production of propylene. The automotive industry is the biggest end-user of polypropylene. The enormous expansion of ethylene and propylene production will contribute to the growth of the ethylene and propylene market, along with the rising demand for downstream products from India, China, and the Middle East. Tight environmental regulations, fluctuations in raw material prices and political uncertainties in crude oil producing regions are the main factors limiting the ethylene and propylene market [9].
Prefabrication -Haas et al (2000), prefabrication normally involves a single skill or trade, such as electrical, or piping, and this can be defined as “a manufacturing process, which generally takes place at a specialized facility, in which various materials are joined to form a component part of a final installation” (Tatum et al., 1987). Components manufactured off-site and is not a complete system can be referred to as prefabricated components. Furthermore Jaillon & Poon (2009) proceed to describe prefabrication as, a manufacturing process, commonly conducted at a specific facility, in which numerous materials are combined to form a component which is part of a final installation. The manufacturing process may be undertaken in different environments such as, a factory environment (factory prefabrication) or (site-prefabrication) on site under the open sky. The term off-site fabrication is utilized when prefabrication and pre-assembly is integrated (Jaillon & Poon, 2009). Gibb (1999) defines off-site prefabrication as a process which integrates prefabrication and pre-assembly. This process includes the design and the manufacture of units or modules, typically away from the work site, and their installation. “Off-site fabrication requires a project strategy that will change the orientation of the project process from construction to manufacture and installation”, (Gibb, 1999). (Klerk, 2013)
Denture teeth can be made of acrylic poly(methyl methacrylate) (PMMA) or composite resins. PMMA is a polymer - a material made the from joining of methyl methacrylate monomers. Properties of PMMA include resistance to abrasion, chemical stability and a high boiling point. (Jun Shen et al. 2011). However, weak flexure and impact strength of PMMA are of concern as they account for denture failure. (Bolayir G, Boztug A and Soygun K. 2013). Composite denture teeth are made of a three distinct phases - filler, matrix and coupling agents. Out of the types of composite teeth available, nano-filled composite teeth are preferred. Composite teeth have a PMMA coating around the tooth and a high content of filler particles. This gives them strength, higher resistance to forces than acrylic teeth and provides compete polymerization due to the PMMA coating. (Anusavice, K. J., Phillips, R. W., Shen, C., & Rawls, H. R, 2012). If the interface between the PMMA denture base and PMMA or composite teeth was weak, the denture will not be able to sustain occlusal forces, making the base-teeth interface, an entity of significance.
On September 7th and 14th of 2000 my lab partners and I conducted the polystyrene bead molding project. My lab partners are Josh Dick, Mike Ward, and Keith Matlock, and we conducted the procedure in room W126 of the Kansas Technology Center. We were to attempt to make polystyrene bead molds using two different methods. In theory we would be able to perform the bead molding.
This is in different with fusing and brazing (which involves melting a lower-melting-point material between the work pieces to form a bond between them) it works without melting the work pieces.
The cost for such a system may be an expensive capital investment, however it is more cost efficient and in the long run costs are kept to the least possible. This is because of resin savings (resin consumption is lowered due to no cold runner), energy savings (due to plasticising, cooling and regrinding in cold runner mould), labour savings (due to no re-grinding and trimming), mould cost saving (since it runs faster than a cold runner system, a smaller mould may be used to produce the same amount of production) and injection press costs (due to the runner being already hot and thus no heat will be lost).
One of the foremost necessary applications of 3D printing is within the medical trade. With 3D printing, surgeons will turn out mockups of components of their patient's body that has to be operated upon. 3D printing makes it doable to form a locality from scratch in mere hours. It permits designers and developers to travel from flat screen to precise half. Today nearly everything from part parts to toys is obtaining engineered with the assistance of 3D printers. 3D printing is additionally used for jewelry and art, design, fashion style, art, design and interior style.
The manufacturing process of steel container or drum which is also known as liquid carrying container involves many processes. Although, there are different sizes of steel containers and different manufacturing process in most steel container manufacturing industries lately. There are also thousands of different steel alloy used in the production of steel containers. Furthermore, steel containers are made of sheet metal by soldering, brazing, spot welding, and seam welding. In addition to this, The Process of making steel containers involves rolling of metal sheet; welding the seam, making 90 degree bent on top and bottom of the container, making number of beads (according to size) and lastly reduce the diameter of one side of the container; fitting of lid to the containers, testing like pressure; coating internal (epoxy phenolic coating or plain) and external (stoving enamel gloss of various colour).
that make thousands of types of plastics. Ink pens, car parts and plastic bags are all made