In heated to forming temperature where it

In this assignment i will be describing the deformation process that is used to manufacture a polymer based component.  There are three types of deformation process that are used to make polymer component which are calendering, extrusion and vacuum thermoforming. Calendaring is a process that includes smoothing and compressing materials during the production which is completed by passing the material between heated rolls to reduce the thickness of the material.Vacuum thermoforming is also known as vacuum forming which is a very simple process to shape thermoplastic. The sheet of plastics is heated to forming temperature where it is stretched on a mould and kept on the mould by applying vacuum between the surface. Extrusion is a compression process where the material is forced to flow through a die orifice which is needed to produce long continuous product. This process, mainly use  thermoplastics and elastomers to produce mass products. There are 7 steps in the extrusion process which makes it a relatively fast process. The first step of the process begins with placing the raw resin into the extruder hopper. The second step involves the resin to be fed through the feed throat of the hopper down to the extruder barrel which is caused by gravity.  The third step is the archimedes screw is rotated within the barrel which moves the resin towards the dye. The fourth step of process is where the risen is moved along the barrel due to this the temperature increases to where the resin starts to melt. The temperature depends on the types of thermoplastics used which could be varied between 400 and 550 degrees fahrenheit. The fifth step of the process is the molten plastics is fed into the die cavity from the end of the barrel which is left as the final product is a long continuous shape. This long continuous shape is known as a profile. The sixth step of the process is that the profile extruded from the cooling tank which is filled with water to cool and solidify the plastic. The seventh step of the process is that the profile is cut to the length that is desired.The extrusion of solids profile  normally varies but regular products shapes are round and square. But there are some irregular cross section for example: Structural shapeDoor and windowsAutomobile trims House sidingDuring this process there are some hollow profiles such as tubes, pipes and hoses. These hollow profiles use mandrel to form the shapes. Mandrel held in place using a spider for example the polymer is melts and flows around the legs supporting the mandrel to reunite into a tube wall. Mandrel has air channels which are used for hardening as air is blown inside the tube which maintain the hollow forP6: Composite material is known as composite which are engineered material that are made from two or more types of material with different properties. Composite is two inherently different materials that are combined together to produce a material with properties that exceeds the constituent material.Reinforcement phrase (fibres)Binder Phrase ( compliant matrix)Reinforcement fibres consists of glass, boron, carbon, ceramics and organic material to advance the existing material.There are natural composite such as wood and bamboo. Bamboo is very efficient as its is a very strong composite structure. The properties of structural composites depends on constituent and geometricals design. Composite materials offers high strength, lightweight and design flexibility to the product which makes it more durable.  There are many types of composite moulding processes such as: Hand lay upSpray upVacuum Bag mouldingPressure Bag moulding Compression moulding Hand lay up is  known as the oldest moulding method to composite fabrication processes. This methods is low volume which suggest that the process is very slow and the method needs intensive labour to make the product. Hand lay up is suited especially for larger component such as boats hulls or bath tubs.  Glass or other reinforcing mat is positioned in the open mould manually and resin poured and sprayed over into the glass plies. Entrapped air is removed manually with squeegees to complete the laminate structure. Matrix resin are commonly used by room temperature curing polyesters and epoxies. In the resin system, curing is started by the catalyst which hardens the fibre composite without external heat. To improve the quality of the product, a pigment gel coat is applied to the mould surface. Vacuum Bag moulding is similar to hand lay up as it is uses a vacuum to eliminate entrapped air and excess resin. Pre cut plies of glass are fabricated onto the mould. After a non adhering film of polyvinyl is placed over the lay up to seal the mould flange. From the bag a vacuum is drawn to formed by the film while the composite is set to room temperature. However vacuum bag moulding is different to hand lay up as the vacuum methods provides higher reinforcement concentrations and it has better adhesion betweens layers.

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