Plastic product design machining

Leading the processing growth was the expansion of twin-sheet and pressure-formed plastic products. Fueled mostly by advances in mold technology, material developments, and thermoforming machinery capabilities, technology improvements in the form of machine controls have led to machine designs that are faster and more consistent than was previously possible. As an example advanced materials and... 

As a measure of the level of sophistication of the industry the types of polymers consumed was as shown in figure 2. Others are mainly engineering thermoplastics (ETP), such as nylon, polyacrylates, polyacetals, polycarbonates, polyesters, and polpropylene oxide etc... These ETP s are growing at rates up to 20%. The main uses for plastic products are computer and business machine parts as well as design engineered products. The consumption of styrenic plastics (polystyrene acrylonitrile butadiene styrene - ABS) is high, relative to polyolefins, because of their demand in electric/electronic end-uses. 

A successful plastic product depends on the optimization of each of the following four principal components part design, material selection and handhng, tool design and construction, and processing/machine capabilities. 

The creation of a plastic part requires a series of conscious decisions regarding type of plastic, method of production, design of mold or tooling, and selection of machine or process. Reaching these decisions requires information as to the intended usage of the part and the conditions of environment (temperature, moisture, exposure to harsh atmospheres, physical and electrical requirements). Furthermore, in most cases, the cost to manufacture the part is a major consideration and is dependent on the choice of materials, the manufacturing process, and, of course, the quantities to be produced per shift, month, or year. 

Under this heading of manipulation is included any process whereby the solid plastics material, usually in powder or nib form, is converted to the finished end product. It embraces moulding by compression, transfer, injection or extrusion, blow moulding, rotational moulding, and any process whereby a layer of comminuted plastics material is heat-sintered into a finished unit. In all of them the product designer has to work very closely with the manufacturer not only of the plastics material, but also with the mould maker and to an ever-increasing extent with the maker of the moulding machine. 

In order to understand potential problems and solutions of design, it is helpful to consider the relationships of machine capabilities, plastics processing variables, and product performance (Fig. 1-10). A distinction has to be made here between machine conditions and processing variables. For example, machine conditions include the operating temperature and pressure, mold and die temperature, machine output rate, and so on. Processing variables are more specific, such as the melt condition in the mold or die, the flow rate vs. temperature, and so on (Chapter 8). 

Husky is a global supplier of injection molding systems to the plastics industry. Husky designs and manufactures injection molding machines—from 60 to 8000 tonnes, robots, hot runners for a variety of applications, molds for PET preforms, and complete preform molding systems. Customers use Husky s equipment to manufacture a wide range of products in the packaging, automotive and technical industries. The company serves customers in over 100 countries from more than 40 service and sales offices around the world. 

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