Blow Molding Process on Manufacturing Technology .
Tackles about the definition of Blow molding process, its various types , advantages and disadvantages and the application of it on a manufacturing set-up.
Thermoforming is a process where a plastic sheet is heated and formed into a desired shape using pressure, vacuum, or mechanical methods. There are three main thermoforming methods: vacuum forming uses vacuum pressure to draw the heated sheet onto a mold; pressure forming uses compressed air to force the sheet onto the mold more quickly; and mechanical forming uses matching molds to shape the sheet without vacuum or pressure. Common materials thermoformed include plastics like ABS, polyethylene, and PVC. Applications include food packaging, automotive and aircraft parts.
The document provides an overview of injection moulding, including:
- The history of injection moulding beginning in the 1870s.
- The injection moulding process which involves injecting molten plastic into a closed mould.
- The main types of injection moulding machines: hand, plunger, and reciprocating screw types.
- Key machine components like the screw and their functions in plasticizing and injecting the material.
- Common materials used for injection moulding like ABS, nylon, polypropylene.
Blow molding is a manufacturing process that uses air pressure to form hollow plastic parts like bottles. There are three main blow molding processes: extrusion blow molding where a tube of molten plastic (parison) is captured in a mold and inflated, injection blow molding where a preform is first injection molded and then blown, and stretch blow molding where preforms are first made via injection molding and then reheated and blown into shape. Blow molding can make parts from various plastics like PET, HDPE, and PP. It is used widely to make containers and bottles for foods, drinks, chemicals and more.
The document discusses multi-layer composite films and the extrusion process used to produce them. It describes how multiple polymer layers from different extruders can be combined into a single film through a multi-manifold die. The film is then cooled on chill rollers before undergoing slitting, gauging, and winding into rolls. Properties like optical clarity and barrier performance can be optimized through adjustments to materials, temperatures, and processing speeds. Common polymers used include polyolefins like polyethylene and polypropylene.
Extrusion blow molding is a manufacturing process used to make hollow plastic parts like bottles. It begins by melting plastic and extruding it into a tube-like parison. The parison is clamped into a mold and compressed air is injected to push the plastic out against the mold walls. As the plastic cools and hardens, the mold opens and the final part is ejected. Common materials for extrusion blow molding include polyethylene, polypropylene, and PET which must have good melt strength. The process offers low costs due to simple molds but is limited to hollow shapes.
Extrusion is a process that uses pressure to force a billet through a die opening to create an object with a constant cross-section. Most metals are hot extruded due to the large forces required. Extrusion can produce complex shapes, especially for more readily extrudable metals like aluminum. Common extruded products include automotive and construction parts. Factors like temperature, pressure, and lubrication affect the extrusion process and properties of the final product. Defects can occur due to non-uniform deformation or temperatures that cause cracking.
Blow Molding Process on Manufacturing Technology .
Tackles about the definition of Blow molding process, its various types , advantages and disadvantages and the application of it on a manufacturing set-up.
Thermoforming is a process where a plastic sheet is heated and formed into a desired shape using pressure, vacuum, or mechanical methods. There are three main thermoforming methods: vacuum forming uses vacuum pressure to draw the heated sheet onto a mold; pressure forming uses compressed air to force the sheet onto the mold more quickly; and mechanical forming uses matching molds to shape the sheet without vacuum or pressure. Common materials thermoformed include plastics like ABS, polyethylene, and PVC. Applications include food packaging, automotive and aircraft parts.
The document provides an overview of injection moulding, including:
- The history of injection moulding beginning in the 1870s.
- The injection moulding process which involves injecting molten plastic into a closed mould.
- The main types of injection moulding machines: hand, plunger, and reciprocating screw types.
- Key machine components like the screw and their functions in plasticizing and injecting the material.
- Common materials used for injection moulding like ABS, nylon, polypropylene.
Blow molding is a manufacturing process that uses air pressure to form hollow plastic parts like bottles. There are three main blow molding processes: extrusion blow molding where a tube of molten plastic (parison) is captured in a mold and inflated, injection blow molding where a preform is first injection molded and then blown, and stretch blow molding where preforms are first made via injection molding and then reheated and blown into shape. Blow molding can make parts from various plastics like PET, HDPE, and PP. It is used widely to make containers and bottles for foods, drinks, chemicals and more.
The document discusses multi-layer composite films and the extrusion process used to produce them. It describes how multiple polymer layers from different extruders can be combined into a single film through a multi-manifold die. The film is then cooled on chill rollers before undergoing slitting, gauging, and winding into rolls. Properties like optical clarity and barrier performance can be optimized through adjustments to materials, temperatures, and processing speeds. Common polymers used include polyolefins like polyethylene and polypropylene.
Extrusion blow molding is a manufacturing process used to make hollow plastic parts like bottles. It begins by melting plastic and extruding it into a tube-like parison. The parison is clamped into a mold and compressed air is injected to push the plastic out against the mold walls. As the plastic cools and hardens, the mold opens and the final part is ejected. Common materials for extrusion blow molding include polyethylene, polypropylene, and PET which must have good melt strength. The process offers low costs due to simple molds but is limited to hollow shapes.
Extrusion is a process that uses pressure to force a billet through a die opening to create an object with a constant cross-section. Most metals are hot extruded due to the large forces required. Extrusion can produce complex shapes, especially for more readily extrudable metals like aluminum. Common extruded products include automotive and construction parts. Factors like temperature, pressure, and lubrication affect the extrusion process and properties of the final product. Defects can occur due to non-uniform deformation or temperatures that cause cracking.
Extrusion is a high-volume manufacturing process where plastic material is melted and forced through a die to create a continuous profile. There are various types of extrusion processes depending on the final product, such as sheet/film extrusion, tubing extrusion, and wire coating. Extruders use either single or twin screws to melt, mix, and convey the plastic material. The processing section of the extruder subjects the material to different conditions like melting, mixing, venting and homogenization. Wear of extruder components can reduce efficiency over time. Final products are cut into pellets using various pelletizing systems after exiting the die.
Thermoforming is a manufacturing process where sheets of thermoplastic are heated until soft, formed into shapes using molds, and trimmed. There are three main types - vacuum forming uses suction to draw the plastic against molds, pressure forming uses compressed air, and mechanical forming uses movable molds. Common materials are ABS, polyethylene, and PVC. Applications include food packaging, automotive parts, aircraft windows, and more.
Injection molding is a manufacturing process that uses molds to produce plastic or rubber parts. Molds are hollow blocks that give the part its shape and allow it to cool. Thermoplastics can be molded repeatedly while thermosetting plastics set permanently after one molding. Injection molding machines consist of a hopper, barrel with a reciprocating screw, nozzle, and molds. The process involves melting plastic in the heated barrel and injecting it into the mold under pressure before allowing it to cool into the final shape.
This document discusses different types of extrusion dies used in plastic extrusion processes. It classifies dies into five main categories: sheet dies, flat-film and blown-film dies, pipe and tubing dies, profile extrusion dies, and coextrusion dies. For each category, the document provides a brief description and schematic diagrams to illustrate key features. It highlights important design considerations for dies like dealing with non-uniform die swell in profile dies. The benefits of using stack plate dies for better quality and material savings are also noted.
The document discusses various polymer processing techniques. It begins by explaining that the main goal of polymer processing is to produce usable objects and lists the necessary parameters for processing including flow, heat transfer, mass transfer, and chemical reactions. It then focuses on extrusion, describing it as shaping material by forcing it through a die. Various extrusion techniques are discussed including single screw extrusion, twin screw extrusion, blown film extrusion, co-extrusion, and injection molding. Other processing methods summarized include thermoforming, vacuum forming, rotational molding, calendering, and spinning.
The document discusses the polymer extrusion process. It begins by defining extrusion as a process that forces softened polymer through a die to create constant cross-section products like rods, sheets, pipes and films. It then describes the main steps: plastic is fed into a hopper and pushed by a rotating screw through heating zones in a barrel before exiting through a die. Key components are identified as the screw, barrel, die and cooling unit. Extrusion is used mainly for thermoplastics to create continuous, low-cost products like pipes, films and plastic sheets.
Plastics are polymers formed through polymerization reactions that join small organic molecules into long chains. Monomers are the basic building blocks that undergo polymerization to create polymers. There are two main types of polymerization: addition polymerization and condensation polymerization. Addition polymerization involves breaking carbon double bonds in monomers to form chains, producing thermoplastics. Condensation polymerization reacts two different organic molecules to form plastic molecules and byproducts. A variety of additives can be mixed with plastics to modify properties, improve performance, or reduce costs.
Blow Molding is defined appropriately and also the process compatible materials are listed. Blow Molding is broadly classified as - extrusion type, injection type, Multilayer type. All three processes are explained appropriately with diagrams and their application is also listed. Since every thing has advantages and disadvantages, so is the case with blow molding. References are also cited correctly. I hope you all find it useful
Composite materials are composed of two or more physically distinct phases that produce properties different from the individual components. Composites can be very strong yet light weight. Examples include fiberglass, carbon fiber reinforced plastics, and cemented carbides. Composites find applications in aerospace, automotive, sports equipment due to their high strength to weight ratio and other advantageous properties. They are classified based on matrix material (polymer, metal, ceramic) and type of reinforcement (particles, fibers).
(1) Compression molding is a manufacturing process used to mold thermosetting materials under heat and pressure in a mold cavity.
(2) The process involves preheating the molding material, placing it into the mold, applying pressure using a hydraulic press, and allowing the material to cure.
(3) Compression molding is commonly used to make electrical parts, dinnerware, gears, buttons, and automotive and medical components. It allows for high volume, low-cost production with minimal material waste.
Filament winding is a process that creates circular composite products with a hollow core by winding fiber material and resin around a mandrel or core. The fiber is wound in a precise pattern while under tension. The wound part is then cured either at room temperature or in an oven, after which the mandrel is removed, leaving a hollow composite structure. Filament winding is used to create products like storage tanks, pipes, aerospace and vehicle parts, and more.
This document discusses various types of polymer matrix composites, their processing techniques, and applications. It begins by defining polymer matrix composites and describing different types of matrices, including thermoset and thermoplastic polymers. Several processing methods for thermoset composites are then outlined, such as hand layup, filament winding, and resin transfer molding. Common thermoplastic processing techniques like injection molding and film stacking are also mentioned. The document concludes by noting some applications of polymer matrix composites.
The document discusses compounding, which is the process of intimately mixing ingredients into a homogeneous mass. There are various criteria and factors that influence compounding, including selecting the appropriate polymer and ingredients based on requirements. Additives can be incorporated at different stages, and various mixing methods are used depending on the material properties and production needs, including dry mixing, batch mixing, continuous mixing, and screw extrusion. Key compounding methods include single and twin screw extruders, which efficiently mix ingredients using heating elements and intermeshing screw motions.
This document discusses various methods for producing composites, which are divided into open molding and closed molding. Open molding methods described include hand lay-up, spray-up, and filament winding. Closed molding methods include compression molding, pultrusion, vacuum bag molding, and vacuum infusion processing. Each method is briefly described in terms of its process, molds used, advantages, and typical products produced.
1. The document describes different types of moulds used in plastic injection molding including two plate, three plate, split cavity, side core, and hot runner moulds.
2. A split cavity mould is suitable for moulding components with all-round external undercuts and uses sliding splits, angular lifts, or pins for actuation.
3. A side core or side cavity mould is used for components with local external undercuts and can be actuated via finger cams, dog leg cams, cam tracks, springs, or hydraulics.
IRJET- Parametric Study and Development of different Plastics and it’s We...IRJET Journal
This document discusses plastics and their welding techniques. It begins with an introduction to plastics, their properties, and common types of plastics used in engineering like polycarbonate, polypropylene, polybutylene terephthalate, acrylonitrile butadiene styrene, polyethylene, polyimide, and polyvinyl chloride. It then discusses different welding techniques for plastics like adhesive bonding, mechanical fastening, hot plate welding, hot gas welding, ultrasonic welding, and laser welding. Each technique is described and their advantages and limitations are provided in a table. The role of plastic welding in different industries like automotive, aerospace, and construction is also discussed. The document concludes that plastic welding
Extrusion is a high-volume manufacturing process where plastic material is melted and forced through a die to create a continuous profile. There are various types of extrusion processes depending on the final product, such as sheet/film extrusion, tubing extrusion, and wire coating. Extruders use either single or twin screws to melt, mix, and convey the plastic material. The processing section of the extruder subjects the material to different conditions like melting, mixing, venting and homogenization. Wear of extruder components can reduce efficiency over time. Final products are cut into pellets using various pelletizing systems after exiting the die.
Thermoforming is a manufacturing process where sheets of thermoplastic are heated until soft, formed into shapes using molds, and trimmed. There are three main types - vacuum forming uses suction to draw the plastic against molds, pressure forming uses compressed air, and mechanical forming uses movable molds. Common materials are ABS, polyethylene, and PVC. Applications include food packaging, automotive parts, aircraft windows, and more.
Injection molding is a manufacturing process that uses molds to produce plastic or rubber parts. Molds are hollow blocks that give the part its shape and allow it to cool. Thermoplastics can be molded repeatedly while thermosetting plastics set permanently after one molding. Injection molding machines consist of a hopper, barrel with a reciprocating screw, nozzle, and molds. The process involves melting plastic in the heated barrel and injecting it into the mold under pressure before allowing it to cool into the final shape.
This document discusses different types of extrusion dies used in plastic extrusion processes. It classifies dies into five main categories: sheet dies, flat-film and blown-film dies, pipe and tubing dies, profile extrusion dies, and coextrusion dies. For each category, the document provides a brief description and schematic diagrams to illustrate key features. It highlights important design considerations for dies like dealing with non-uniform die swell in profile dies. The benefits of using stack plate dies for better quality and material savings are also noted.
The document discusses various polymer processing techniques. It begins by explaining that the main goal of polymer processing is to produce usable objects and lists the necessary parameters for processing including flow, heat transfer, mass transfer, and chemical reactions. It then focuses on extrusion, describing it as shaping material by forcing it through a die. Various extrusion techniques are discussed including single screw extrusion, twin screw extrusion, blown film extrusion, co-extrusion, and injection molding. Other processing methods summarized include thermoforming, vacuum forming, rotational molding, calendering, and spinning.
The document discusses the polymer extrusion process. It begins by defining extrusion as a process that forces softened polymer through a die to create constant cross-section products like rods, sheets, pipes and films. It then describes the main steps: plastic is fed into a hopper and pushed by a rotating screw through heating zones in a barrel before exiting through a die. Key components are identified as the screw, barrel, die and cooling unit. Extrusion is used mainly for thermoplastics to create continuous, low-cost products like pipes, films and plastic sheets.
Plastics are polymers formed through polymerization reactions that join small organic molecules into long chains. Monomers are the basic building blocks that undergo polymerization to create polymers. There are two main types of polymerization: addition polymerization and condensation polymerization. Addition polymerization involves breaking carbon double bonds in monomers to form chains, producing thermoplastics. Condensation polymerization reacts two different organic molecules to form plastic molecules and byproducts. A variety of additives can be mixed with plastics to modify properties, improve performance, or reduce costs.
Blow Molding is defined appropriately and also the process compatible materials are listed. Blow Molding is broadly classified as - extrusion type, injection type, Multilayer type. All three processes are explained appropriately with diagrams and their application is also listed. Since every thing has advantages and disadvantages, so is the case with blow molding. References are also cited correctly. I hope you all find it useful
Composite materials are composed of two or more physically distinct phases that produce properties different from the individual components. Composites can be very strong yet light weight. Examples include fiberglass, carbon fiber reinforced plastics, and cemented carbides. Composites find applications in aerospace, automotive, sports equipment due to their high strength to weight ratio and other advantageous properties. They are classified based on matrix material (polymer, metal, ceramic) and type of reinforcement (particles, fibers).
(1) Compression molding is a manufacturing process used to mold thermosetting materials under heat and pressure in a mold cavity.
(2) The process involves preheating the molding material, placing it into the mold, applying pressure using a hydraulic press, and allowing the material to cure.
(3) Compression molding is commonly used to make electrical parts, dinnerware, gears, buttons, and automotive and medical components. It allows for high volume, low-cost production with minimal material waste.
Filament winding is a process that creates circular composite products with a hollow core by winding fiber material and resin around a mandrel or core. The fiber is wound in a precise pattern while under tension. The wound part is then cured either at room temperature or in an oven, after which the mandrel is removed, leaving a hollow composite structure. Filament winding is used to create products like storage tanks, pipes, aerospace and vehicle parts, and more.
This document discusses various types of polymer matrix composites, their processing techniques, and applications. It begins by defining polymer matrix composites and describing different types of matrices, including thermoset and thermoplastic polymers. Several processing methods for thermoset composites are then outlined, such as hand layup, filament winding, and resin transfer molding. Common thermoplastic processing techniques like injection molding and film stacking are also mentioned. The document concludes by noting some applications of polymer matrix composites.
The document discusses compounding, which is the process of intimately mixing ingredients into a homogeneous mass. There are various criteria and factors that influence compounding, including selecting the appropriate polymer and ingredients based on requirements. Additives can be incorporated at different stages, and various mixing methods are used depending on the material properties and production needs, including dry mixing, batch mixing, continuous mixing, and screw extrusion. Key compounding methods include single and twin screw extruders, which efficiently mix ingredients using heating elements and intermeshing screw motions.
This document discusses various methods for producing composites, which are divided into open molding and closed molding. Open molding methods described include hand lay-up, spray-up, and filament winding. Closed molding methods include compression molding, pultrusion, vacuum bag molding, and vacuum infusion processing. Each method is briefly described in terms of its process, molds used, advantages, and typical products produced.
1. The document describes different types of moulds used in plastic injection molding including two plate, three plate, split cavity, side core, and hot runner moulds.
2. A split cavity mould is suitable for moulding components with all-round external undercuts and uses sliding splits, angular lifts, or pins for actuation.
3. A side core or side cavity mould is used for components with local external undercuts and can be actuated via finger cams, dog leg cams, cam tracks, springs, or hydraulics.
IRJET- Parametric Study and Development of different Plastics and it’s We...IRJET Journal
This document discusses plastics and their welding techniques. It begins with an introduction to plastics, their properties, and common types of plastics used in engineering like polycarbonate, polypropylene, polybutylene terephthalate, acrylonitrile butadiene styrene, polyethylene, polyimide, and polyvinyl chloride. It then discusses different welding techniques for plastics like adhesive bonding, mechanical fastening, hot plate welding, hot gas welding, ultrasonic welding, and laser welding. Each technique is described and their advantages and limitations are provided in a table. The role of plastic welding in different industries like automotive, aerospace, and construction is also discussed. The document concludes that plastic welding
This document discusses using plastic waste as an alternative fuel source. It begins by outlining the growing problem of plastic waste and its negative impacts on soil quality and the environment when dumped on land or in oceans. The study then examines the calorific (energy) value of different types of recycled plastics, finding their potential energy is comparable to fuels like pet coke and coal. The document goes on to describe a experiment where plastic waste was "co-processed" as an alternative fuel in a cement plant. Results showed using plastic waste along with pet coke as fuel increased the heat required for cement production only slightly. Emissions from the plant were also still within prescribed limits. The study concludes that plastic waste has potential to be
RECYCLING THE WASTE PLASTIC MATERIAL WITH THE HELP OF HEAT TREARTMENTjaideep kishanpuri
The document is a project report submitted for a degree in mechanical engineering. It discusses recycling waste plastic material through heat treatment. The objectives are to study the effect of sulfuric acid treatment on zeolite catalyst characteristics and its use in waste polypropylene pyrolysis. It aims to optimize the process to produce liquid fuel from different plastics and characterize the fuel properties. The report also examines engine performance and emissions from the waste plastic fuel. It scopes thermal and catalytic pyrolysis of plastics like polypropylene, low density polyethylene, and polystyrene to produce liquid fuels using kaolin activated catalyst. The methodology involves pyrolyzing plastic waste at 200-350°C in a reactor to produce similar diesel-like
IRJET- Pyrolysis of Waste Plastic into FuelIRJET Journal
This document summarizes a study on pyrolyzing waste plastic into fuel. The researchers collected various types of waste plastic and pyrolyzed them in a reactor at 500 degrees Celsius. This produced a semi-liquid fuel that was further distilled. Testing found the plastic fuel had properties similar to diesel, including flash point and calorific value. When used in a compression ignition engine, the plastic fuel showed brake thermal efficiencies up to 27.5% and lower emissions than diesel fuel. The study concluded pyrolyzing plastic waste into fuel is an effective way to reduce plastic waste and provide an alternative fuel source.
The document discusses converting plastic waste into fuel through pyrolysis. It begins with an introduction to plastic waste issues and types of plastics. It then discusses plastic waste management techniques like pyrolysis. The document outlines the pyrolysis process, including the apparatus used, process description, and properties of the resulting fuel. It conducted an experiment to pyrolyze plastic waste and analyze the fuel properties and potential engine performance. The aim is to provide a viable solution for plastic recycling by converting it into a usable fuel.
This study evaluated the durability and bonding characteristics of concrete with partial replacement of natural coarse aggregate with recycled plastic aggregate. Specimens were subjected to acid and sulfate attacks to measure durability. Results found the plastic aggregate concrete had lower weight loss and higher compressive strength than control mix after attacks. Bonding tests also found similar bonding stress between mixes. The study concluded plastic aggregate can improve concrete durability and its use supports sustainable construction.
IRJET- Influence of Natural Fiber Powders with Carboxy Methyl Cellulose on Me...IRJET Journal
This document summarizes research on composite plates made from coconut shell powder, palm kernel powder, and carboxymethyl cellulose. Samples of the composite were made with different ratios of the materials and tested for properties including tensile strength, hardness, biodegradability, and water solubility. Testing found that the sample with 30% coconut shell powder, 15% palm kernel powder, and 55% carboxymethyl cellulose (Plate E) had the highest tensile strength and hardness. Plate A was found to be the most biodegradable, decomposing the most in soil and water tests. The composites showed potential for applications depending on their different mechanical and physical properties.
This document summarizes a study on converting plastic waste into fuel through pyrolysis. Plastic production has increased pollution as most plastics are not biodegradable. Pyrolysis, the thermal decomposition of plastics at high temperatures, was used to break down plastic polymers into hydrocarbon fuels like petrol, kerosene and diesel. Low density polyethylene plastic waste was pyrolyzed in a reactor at 300°C. The resulting plastic fuel was filtered, purified and tested. Testing showed the plastic fuel had properties similar to diesel, including color, density, viscosity and calorific value. While plastic fuel production addresses waste and fuels, drawbacks include safety, odor and respiratory issues. The study concludes pyrolysis is an effective way to
IRJET- Pilot Study on Treatment of Plastic by Pyrolysis Process for Productio...IRJET Journal
This document discusses a pilot study on treating plastic waste through pyrolysis to produce oil. Pyrolysis is the thermal decomposition of materials at elevated temperatures in an oxygen-free environment. In this study, low-density polyethylene plastic waste was pyrolyzed in a stainless steel reactor heated to 500°C to produce an oil with properties similar to aviation fuel. The pyrolysis process breaks the long polymer chains in plastics into smaller molecules of oil, gas and char. If optimized, pyrolysis has the potential to reduce plastic waste in landfills and produce a renewable alternative fuel from recycled plastics.
IRJET- Pilot Study on Treatment of Plastic by Pyrolysis Process for Produ...IRJET Journal
1. The document discusses a pilot study on treating plastic waste through pyrolysis to produce oil. Plastic waste like polyethylene was pyrolyzed without a catalyst to produce fuel oil with properties similar to aviation fuel.
2. Pyrolysis is presented as a way to reduce plastic waste pollution while increasing fuel availability. The process converts waste plastic into useful oil through thermal decomposition.
3. Common plastics suitable for pyrolysis include high density polyethylene, which was used in this study. The pyrolysis of plastics typically yields 45-50% oil, 35-40% gases, and 10-20% tar.
Sustainability of the product is becoming a crucial factor for success in the market. Sustainability theory and methods are quite general. This research constitutes a serious attempt to assess the sustainability of plastic sheet piling, and calculate the product carbon footprint. In the case of plastic sheet piling no significant previous research has been done to address sustainability. The product lifecycle including stages such as raw material production, manufacturing, transportation, installation, and disposal/recycling, and its related supply chain have been analysed in detail to identify those factors that have impact on the product carbon footprint and the three main dimensions of sustainability: environmental, social and economic. The installation stage, which is not normally addressed in this kind of studies, has been assessed by the development of a case study.
EXPERIMENTAL CHARACTRIZATION OF HYBRID COMPOSITE MATERIALS FOR TENSION, FLEXU...IRJET Journal
This document describes an experimental study that characterized the mechanical properties of hybrid composite materials made of jute cloth, E-glass fibers, and polyester resin. Specimens were fabricated using hand layup and tested in tension, flexure, and impact. Tensile testing measured Young's modulus, flexural testing measured flexural strength, and Charpy testing measured impact strength. The study found that hybrid composites, which combine natural and synthetic fibers, perform better than composites with a single fiber type due to benefits from both fibers. Characterizing mechanical properties of hybrid composites is important as their use increases in industries like aerospace, military, and automotive.
Ford uses recycled plastic bottles to make vehicle seats. Specifically, Ford grinds down used plastic bottles into pellet form and mixes them with virgin resin to create durable seat material. This allows Ford to reduce waste while incorporating sustainable materials into vehicle production. Using recycled plastic bottles eliminates millions of bottles from landfills each year. The material made from recycled bottles is as durable as traditional seat material but has a higher recycled content.
IRJET- Utilization of Waste Plastic in Flexible PavementsIRJET Journal
This document discusses utilizing waste plastic in flexible pavements. Plastic is a major pollutant when burned and its use can help solve disposal problems. The study involves partially replacing bitumen used in bituminous mixes with shredded waste plastic pieces. This is intended to improve mix properties and pavement life while reducing pollution. The methodology describes preparing control and modified mixes using 0%, 5%, 7%, and 10% plastic replacement. The mixes are tested using the Marshall stability test to evaluate the effects of plastic inclusion. Results will help determine the optimal plastic content for strength and durability gains in bituminous pavements.
The document discusses utilizing plastic waste as an alternative fuel. It describes how plastic waste is produced in large quantities and poses environmental issues. The document then summarizes previous research that has shown plastic oils produced from pyrolyzing plastic waste have properties similar to diesel and gasoline. The paper also outlines the methodology used, including types of plastics studied, production of oil through pyrolysis, and testing of the plastic oil as a fuel in diesel engines. Performance, emissions and fuel properties were found to be comparable to conventional fuels. The document concludes that plastic waste oils can be a viable alternative transportation fuel.
IRJET- Use of Recycled Poly Lactic Acid (PLA) Polymer in 3D Printing: A ReviewIRJET Journal
This document summarizes research on using recycled poly lactic acid (PLA) polymer in 3D printing. It discusses how PLA can be recycled through a closed-loop process to produce 3D printing filament. Studies show that the mechanical and thermal properties of recycled PLA are similar to virgin PLA after one recycling cycle, but deteriorate with additional cycles. The document also examines combining recycled PLA with virgin PLA to improve properties. Adding 25% virgin PLA to recycled PLA maintained tensile strength after double recycling. Coating recycled PLA pellets with polydopamine also increased tensile strength of printed components, providing a potential method to enhance recycled plastics.
A Research onto Study the Properties of Concrete with Partial Replacement of ...ijtsrd
This document summarizes a research study that investigated the properties of concrete with partial replacement of aggregates by plastic aggregates. The study found that replacing sand aggregates with plastic aggregates in concrete leads to a reduction in compressive and tensile strength but increases the thermal insulation properties of concrete. A series of experiments were conducted replacing sand with various proportions of plastic aggregates. The main conclusion was that compressive strength initially increases with small proportions of plastic aggregates but then decreases at higher proportions. The document reviews several other studies that investigated the impact of plastic inclusion on concrete workability and found that slump and density generally decrease with higher plastic content replacement.
Production Fuel From Waste Plastic By Pyrolysis (Theoretical part)Alitek97
In our experiments, commercially available shredded plastics were procured and washed before pyrolysis. Pyrolysis it is one of the most favorable and effective disposing methods, the process is an environmentally friendly and efficient way to eliminate the effect of plastic. Pyrolysis is the thermal degradation of solid wastes at high temperatures (250- 325℃) in the absence of air (and oxygen). The main process given below:
1. Identification of waste plastics. (PE/PP/PS/LDPE/HDPE)
2. Crash and cut the plastic for the pyrolysis process
3. Condensation of the gas to obtain raw fuel.
4. Collect the sample and perform tests to identify the kinds of fuel produced.
The document discusses rolling contact bearings. It begins by defining bearings and their purpose of supporting loads while permitting relative motion. It then discusses the different types of rolling contact bearings, including deep groove ball bearings, angular contact bearings, cylindrical roller bearings, taper roller bearings, and self-aligning bearings. The document also covers bearing materials, static load capacity, and Stribeck's equation for calculating static load capacity.
Operation research unit 3 Transportation problemDr. L K Bhagi
Formulation of Transportation Problem, Initial Feasible Solution
Methods, Degeneracy in Transport Problem and Optimality Test (Modi Method and stepping stone Method)
Operation research unit 2 Duality and methodsDr. L K Bhagi
The document discusses the benefits of meditation for reducing stress and anxiety. Regular meditation practice can calm the mind and body by lowering heart rate and blood pressure. Meditation may also have psychological benefits like improving mood and reducing rumination.
MEC395 Measurement System Analysis (MSA)Dr. L K Bhagi
Discussed SPC, variable Gauge R&R, Repeatability and Reproducibility with Examples calculation of variable Gauge R&R, Bias, Linearity and Stability with examples.
Sheet Metal Working, Temperature and sheet metal forming, Applications Sheet Metal Parts, Categories of sheet metal processes, Shearing, stages in shearing action, Punch and Die Sizes, Sheet Metal Bending
Eco-industrial park and cleaner productionDr. L K Bhagi
1. Industrial ecology is the study of material and energy flows through industrial systems.
2. It takes a multidisciplinary approach and examines issues from perspectives involving the environment, society, economics, and technology to promote sustainable development.
3. The goal is to shift industrial processes from linear open loop systems that produce waste, to closed loop systems where wastes can be used as inputs for new processes.
The document contains a series of questions and answers related to gears and gear design. It discusses topics like tooth interference, torque transmission ratios, speed reductions, minimum number of teeth, center distance calculations, and stress analysis. For each question, the relevant concepts and equations are explained to arrive at the solution. Gear terminology and relationships between different gear types and shaft arrangements are also covered.
The document discusses helical gears. Some key points:
- Helical gears have teeth cut at an angle (helix angle) ranging usually between 15-30 degrees, compared to spur gears which have straight teeth parallel to the shaft axis.
- Helical gears can be parallel, crossed, or herringbone. Herringbone gears cancel thrust loads by using two sets of teeth with opposite hands.
- Helical gears carry more load than equivalent spur gears because the teeth act over a larger effective area due to the helix angle. However, efficiency is lower for helical gears due to increased sliding contact.
- Additional geometry considerations are required for helical gears, including normal and transverse pit
Introduction to casting, Major classifications of casting, Casting terminology, Characteristics of molding sand, Constituents of foundry sand, Patterns and their types, Cores and types of cores, Gating system, Types of gates, Solidification, Riser system, Types of riser, Types of allowances, Directional Solidification, Defects in casting, Riser design(Chvorinov's rules), Advanced casting techniques:Shell molding, Permanent mould casting, Vacuum die casting, Low pressure die casting, Continuous casting, Squeeze casting, Slush casting, Vacuum casting, Die Casting, Centrifugal casting, Investment casting
Introduction to casting, Major classifications of casting, Casting terminology, Characteristics of molding sand, Constituents of foundry sand, Patterns and their types, Cores and types of cores, Gating system, Types of gates, Solidification, Riser system, Types of riser, Types of allowances, Directional Solidification, Defects in casting, Riser design(Chvorinov's rules), Advanced casting techniques:Shell molding, Permanent mould casting, Vacuum die casting, Low pressure die casting, Continuous casting, Squeeze casting, Slush casting, Vacuum casting, Die Casting, Centrifugal casting, Investment casting
Design of Flat belt, V belt and chain drivesDr. L K Bhagi
Geometrical relationships, Analysis of belt tensions, Condition for maximum power transmission, Characteristics of belt drives, Selection of flat belt, V- belt, Selection of V belt, Roller chains, Geometrical relationship, Polygonal effect, Power rating of roller chains, Design of chain drive, Introduction to belt drives and belt construction, Introduction to chain drives
Springs - DESIGN OF MACHINE ELEMENTS-IIDr. L K Bhagi
Introduction to springs, Types and terminology of springs, Stress and deflection equations, Series and parallel connection, Design of helical springs, Design against fluctuating load, Concentric springs, Helical torsion springs, Spiral springs, Multi-leaf springs, Optimum design of helical spring
General introduction to manufacturing processesDr. L K Bhagi
Manufacturing processes definition, Classification of manufacturing processes, Typical examples of applications, Manufacturing capability, Selection of materials, Selection of manufacturing process
This document is a series of lecture slides about sheet metal working and bending processes. It discusses topics like mechanics of sheet metal bending, bend allowance, numerical problems calculating blank size and bending force, springback and methods to eliminate it, including overbending and stretch forming. It also covers drawing as a sheet metal forming operation used to make cup-shaped or complex curved parts by pushing metal into a die cavity with a punch.
Press tool operations, Shearing action, Shear operations, Numerical problems, Drawing, Draw die design, Spinning, Bending, Stretch forming, Embossing and coining, Types of sheet metal dies, Analysis of sheet metal
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
TIME DIVISION MULTIPLEXING TECHNIQUE FOR COMMUNICATION SYSTEMHODECEDSIET
Time Division Multiplexing (TDM) is a method of transmitting multiple signals over a single communication channel by dividing the signal into many segments, each having a very short duration of time. These time slots are then allocated to different data streams, allowing multiple signals to share the same transmission medium efficiently. TDM is widely used in telecommunications and data communication systems.
### How TDM Works
1. **Time Slots Allocation**: The core principle of TDM is to assign distinct time slots to each signal. During each time slot, the respective signal is transmitted, and then the process repeats cyclically. For example, if there are four signals to be transmitted, the TDM cycle will divide time into four slots, each assigned to one signal.
2. **Synchronization**: Synchronization is crucial in TDM systems to ensure that the signals are correctly aligned with their respective time slots. Both the transmitter and receiver must be synchronized to avoid any overlap or loss of data. This synchronization is typically maintained by a clock signal that ensures time slots are accurately aligned.
3. **Frame Structure**: TDM data is organized into frames, where each frame consists of a set of time slots. Each frame is repeated at regular intervals, ensuring continuous transmission of data streams. The frame structure helps in managing the data streams and maintaining the synchronization between the transmitter and receiver.
4. **Multiplexer and Demultiplexer**: At the transmitting end, a multiplexer combines multiple input signals into a single composite signal by assigning each signal to a specific time slot. At the receiving end, a demultiplexer separates the composite signal back into individual signals based on their respective time slots.
### Types of TDM
1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
IEEE Aerospace and Electronic Systems Society as a Graduate Student Member
Plastic processing
1. Unit-5
Plastic processing
Dr. L.K. Bhagi
Associate Professor
School of Mechanical Engineering
Lovely Professional University
“Polymer Processing” may be defined as the
manufacturing activity of converting raw
polymeric materials into finished products of
desirable shape, microstructure and
properties.
3. This material is man made and is a by product of the oil industry.
PLASTICS
4. Plastic» Difference between Polymer and
Plastic
Polymer
The word POLYMER means ‘many’ ‘mers’
✓ A ‘mer’ is a unit
✓ Polyethylene means many ‘ethylenes’
✓ The molecular weight of a polymer (length of the chain
– number of ‘mers’) will effect the properties.
• 10-20 ethylenes – greases or oils
• 200-300 waxes
• 20,000 + polyethylene
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adhesives, lubricants, paints, films, fibers,
plastic goods, etc.
5. Plastic» Difference between Polymer and
Plastic
Plastic
The word plastic derives from the Greek plastikos meaning
"capable of being shaped or molded”.
Plastics are polymers, but all polymers are not plastics.
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6. Plastic» Applications
Construction
The Construction sector is the second highest user of plastics
after packaging.
They have great versatility and combine excellent strength
to weight ratio, durability, cost effectiveness, low maintenance
and corrosion resistance which make plastics an
economically attractive choice throughout the construction
sector.
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7. Plastic» Applications
Electrical and Electronic
Wherever we find electricity, we also find plastics. In the
kitchen, there are the labour-saving devices that we
wouldn’t be without; Refrigerator, washing machines,
microwave ovens, kettles.
In the living room is the television, or the music system,
while at work, we may use a computer, telephone. Plastics
make progress possible, making electrical goods safer,
lighter, more attractive, and more durable.05-11-2019
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8. Plastic» Applications
Packaging
Plastic packaging allows us to protect, preserve, store and
transport products in a variety of ways.
Without plastic packaging, a great deal of products that
consumers purchase would not make the journey to
the home or store, or survive in good condition long
enough to be consumed or used.
Durability, Safety, Hygiene, Light Weight and Design Freedom
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9. Plastic» Applications
Transport
All forms of transport require energy to run and fuel
represents a substantial part of running costs. Cutting the
weight of cars, aeroplanes, boats and trains can cut fuel
consumption dramatically. The lightness of plastics
therefore makes them invaluable to the transport industry.
105kg of plastics, rather than metals, in a car weighing
1,000kg makes possible a fuel saving of up to 7.5%.
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10. Plastic» Advantages
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Advantages of plastics include:
1. Corrosion resistance and resistivity to chemicals,
2. Low electrical & Thermal conductivity,
3. Low density,
4. High strength to weight ratio, particularly when reinforced,
5. Noise reduction,
6. Wide choices of colors and transparencies,
7. Ease of manufacturing and complexity of design possibilities,
8. Relatively low cost.
11. Dr. L.K. Bhagi
Associate Professor
School of Mechanical Engineering
Lovely Professional University
12. Plastic» Plastic Processing
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There are many processes for plastics. Selection of a process
depends on many factors including:
- Quantity and production rate
- Dimensional accuracy and surface finish
- Form and detail of the product
- Nature of material
- Size of final product
In general, plastics processes have three phases:
1. Heating - To soften or melt the plastic
2. Shaping / Forming - Under constraint of some kind
3. Cooling - So that it retains its shape
21. Plastic»
Resins
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Natural resins: Natural resins are
obtained from the viscous substances
secreted from the bark of trees and the
stems of other plants.
it is soluble in alcohol and related
compounds, but not in water. Once
dry, the resin will not admit water
intrusion.
Collecting
Resin from
pine trees
into a bag
22. Plastic»
Resins
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Synthetic resins:
is artificial synthesized high molecular polymer. Therefore,
different types of plastic can be called after the name of the
synthetic resin it is made from.
Synthetic resin is organic
compound made by combining
carbon atom, hydrogen atom, and
a small quantity of oxygen atom,
sulphur atom through certain
chemical bond.
23. Plastic»
Resins
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Synthetic resins:
Synthetic resin, the basic raw material of plastic, takes up
30%~60% or more of its composition. It has the function of not
only binding itself together, but also the other materials firmly
together.
As the type, property, and amount of synthetic resin change,
the physical and mechanical properties of plastic also
change. Therefore, the main properties of plastic depend on
the synthetic resin it is made from.
24. Plastic»
Polymerization
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The Chemical process by which monomers are combined to
form polymers is known as polymerization.
The following two methods are used to achieve polymerization
1. Addition polymerization
2. Condensation polymerization
26. Plastic»
Polymerization
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In addition polymerization, two or more similar
monomers directly react to form polymers.
Addition polymerization involves the linking of
monomers with double bonds. The double bond
of one monomer breaks and links onto the
neighboring monomer. This process continues to
form polymers, some of which can be many
thousands of monomers long.
27. Plastic»
Polymerization
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Condensation polymerization (that yield the
condensate) takes two or more dissimilar monomers
both have hydrogen (H) and hydroxyl groups (OH)
attached to them. When they come together with an
appropriate catalyst one monomer loses H while the
other loses OH group and combine to form water (H2O),
and the remaining electrons form a covalent chemical
bond between the monomers. This reaction occurs over
and over again until you get a long chain of copolymers
29. Plastic»
Additives in plastics
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Additives use:
– To improved or modify the mechanical, chemical, and
physical properties
– To prevent degradation (both during fabrication and in
service)
– To reduce materials costs
– To improve the process-ability
Typical additives include
• Filler materials,
• Plasticizer
• Stabilizers,
• Colorants,
• Flame retardants
30. Plastic»
Additives in plastics »Filler Material
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➢ Filler materials are most often added to polymers to improve
tensile and compression strengths, Hardness, toughness,
dimensional and thermal stability and other properties.
➢ Materials used as particulate fillers include wood flour, silica
flour, glass, clay, talc, limestone (CaCO3), and even some
synthetic polymers.
➢ Because these inexpensive materials replace some volume of
the more expensive polymer, the cost of the final product is
reduced.
31. Plastic»
Additives in plastics »Plasticizers
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Plasticizers are chemicals added to a polymer to make it
softer and more flexible, and to improve its flow
characteristics during forming.
The commonly used plasticizers are Phthalates (Most widely
use as plasticizer) camphore, paraffins, napathalanes,
phosphates etc.
Example depending on the proportion of plasticizer in the
mix, PVC can be obtained in a range of properties, from rigid
and brittle to flexible and rubbery.
32. Plastic»
Additives in plastics »Stabilizers
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➢ Polymer absorbs heat, light energy and causes crazing,
cracking, color changes, or loss of mechanical properties
➢ PVC has poor thermal properties and has used a large amount
of stabilizers, mostly cadmium based.
➢ Lead and cadmium stabilizers have been replaced with barium-
zinc, calcium-zinc, magnesium-zinc formulations.
33. Plastic»
Additives in plastics »Flame Retardants
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Nearly all polymers burn if the required heat and oxygen are
supplied. Some polymers are more combustible than others.
Flame retardants are chemicals added to polymers to reduce
flammability by following mechanisms:
(1) Interfering with flame propagation, (2) Producing large
amounts of incombustible gases, and/or (3) Increasing the
combustion temperature of the material. The chemicals may also
function to (4) Reduce the emission of toxic gases generated
during combustion.
34. Plastic»
Additives in plastics »Colorants
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An advantage of many polymers over metals or ceramics is that
the material itself can be obtained in most any color. This
eliminates the need for secondary coating operations.
Colorants for polymers are of two types:
pigments and dies
Pigments are finely powdered materials that are insoluble in and
must be uniformly distributed throughout the polymer in very low
concentrations, usually less than1%. They often add opacity as
well as color to the plastic. Dies are chemicals, usually supplied
in liquid form, that are generally soluble in the polymer.
35. Plastic»
Classification of Polymers
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Classification of Polymers
Based on Source
Natural polymers
(Proteins, cellulose, starch,
some resins and rubber)
Semi-synthetic
polymers
Synthetic polymers
plastic (polythene), synthetic
Fibers (nylon 6,6) and synthetic
rubbers
Based on Structure
Linear polymers
High density polythene, PVC etc.
Branched chain
Polymers
Low density polythene
Cross linked
Bakelite,
melamine etc.
Mode of
polymerisation
Molecular
Forces
Addition
polymers
Condensation
Polymers
Elastomers
Fibers
Thermo
plastic
retract to its
original
position after being
stretched
high tensile
strength and high
modulus.
Thermo
setting
36. Plastic»
Types of Plastics
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• Plastics are mainly classifieds into two types:
depending on how they are structurally and chemically
bonded
1. Thermoplastic Plastics:
2. Thermosetting Plastics
37. Plastic»
Types of Plastics » Thermo plastics
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• These plastics can be softened by heating and hardened
by cooling any number of times without changing the
properties of the material.
• It is thus possible to shape and reshape these plastics by
means of heat and pressure.
• One important advantage of this variety of plastics is that
scrap obtained from old and wornout articles can be
effectively used again.
38. Plastic»
Types of Plastics » Thermo plastics
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The notable Properties of thermoplastic materials are:
1. They are light in weight.
2. High Strength and toughness
3. Better hardness
4. Good resistance to most of the chemical
5. They have good corrosive resistance.
6. Durability
7. They are cheap compared to metals.
8. Painting and polishing is not necessary.
39. Plastic»
Types of Plastics » Thermo plastics
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1. Polyvinyl chloride ( P V C )
Properties : Rigid , tough , elastic to feel.
Uses : Plumbing pipes and sanitary fittings are manufactured out
of this material. Shower curtains , window frames, flooring ,
corrugated roofing sheets , plastic coating to steel sheets tanks,
water cisterns, etc.
2. Acrylic:
Properties: Glass clear , some what brittle sound
when tapped.
Uses : Glazing , bath rooms and sinks.
THERMO PLASTIC MATERIALS
40. Plastic»
Types of Plastics » Thermo plastics
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THERMO PLASTIC MATERIALS
3. Polyethylene ( or polythene ) – low density:
Properties: Flexible, feels like paraffin wax.
Uses ; bottles, buckets, packaging rolls.
4. Polyethylene ( or polythene )- high density:
Properties: stiff and hard, coarser than the
polythylene of low density
used as large storage bottles, water tank.
5. Polypropylene:
Properties : smooth, rigid, lightest of all
plastics – it floats in water.
Uses : cisterns, sink traps, washing machine,
food containers, appliances , car fender.
41. Plastic»
Types of Plastics » Thermo plastics
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THERMO PLASTIC MATERIALS
6. Polystyrene: Solid state at room temperature, but flows if
heated above its glass transition temperature and becoming
solid again when cooling off.
Pure solid polystryrene is a colourless, hard plastic with
limited flexibility. Polysterene can be transparent
or can be made to take on various colours.
Uses : Refrigerator containers, food trays,
packaging, food containers, disposable cups,
plates, cutlery, CD boxes.
42. Plastic»
Types of Plastics » Thermo plastics
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THERMO PLASTIC MATERIALS
7. Nylon:
Properties : High density polythene but smoother to feel.
Uses: Textiles, brush bristles, carpeting, surgical trays,
bearings, pressure tubing.
43. Plastic»
Types of Plastics » Thermosetting plastics
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These plastics are either originally soft or liquid or they soften
once upon heating, they harden permanently.
When they are heated in the temperature of 127-177°C, they set
permanently and further application of heat does not alter their
form or soften them.
But at temperature of about 343°C, the charring (become blackened
as a result of partial burning) occurs. The thermosetting plastics are
durable, strong and hard.
They are available in a variety of colours. They are mainly used in
engineering applications of plastics.
44. Plastic»
Types of Plastics » Thermosetting plastics
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Properties :
1. Permanently hard on heating above a certain temperature.
2. Undergoes chemical changes during manufacture.
3. Cannot be melted and reshaped.
4. Little potential for recycling.
45. Plastic»
Types of Plastics » Thermosetting plastics
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Examples and uses:
1. Polyurethanes: insulating foams, mattresses, coatings,
adhesives, car parts, print rollers, shoe soles, flooring,
synthetic fibers, etc. Polyurethane polymers are formed
by combining two bi- or higher functional monomers.
2. Bakelite, a phenol-formaldehyde resin used in electrical
insulators and plastic ware
3. Urea-formaldehyde foam used in plywood, particleboard
and medium-density fiberboard
4. Melamine resin used on worktop surfaces.
5. Epoxy resin used as the matrix component in many fiber
reinforced plastics such as glass-reinforced plastic and
graphite-reinforced plastic)
46. Plastic»
Types of Plastics » Thermosetting plastics
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1. Melamine formaldehyde:
Properties : Hardest of common plastics , heat resistant.
2. Phenolics ( Bakelite ) :
Properties : The cheapest. heavy solid plastic material, fishy smell
when burnt dark in color, heat resistant.
Uses : Bottle caps, plastic automobile parts,
bonding plywood and chip board, glues,
laminates with other materials.
47. Plastic»
Types of Plastics » Thermosetting plastics
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3. Urea formaldehyde :
PROPERTIES : Similar to phenolic but can be produced in lighter
colours.
Uses : Door furniture, light switches, and electrical fittings, glues,
bottoms, radio cabinets, etc.
4. Epoxies:
Properties: Resin and hardener.
Uses: Used as adhesives.
5. Polyesters :
Properties: produced as fibres and films.
Uses : Used for reinforced plastics.
48. Plastic» Difference Between Thermoplastic
and Thermosetting plastic
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49. Plastic» Difference Between Thermoplastic
and Thermosetting plastic
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Thermoplastic
Thermosetting
52. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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A process in which material is forced to flow through a die
orifice to provide long continuous product whose
cross - sectional shape is determined by the shape of the
orifice/die
• Widely used for thermoplastics and elastomers to mass
produce items such as tubing, pipes, hose, structural
shapes, sheet and film, continuous filaments, and coated
electrical wire
• Carried out as a continuous process; extrudate is then cut
into desired lengths
53. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Components and features of a (single screw) plastic extruder
54. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Extruder Barrel
• Internal diameter typically ranges from 25 to 150 mm
• L/D ratios usually between 10 and 30
• Feedstock fed by gravity onto screw whose rotation moves
material through barrel
• Electric heaters melt feedstock; subsequent mixing and
mechanical working adds heat which maintains the melt
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Extrusion of Plastics
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Two Main Components of an Extruder
1. Barrel
2. Screw
• Die - not an extruder component
– Special tool that must be fabricated for particular profile to
be produced
56. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Extruder Screw
Feed section: feedstock is
moved from hopper and
preheated
Compression section: polymer
is transformed into fluid, air
mixed with pellets is extracted
from melt, and material is
compressed
Metering section: sufficient
pressure developed to pump it
through die opening.
Divided into sections to serve several functions:
The feeding capacity of the
screw is determined by its
geometry and speed of rotation.
57. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Breaker Plate
• Progress of polymer melt through barrel leads ultimately to the die
zone
• Before reaching die, the melt passes through a screen pack - series
of wire meshes supported by a breaker plate containing small
holes
58. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Breaker Plate
Functions of screen pack and breaker plate:
– Filter out contaminants and hard lumps
– Build pressure in metering section
– Improves the mixing of the plastic before entering the die
59. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Die Configurations and Extruded Products
• The shape of the die orifice determines the cross-sectional
shape of the extrudate.
• Common die profiles and corresponding extruded shapes:
– Solid profiles
– Hollow profiles, such as tubes
– Wire and cable coating
– Sheet and film
– Filaments
60. Plastic» Plastic Processing Technologies»
Extrusion of Plastics
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Extrusion Advantages
• Equipment is simple and relatively inexpensive.
• Short lead time Since it uses simple dies which can be very
quickly produced.
• Relatively low tooling costs
• Overall cost of the parts produced by extrusion is low
• Practically any cross-section can be easily produced
62. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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production of color master for
plastic injection molding parts
Extruder Operation and Control
63. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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• Injection molding is the most widely used molding process for
thermoplastics.
64. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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Injection molding is a process in which a polymer is heated to a
highly plastic state and forced to flow under high pressure into a
mold cavity, where it solidifies.
The molded part, called a
molding, is then removed from the
cavity. The process produces
discrete components that are
almost always net shape.
65. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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The mold determines the part shape
and size and is the special tooling in
injection molding.
For large, complex parts, the mold can
cost hundreds of thousands of dollars.
For small parts, the mold can be built to
contain multiple cavities, also making
the mold expensive.
Thus, injection molding is economical
only for large production quantities.
66. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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An injection molding machine consists of two principal
components: (1) the plastic injection unit and (2) the mold
clamping unit.
67. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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The injection unit is much like an extruder.
68. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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The injection unit is much like
an extruder.
It consists of a barrel that is fed from
one end by a hopper containing a
supply of plastic pellets.
Inside the barrel is a screw, in addition to turning for mixing and heating the
polymer, it also acts as a ram that rapidly moves forward to inject molten plastic
into the mold.
69. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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A non-return valve mounted near
the tip of the screw prevents the
melt from flowing backward along
the screw threads.
Later in the molding cycle the ram
retracts to its former position.
Because of its dual action, it is
called reciprocating screw, a
name that also identifies the
machine type.
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INJECTION MOLDING
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The clamping unit is concerned with the operation of the mold.
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INJECTION MOLDING
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The clamping unit is concerned with the operation of the mold. Its
functions are to
(1) Hold the two halves of the mold in proper alignment with each
other;
(2) Keep the mold closed during injection by applying a clamping
force sufficient to resist the injection force; and
(3) Open and close the mold at the appropriate times in the molding
cycle. The clamping unit consists of two platens, a fixed platen and
a moveable platen, and a mechanism for translating the latter.
72. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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Step1- The uncured rubber or plastic is fed into the machine in the form
of a continuous strip, powder or granules.
Step 2 - The uncured rubber is worked and warmed by an auger screw in
a temperature controlled barrel.
Step 3 - As the rubber stock accumulates in the front of the screw, the
machine is ready to make a shot.
Step 4 - With the mold held closed under hydraulic pressure, the screw is
pushed forward. This forces the rubber into the mold, similar to
the action of a syringe.
Step 5 - While the rubber cures in the heated mold, the screw turns again
to refill.
Step 6 - The mold opens and the part can be removed. The machine is
ready to make the next shot, as soon as the mold closes.
73. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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Common defects in injection molded:
Short shots. As in casting, a short shot is a molding that has
solidified before completely filling the cavity. The defect can
be corrected by increasing temperature and/or pressure. The
defect may also result from use of a machine with insufficient
shot capacity, in which case a larger machine is needed.
74. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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Common defects in injection molded:
Flashing
Flash, also called “burrs”, is an excess of molding material that
appears as a thin lip or protrusion at the edge of a component.
Flashing occurs when the polymer melt is squeezed into the
parting surface between mold plates; it can also occur around
ejection pins.
75. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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Common defects in injection molded:
Sink marks. These are defects usually related to thick molded
sections. A sink mark occurs when the outer surface on the
molding solidifies, but contraction of the internal material
causes the skin to be depressed below its intended profile.
76. Plastic» Plastic Processing Technologies»
INJECTION MOLDING
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Advantageous
• Fast production.
• Low labour costs.
• High-output production.
• Multiple materials can be used at the same time.
• Can be used to produce very small parts.
Limitations
• High initial tooling and machinery cost.
• Small number of parts can be costly.
78. Plastic» Plastic Processing Technologies»
COMPRESSION MOLDING
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Compression molding process consists of two steps, preheating
and pressurizing.
Compression molding is generally used for thermosetting plastic.
79. Plastic» Plastic Processing Technologies»
COMPRESSION MOLDING
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Process Description
80. Plastic» Plastic Processing Technologies»
COMPRESSION MOLDING
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Step 1- A piece of uncured rubber is placed in the mold.
Step 2 - The mold is closed up and held under hydraulic pressure
while the rubber cures due to temperature.
Step 3 - When the mold opens the part can be removed. The
excess rubber, called flash, needs to be trimmed off the part.
The process employs thermosetting resins in a partially cured
stage, either in the form of granules, putty-like masses, or
preforms.
Compression molding is a high-volume, high-pressure method
suitable for molding complex, high-strength fiberglass
reinforcements.
81. Plastic» Plastic Processing Technologies»
COMPRESSION MOLDING
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Advantages
• Lowest cost
• More uniform density
• Uniform shrinkage due to uniform flow
• Improved impact strength due to no degradation of
fibers during flow
• Dimensional accuracy
• Residual stresses are minimized
82. Plastic» Plastic Processing Technologies»
COMPRESSION MOLDING
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Materials used in this process
A. Thermosetting polymers
B. Thermoplastic:
• Ultra High Molecular Weight Polyethylene (UHMWPE)
• Long fiber reinforced thermoplastics
83. Plastic» Plastic Processing Technologies»
COMPRESSION MOLDING
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Advantages
• Large curing time
• scrap cannot be reprocessed.
Applications & products
• Dinnerware
• Buttons
• Electrical Appliance Housings
• Radio Cases
85. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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• In the transfer molding, polymer charge is transferred
from the transfer pot to the mold. The mold is cooled and
molded part is ejected.
• Generally, thermoset plastics (such as epoxy, polyester,
phenol-formaldehyde, vinyl ester, silicone) are processed
by transfer molding process, but certain thermoplastic
materials can also be processed.
• This process is widely used to encapsulate items such as
integrated circuits, plugs, connectors, pins, coils etc.
86. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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• The required amount of polymer charge is weighted and
inserted into the transfer pot.
2. The transfer pot is heated by the heating element above
the melting temperature of the polymer charge.
3. The plunger is used to push the liquid polymer charge
from the transfer pot into the mold cavity.
4. The mold cavity is held closed until the resin gets cured.
The mold cavity is opened and the molded part can be
removed.
87. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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• This is similar to compression molding and injection
molding
• But the different from compression molding in that the
mold is enclosed rather than open to the fill plunger
• In injection molding we use heat to melt the material and
then press to make the casting. But in transfer molding we
use only pressure to make the casting.
88. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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89. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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Step 1 - A piece of uncured rubber is placed into a portion of the mold
called the “pot”.
Step 2 - The mold is closed up and under hydraulic pressure the
rubber is forced through the small hole into the final cavity.
The mold is held closed while the rubber cures.
Step 4 - Mold is opened and the part can be removed. The flash and
the gate may need to be trimmed.
90. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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Pros:
▪ Fast setup time and lower setup costs
▪ Low maintenance cost
▪ Plastic parts with metal inserts can be made
▪ Design flexibility
▪ Dimensionally stable
Cons:
▪ Wastage of material
▪ Production rate lower than injection molding
▪ Air can be trapped in the mold
91. Plastic» Plastic Processing Technologies»
TRANSFER MOLDING
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Applications
• Natural gas industry
• Electrical industry
• Hydraulic industry
• Wind turbine blades
• Medical composites
• Aerospace and automobile parts
• Bathroom fixtures, car body, helmets, etc…
93. Plastic» Plastic Processing Technologies»
BLOW MOLDING
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Molding process in which air pressure is used to inflate soft
plastic into a mold cavity
• Important for making one-piece hollow plastic parts with
thin walls, such as bottles
• Because these items are used for consumer beverages in
mass markets, production is typically organized for very
high quantities
94. Plastic» Plastic Processing Technologies»
BLOW MOLDING
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Accomplished in following steps:
1. Plasticizing(make plastic ) or melting the resin
2. Fabrication of a starting tube, called a parison
(The parison is a tube-like piece of plastic with a hole
in one end).
3. Inflation of the tube to desired final shape
4. Ejection of the part
5. Trimming and finishing of the part
95. Plastic» Plastic Processing Technologies»
BLOW MOLDING
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96. Plastic» Plastic Processing Technologies»
BLOW MOLDING
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Forming the parison is accomplished by either
Blow molding process
Extrusion blow
molding
Injection blow molding
97. Plastic» Plastic Processing Technologies»
BLOW MOLDING
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Extrusion Blow Molding
(1) Extrusion of parison (2) Parison is pinched at the top and sealed at
the bottom (3) the tube is inflated so that it takes the shape of the
mold cavity; and (4) mold is opened to remove the solidified part.
98. Plastic» Plastic Processing Technologies»
BLOW MOLDING
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Injection Blow Molding
(1) Parison is injection molded around a blowing rod (2) injection mold
is opened and parison is transferred to a blow mold; (3) soft polymer is
inflated to conform to the blow mold; and (4) blow mold is opened and
blown product is removed.
99. Plastic» Plastic Processing Technologies»
BLOW MOLDING
05-11-2019
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Some typical APPLICATIONS are
➢ HDPE : High Density Polyethylene (stiff bottle, toys, cases,
drum)
➢ LDPE : Low Density Polyethylene (flexible bottle)
➢ PP : Polypropylene (higher temperature based bottles)
➢ PVC : Polyvinyl Chloride (oil resistant containers)
➢ PET : Polyethylene terephthalate (Water Bottles)
100. Plastic»
Plastic Processing Technologies
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1. Extrusion
2. Injection molding
3. Compression molding
4. Transfer molding
5. Blow molding
6. Thermoforming (Disposable Cup Thermoforming Machine)
101. Plastic» Plastic Processing Technologies»
THERMOFORMING
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In its basic operation, a flat thermoplastic sheet of specific size is
clamped in place, heated to its softening temperature, then forced
against the contours of a mold or form by either air or vacuum
pressure or by mechanical means.
Once cooled, the thermoformed part retains the shape of the mold
or form.
Materials: PVC, PE, HIPS, ABS and PC.
102. Plastic» Plastic Processing Technologies»
THERMOFORMING
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103. Plastic» Plastic Processing Technologies»
THERMOFORMING
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104. Plastic» Plastic Processing Technologies»
THERMOFORMING » Vacuum Thermoforming
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Advantage:
• Operated comparatively low vacuum pressure.
• Relatively cheap.
Disadvantage:
• Uneven wall thickness at the corner of the product.
• Bad finishing or non uniform plastic concentration.
• Therefore the thinnest area occur at the corner, near
the clamp
Plastic» Plastic Processing Technologies»
THERMOFORMING » Vacuum Thermoforming
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• Alternative to vacuum forming.
• Here, the air pressure is forced to the preheated sheet
into cold mold. The air pressure is much higher than the
vacuum forming.
• The basic difference between vacuum forming is the
heated sheet is pressured from above the mold cavity.
• Due to high pressure, the heated sheet can be deformed
in fraction of a second.
(High production rate)
Plastic» Plastic Processing Technologies»
THERMOFORMING » Pressure Thermoforming
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Plastic» Plastic Processing Technologies»
THERMOFORMING»Mechanical Thermoforming
• Here, positive and negative molds are brought against
heated plastic sheet, forcing it to the assumed shape.
• Air between the die and sheet is evacuated by using
vacuum pump, and sheet conforms to the mold shape.
• Formed part is cooled and ejected.
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Plastic» Plastic Processing Technologies»
THERMOFORMING»Mechanical Thermoforming
Advantages:
• Better dimensional control.
• Opportunity for surface detailing of both sides of the
parts.
Disadvantages:
• Two mold halves are required
• Relatively costly.
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Plastic» Plastic Processing Technologies»
THERMOFORMING»Mechanical Thermoforming
Applications:
Thermoforming has many applications like
▪ Food packaging
▪ Automotive parts
▪ Aircraft windscreens
▪ Vehicle doors etc.
115. Plastic» Plastic Processing Technologies»
THERMOFORMING
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116. Plastic» Product Design Guidelines
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• Strength and stiffness
– Plastics are not as strong or stiff as metals
– Avoid applications where high stresses will be encountered
– Creep resistance is also a limitation
Creep resistance can be defined as a material's ability to resist
any kind of distortion when under a load over an extended
period of time
– Strength-to-weight ratios for some plastics are competitive
with metals in certain applications
117. Plastic» Product Design Guidelines
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• Impact Resistance
– Capacity of plastics to absorb impact is generally good;
plastics compare favorably with most metals because in
case of metals brilltle-ness may be present.
• Service temperatures
– Limited relative to metals and ceramics
• Thermal expansion
– Dimensional changes due to temperature changes much
more significant than for metals
118. Plastic» Product Design Guidelines
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• Many plastics are subject to degradation from
sunlight and other forms of radiation
• Plastics are soluble in many common solvents
• Plastics are resistant to conventional corrosion
mechanisms that afflict many metals.
• Metals degrade because of corrosion
119. Plastic» Product Design Guidelines
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• Wall thickness
– Uniform wall thickness is desirable in an extruded cross
section
– Variations in wall thickness results in non-uniform plastic
flow and uneven cooling which tend to warp extrudate
Extrusion
120. Plastic» Product Design Guidelines
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Extrusion
• Hollow sections
– Hollow sections complicate die design and plastic flow
– Desirable to use extruded cross-sections that are not hollow
yet satisfy functional requirements
121. Plastic» Product Design Guidelines
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Extrusion
• Corners
– Sharp corners, inside and outside, should be avoided in
extruded cross sections
– They result in uneven flow during processing and stress
concentrations in the final product
122. Product Design Guidelines: Moulding
• Economic production quantities
– Each part requires a unique mold, and the mold for any
molding process can be costly, particularly for injection
molding
– Minimum production quantities for injection molding are
usually around 10,000 pieces
– For compression molding, minimum quantities are 1000
parts, due to simpler mold designs
– Transfer molding lies between injection molding and
compression molding
123. Product Design Guidelines: Moulding
• Part complexity
– An advantage of plastic molding is that it allows multiple
functional features to be combined into one part
– Although more complex part geometries mean more costly
molds,
– It may nevertheless be economical to design a complex
molding if the alternative involves many individual
components that must be assembled
124. • Wall thickness
– Thick cross sections are wasteful of material, more likely to
cause warping due to shrinkage, and take longer to harden
• Reinforcing ribs
– Achieves increased stiffness without excessive wall
thickness
– Ribs should be made thinner than the walls they reinforce
to minimize sink marks on outside wall
Product Design Guidelines: Moulding
125. Product Design Guidelines: Moulding
• Corner radii and fillets
– Sharp corners, both external and internal, are undesirable in
molded parts
– They interrupt smooth flow of the melt, tend to create
surface defects, and cause stress concentrations in the part
• Holes
– Holes are quite feasible in plastic moldings, but they
complicate mold design and part removal
126. Product Design Guidelines: Moulding
• Draft
– A molded part should be designed with a draft on its sides
to facilitate removal from mold
– Especially important on inside wall of a cup-shaped part
because plastic contracts against positive mold shape
– Recommended draft:
• For thermosets, ~ 1/2 to 1
• For thermoplastics, ~ 1/8 to 1/2
127. • Tolerances
– Although shrinkage is predictable under closely controlled
conditions, generous tolerances are desirable for injection
moldings because of
• Variations in process parameters that affect shrinkage
• Diversity of part geometries
Product Design Guidelines: Moulding