Moulding Techniques for a Brake Caliper - Assignment Example

Primary Process P1: The metallic component is a Brake Caliper Moulding techniques for a Brake Caliper There are several molding techniques applicable for various metal-based component part of a vehicle in this assignment we consider lost foam casting method to mould brake calipers. The moulding techniques applicable in metallic components moulding Powder Injection Moulding (PIM) It enables the cost-effective chains of production of long-lasting, precision metal (MIM) or ceramic (CIM) components. The major advantage of the multistage procedure: freedom of shape, which entails MIM and CIM. Metal injection molding (MIM) This is a metalworking procedure where smoothly-powdered metal is mixed with a calculated amount of binder substance to comprise of a 'feedstock' able to handle by plastic procedures equipment through a method known as injection mold forming. The moulding technique allows multifaceted parts to be shaped in a solitary operation and in high quantity. End products are normally component products applicable in various industries and applications. Below are samples of brake calipers of various make of vehicles. Brake Calipers for Jaguar Brake Caliper (BMW 3) Braker Caliper (Audi A6/100) Brake Caliper (Mitsubishi L / Mitsubish Pajelo) Brake Caliper for Audi A3 Brake Caliper (Peugeot 307) Lost Foam Casting (LFC) It is also known as expandable pattern casting (EPC). LFC involves the substitution of a low solidity foam prototype by liquid metal. It offers the capability of a direct production of nearly any multifaceted geometry including sophisticated cavities and undercuts without tapers and the requirement for considerable completed work (Bhattacharjee 201). Compared to the conservative sand casting methods it has and environment and economical advantages. The actual LFC-system applies patterns of expandable polystyrene (EPS) for manufacturing applications. These patterns, directly designed to shape, are engrossed in a moulding case with binder less sand. The fluid metal, which is dispensed into the molds of the downsprues, vaporizes the EPS model, which is specifically substituted by the metal (Bhattacharjee 201). With the opportunity of assembled prototypes very sophisticated shapes can be generated and the castings can be replicated with amazing dimensional accuracy. Pattern making & cluster assembly Pattern making: The first material needed for pattern production is EPS. First step in the LFC-procedure is the pre-enlargement of EPS beads. After maturing the beads are gusted into a mould producing the pattern part. The mould is then heated up with steam to expand the beads more and tightly fit the hole of the mould. Hot vapor and enlargement of the beads makes them to weld together (Bhattacharjee 201). Cluster assembly. Complicated parts involving hidden cavities and undercuts cannot be moulded in one operational step, but are accumulated from pattern sections into a complete pattern. Amalgamation techniques used are heated platen welding, gluing and plugging. In order to augment the effectiveness of the total process numerous patterns are joined into a cluster and provided with a common gate structure, also made of EPS. The diagram below gives the illustration of the pattern making and cluster assembly. Pattern moulding unit Pattern assembly unit Coating & embedding Coating: The clusters are encrusted with a refractory covering layer by immersion in water soluble terracotta slurry. The coating film has the purpose of guiding the gasification procedure of the prototype and to form a barricade between the moulding substance and the gas-filled effervesce which exists between the still hard EPS-pattern and the obtrusive aluminum melt. After the covering has dried, slim, hard and permeable covering remains (Bhattacharjee 201). The coatings are normally applied to a foam cluster by immersing, spraying or pouring. Embedding in sand; subsequent to coating, cluster is put in a flask and stored with unmixed quartz with no chemical additives. The sand is compressed through vibration with a variety of frequencies, which makes the sand to fill all concealed cavities of the patterns (Dahata 114). Below is the illustration giving the process of coating and embedding. Production steps Coating process Pouring and finishing This entails the process of moulding the components with different patterns. Pouring: During the filling procedure the liquid metal flows via the gate structure into the EPS-prototypes, which is gasified, sealing the cavity and substituting exactly the pattern shape. During this phase it is significant to avoid turbulences, sustain the casting cavity partition and to realize a gradual elimination of the foam outline. The gas oozing from EPS decomposition infused the coating cover and escapes into the sand, supported by an exterior vacuum as illustrated above (Bhattacharjee 201). Specifically, the subsequent sets of constraints have to be adjusted to each other: elective external vacuum, permeability of coating, EPS-pattern solidity and type of glue, metal temperature, Shape of the gating / riser organization and of the patterns. Dumping, quenching and trimming: Following solidification of the process, the sand can be emptied from the flask and be geared up for the subsequent moulding (Dahata 114). Clusters are cooled and removed from the gate system. Below diagrams give the process illustration. Production steps Advantages and disadvantages Advantages: freedom of shape, possibility to generate complicated geometries by accumulation of several EPS parts, no burrs, less cleaning of castings, no draft angles necessary, decrease of amount of machining, binder-less reticulated sand, reduced ecological burden, possible for Rapid Prototyping, Dimensional correctness and less finishing work. long life of moulding tools for EPS patterns High productivity and flexibility. Disadvantages: sand fill and compaction could lead to deformation of pattern, Large number of procedure parameters required to be controlled for best form filling. Health and safety According to health and safety regulation by COSHH, PUWAR and RIDDOH, employees and staffs must be protected from hazardous substances in their place of work. Safety and superiority are among the requirements placed on contemporary materials applied in the automotive industry. Continuous development in the products and parts are the affirmed objectives of all car producers and an acceptable desire of end users. These require unremitting control during the generation of parts and automotive components, commencing with the raw substance right through to the end produce. The close partnership between qualified, autonomous testing laboratories and automotive constituent suppliers guarantee that the car producers' requirements in terms of the first sample testing and sequential sample testing are satisfied. Methods of Reducing risk in Lost Foam casting technique. In order to augment the efficiency of the total procedure several patterns are accumulated into a cluster and supplied with a general gate procedure, also made of EPS. Risk management assessment is a constituent of procurement policy that ensures every product is risk manageable and users’ safety is adhered to. The process minimizes human involvement in the process that reducing the risk incidents. P2: The ceramic component is a spark plug Spark plug Moulding Technique Ceramic Injection Molding The CIM procedure route is the same to MIM. It involves mixing the preferred ceramic powder with binders to shape the feedstock, which is subsequently molded in a die hollow space to form the requisite component shape (Händle 103). These forms undergo a debinding procedure where binders are detached by using either thermal steaming or solvent washing. The components are then accumulated in a sintering kiln at temperatures not exceeding 1800 ˚C, under either reducing atmospheres or oxidizing. The Advantages: It is most advantageous when conservative machining technologies are too costly or unable to perform. It is perfect for components that have a multifaceted shape and where high amount and consistent quality are vital. Applying sub-micron ceramic concentrate, CIM-produced artifacts have a high surface finish and incredibly fine grain components close to hypothetical densities. The Applications: The uses of CIM procedure are virtually unlimited. As ceramic contains high flexural power, hardness and compound inertness, it produces products that are very wear resistant, corrosion resistant and are durable (Händle 103). Ceramic products are applied in electronic assemblage, optical, tools, and others. High-pressure injection moulding The moulding method most suitable for spark plug moulding would be high-pressure injection moulding. During this procedure of moulding, the forming of the ceramic products is done by a high-pressure reciprocating screw injection tool. Ceramic powder and additives are used to mould the figural material into desired shape (Lefebvre 15). Injection moulding facilitates the production of complicated geometries without compromise. Technology: Injection moulding is an industrialized process for generating components from both thermoplastic and thermosetting synthetic materials. Substance is fed into a frenzied barrel, mixed, and enforced into a mold hollow space where it quenches and hardens to the arrangement of the cavity. Advantage: This technology is advantageous, especially injection in ecological protection and energy saving, since use high accuracy injection managed servo motor, velocity is steadier, and still can multistage control (Lefebvre 15). But all the over-bed applying life than in the machine, hydraulic kind; hydraulic injection shaping confidential make sure accuracy of closed-loop power must be used. The servo control device with servo valves, and costly, bring costs rise. The process characteristically separated into inoculation molding machine, injection controlling rubber, plastic, pressure-maintaining, quenching, open prototype and so on numerous stages, each stage needs different pressure and surge. Injection Moulding Process Material granules are liquidize down and added into the mold. The cast is held beneath pressure until the substance cools and hardens (Händle 103). Once solidify, the cast is opened and the component is removed. And the procedure can be recurring. Application: Injection moulding is applied in manufacturing metal, plastic and rubber. Materials are filled through a heated container in the apparatus and enforced into a mold where it will chill and take its form. An injection molding appliance can stamp out metallic car shell components, rubber regulator vapor seals, and even artificial toys for children. Injection casts can stamp out tiny to big items (Lefebvre 15). It can stamp out vehicle components from spark plugs and base pans to ball bearings. Health and safety issue Health and safety is regulated by the government agencies such as COSHH or PUWAR to ensure the working environments are free or has minimized health hazards. Safety during mould changing: Accidents often occur during setting due to parts of the interlocking controlling arrangements have been superseded. A written safe program of work should be offered for setters in regard to the following. Before mould changing The injection part should be withdrawn from the cast and put at a holding temperature, appropriate for the substance held within it, with the needle shut-off control device (if fixed) left open. The energy source to the core-pulling device and ejector pairings should be secluded before contact to them is attempted. ● Suitable lifting apparatus should be obtainable for mould exclusion and substitution. Method of reducing risk during moulding There are safety checks procedures which are in place to mitigate accident risks while working. Procurement of the machines policies are clear to ensure only good quality machines are purchased Training for staff on safety and conduct during the moulding process reduces risk cases. Risk management assessment is a requirement by the regulators of the industries. P3: The polymer component is fan blades Automotive fans comprised of diverse parts. These components involve the fan motor, fan strap, fan grasp, and fan shrouds. Depending on the fan make, the car fan blade figure varies. Below is a sample of fan blade applied in this study. Injection Moulding Injection moulding is the procedure of injecting molten thermoplastic polymer into a hollow space, in a toughened steel mould instrument, which opens on a divide line; following speedy cooling to disclose an artificial moulding (Kamal 9). Typically this procedure is used to create artificial mouldings where the comparatively high tooling cost can be justified by low component costs and leniencies, which cannot be obtained by other moulding processes. Aki specialize in the manufacturing of demanding consumer products which may need any combination of: artistic external finish, close tolerances and engineering polymers colored to a comply specification. Many of the mould apparatus run in moulding machines have multifaceted cores which function in plane ninety degrees to the instrument opening plane (Kamal 9). This enables moulding to incorporate under-cuts and other sophisticated features in their production thereby eliminating or simplify derived assembly operations. Automated de-moulding from the robots is applied extensively to control the consistency of the moulding series. Manual exclusion of mouldings from the cast may differ the cycle and, thus, introduce a changeable which may influence the quality. Technology: Injection moulding is an industrialized process for generating components from both thermoplastic and thermosetting synthetic materials. Substance is fed into a frenzied barrel, mixed, and enforced into a mold hollow space where it quenches and hardens to the arrangement of the cavity. Advantage: This technology is advantageous, especially injection in ecological protection and energy saving, since use high accuracy injection managed servo motor, velocity is steadier, and still can multistage control (Kamal 9). But all the over-bed applying life than in the machine, hydraulic kind; hydraulic injection shaping confidential make sure accuracy of closed-loop power must be used. The servo control device with servo valves, and costly, bring costs rise. Health and safety issue Health and safety is regulated by the government agencies such as COSHH or PUWAR to ensure the working environments are free or has minimized health hazards. Safety during mould changing: Accidents often occur during setting due to parts of the interlocking controlling arrangements have been superseded. A written safe program of work should be offered for setters in regard to the following. Before mould changing: The injection part should be withdrawn from the cast and put at a holding temperature, appropriate for the substance held within it, with the needle shut-off control device (if fixed) left open. The energy source to the core-pulling device and ejector pairings should be secluded before contact to them is attempted. Suitable lifting apparatus should be obtainable for mould exclusion and substitution. Method of reducing risk during moulding: There are safety checks procedures which are in place to mitigate accident risks while working. Procurement of the machines policies are clear to ensure only good quality machines are purchased. Training for staff on safety and conduct during the moulding process reduces risk cases. Risk management assessment is a requirement by the regulators of the industries. Compare and contrast Different Moulding techniques Metal Casting methods Method Process Pros/cons Green sand moulding Huge air cylinders, hydraulics, and inventive explosive methods have enhanced the sand compaction about the pattern, enhancing the standards of correctness and finish which can be accomplished with certain types of castings. Pros: No limit on size and ferrous and non ferrous metals can be used and adaptable. Cons: Low design complexity and accurateness No-Bake Molding Chemical binders such as urethane or furan are blended with sand and put in mold boxes surrounding the pattern halves. Pro: High strength mould, improved dimension repeatability Cons: Patterns maintenance hard Resin Shell Molding Probably the oldest, most computerized and most rapid of the cast (and core making) procedure was the heat-curing method known as the shell method. Pros: Rapid production rate and good dimension casting Cos: energy cost high Expandable Pattern Casting (Lost Foam) The EPC procedure involves attaching extensible polystyrene forms to a stretchy polystyrene gating process and applying an intractable coating to the whole assembly. Pros: no cores needed, reduction in cost, very neat produce Cons: time consuming Vacuum ("V") Process Molding This incorporation of vacuum forming allows molds to be produced out of free-flowing, dry, unbounded sand lacking using jolting, high-pressure squeezing, slinging or gusting as a means of compaction. Pros: all sizes and shapes possible, superb finish and unlimited intricacy. Cons: limitation on the size of casting Recommendations Improvement in moulding processes The most promising section regards mold pressurization - it is well recognized that using a small amount of pressure within to cast at the accurate point in the heating stage of the cycle rapids up the coalescence of the polymer elements during the melting stage, producing a fraction with less foams in a shorter time of time than at atmospheric pressure. This force also delays the division of the part from the cast wall due to reduction during the cooling stage, aiding exclusion of heat from the component and therefore quickening the cooling stage too. The main downside to this is the hazard of explosion of pressurized components to the machinist- something that has prohibited mold pressurization technology adoption. However, with improved heath and safety regulation and automation procedure this would be the improvement needed in moulding technology. Improved health and safety To improve safety of the operator the system would require a great extent of automating processes to reduce the human involvement in the process. This will reduce the risk of an accident occurring due to human errors. Strict measures on health and safety regulations implementation and non-compliances dealt with severely. Work Cited Bhattacharjee, Debashish. Proceedings of the International Symposium on Emerging Challenges for Metals and Materials: Engineering and Technology: November 15, 2009, Kolkata. New Delhi: Allied Publishers Pvt. Ltd, 2011. Print. Dahata, Nilesh. Fillability, Microstructure and Mechanical Properties in Lost Foam Casting of B206 Aluminum-Copper Alloy. Ottawa: Library and Archives Canada = Bibliothèque et Archives Canada, 2009. Print. Händle, Frank. Extrusion in Ceramics. Berlin: Springer, 2007. Print. Kamal, Musa R, and Jean-François Agassant. Injection Molding: Technology and Fundamentals. Munich: Hanser, 2009. Print. Lefebvre, Louis P, John Banhart, David C. Dunand, and L P. Lefebvre. Metfoam 2007: Porous Metals and Metallic Foams: Proceedings of the Fifth International Conference on Porous Metals and Metallic Foams, September 5-7, 2007, Montreal Canada. Lancaster, Pa: DEStech Publications Inc, 2008. Print. Read More