SAGAR INSTITUTE OF RESEARCH AND TECHNOLOGY INDORE (M.P.) Department of Mechanical Engineering Dissertation Report on THERMAL ANALYSIS OF CONFORMAL COOLING CHANNEL IN PLASTIC MOLDING MACHINE USING MULTI CAVITY MOLD Submitted to RAJIV GANDHI PRODYOGIKI VISHWAVIDYALAYA,BHOPAL (M.P.) Submitted by PRABHAT PATIDAR 0830ME16ME10 SIRT, INDORE Under the Guidance of Mr. Kamlesh Gangrade Assistant Professor Department of Mechanical Engineering SIRT, INDORE ABSTRACT The arrangement of appropriate and satisfactory cooling arrangements is one of the most significant aspects of mould cooling in injection moulding machine. Mold designers, planners, and specialists have been working on the presentation of cooling systems for a long time, despite the fact that the complexity of cooling channels is severely limited by the creation capacity of classic straight boring techniques. This study examines the usage of conformal cooling diverts in injection moulding for a variety of crosssectional forms, positions, and measurements, attempting to determine which conformal cooling arrangement produces the greatest results in comparison to traditional cooling channels. SOLIDWORKS Plastic simulation software was used to create a mould with efficient cooling channels, as well as a full finite element analysis and flow simulation for a variety of plastic parts. Taking everything into consideration, simulation and investigational confirmation demonstrate that conformal cooling channel moulds with optimum cross section, diameter, and location reduce crucial measures of process length as well as the quality of plastic components produced by injection moulding. Keywords: Conformal cooling channel, plastic material, multi cavity, Moulding, SOLIDWORKS Plastics. INTRODUCTION Injection Molding Injection molding is a very common plastic processing method to convert raw plastics to an object of practical use. It is a common manufacturing process to make consumer products, engineering parts, medical devices etc. About 80% of cycle time is taken up by cooling phase. The cooling system must be able to remove the heat at the required rate so that the plastic part can be ejected without distortion. At the same time, the cooling of the part should be kept as uniform and balanced as possible so that undesired defects such as shrink marks, differential shrinkage, internal thermal residual stresses and warpage can be reduced. Figure 1: Basic components of an injection moulding machine Heat flow in the mould Heat regularly moves from an assortment of higher temperature to a lower temperature body. Temperature distinction between two bodies will decide the progression of hotness. The more noteworthy the temperature difference between two bodies the higher the pace of heat flow between them. Heat can be moved starting with one medium then onto the next in three unique ways: radiation, conduction and convection. Figure: Types of heat flow in a injection mould. Importance of cooling system and Mould cycle time The mould cycle time duration relies fundamentally upon mould cooling configuration, mould material determination, and the plastic material shaped while different variables incorporate the machine speed setting and the technique for ejection from the moulds. In viable applications, the mould cooling stage takes a generous part, by and large from 50 - 80% of the mould cycle time. Fig:1.2 Typical moulding cycle of injection moulding process (in seconds). Conformal Cooling Channel Conformal cooling channel is a cooling passageway which follows the shape or profile of the mould core or cavity to perform rapid uniform cooling process for injection moulding or blow moulding processes. Figure 3 Example of Conformal Cooling Channel Problem Formulation • Plastic moulding process is continue flow process. In this process overall cycle time is very important factor. • Cooling process play a important role in overall cycle time it take 50% to 80% time of all process time. So cooling time reduction in plastic injection moulding process very important factor. • Uneven cooling in in plastic injection moulding process will result of defect in product. • Unsatisfactory cooling also not good for moulding process. • In multi cavity injection machine applying a conformal cooling is difficult task. Literature Review K. Poornima et al. [28] A comparison between straight drilling cooling channels (SDCC) and conformal cooling channels has been carried out in this study. To do this, a multi-cavity rectangular plate with inappropriate draught angles and nominal wall thickness was examined for possible flaws in the design. As soon as the design of the rectangular plate in Pro-E Wildfire 5 was done, Autodesk Moldflow was used to carry out the investigation. The spiral cooling channel was the most efficient in terms of cooling time required. Alban Agazzi et al. [29] A novel technique for determining the cooling system of a 3D industrial item was given. In order to do this, they first developed a control problem for optimal fluid temperature distribution throughout the cooling surface, and then conducted a thermal analysis to determine the placement of isotherms in quasi-stationary thermal zones. Shayfull Zamree Abd Rahim et al. [30] There is a novel design for machined grooves in a square shape conformal cooling channels that has been shown. Warpage and cooling time for the moulded pieces have been investigated by the team of researchers. According to Autodesk Moldflow Insight 2013 simulation results, when compared to traditional straight drilled cooling channels, the conformal cooling channels performed significantly better. Available cooling methods and Importance of Research 1. In injection moulding process, it is undeniably challenging to accomplish effective and adjusted cooling. It is additionally hard to create an ideal cooling design for a plastic part naturally. Due to the multifaceted nature, the mould cooling design in the mould industry is still generally dependent on set up standards, the designer's experience and experimentation procedures. The design may likewise confront the constraints of the abilities and norms of the business sectors just as the capability of the end client. The cooling design tragically, must be set at the finish of design cycle. Mould designers have other rudimentary issues to think about, for example, gate location, ejector pin and runner arrangement for multi-cavity mould before they can design and place cooling channels. So eventually, subsequent to putting different components, little space and adaptability are accessible to plan productive cooling channels. Some designer places however many cooling channels as they could in the mould to get quick and adequate cooling, and have the mould tried to conclude which of them would function well. At the point when no computational analysis and simulation tool is applied, it is typically hard for accessible mould cooling techniques to accomplish uniform and adjusted cooling. 2. Process duration or cycle time, which is crucial factor for mould design, is regularly assessed dependent on a designer's experience and a mix of experimentation draws near. Therefore, many moulds are worked at a significantly longer cycle time than needed which prompts low productivity and quality. As the part geometry turns out to be more complicated, an encounter based methodology turns out to be less possible. Since the experience-based techniques can't plan conformal cooling channels for complex mathematical states of plastic parts, though, proposed conformal cooling channels with legitimate size, shapes and areas could beat these limitations, which will be completely talked about in this theory. Accessible conventional cooling techniques being utilized are straight drilled cooling channels (SDCC), thermal pin, baffles, bubblers, helical channels, heat pipes, milled grooves and heat rods. 3. With the generous advances in Rapid Prototyping (RP) and Rapid Tooling (RT) techniques, a few researchers have transformed these methods into mould making activities. The benefits of Rapid Prototyping and Rapid Tooling techniques are the capacity to abbreviate the lead-time and the capacity to manufacture intricated internal mould cooling system. The conformal cooling channels, which can be fabricated utilizing the Rapid Prototyping and Rapid Tooling, were accounted for to have accomplished better temperature control for shortening the process duration and further develop the quality of product. Notwithstanding, proper cooling channel design and geometric location in the mould concerning diverse moulding material, mould heartiness and mould making costs are a portion of the issues to be beaten utilizing these advancements. In this exploration work, a complete report has been done to defeat a portion of these deficiencies of creating conformal cooling channels. Diverse cross-sectional shapes of conformal cooling channel, their position from moulds surfaces and bi-metallic conformal cooling channel have been entirely explored with complete simulation and experimental confirmation. Research Gap In the Privious study researchers tries to reduce the overall cycle time by chaning parameters like • Using conformal cooling channel instead of conventional straight line cooling channel. • By changing the Profile of cooling channel This steady was Experimental Based Some other changes are also need to be study • Conformal cooling channel in multi cavity plastic injection moulding machine. • Use some more Profile in conformal cooling like polygon, circular. Objective • It is possible to design cooling channels with appropriate cross sections and distances from the hollow surface. • High thermal conductivity mould cooling channels composed of bi-metallic and conformal copper tubing are used in the production of moulds. • Conformal cooling channels may be created using Laser Direct Metal Deposition (LDMD), which is a rapid manufacturing process that can be utilised to construct them. • It has been demonstrated through computational and experimental approaches that conformal cooling channels may reduce cycle times, extend mould life cycles, and enhance the quality of final products. • In Multi-Cavity mould conformal cooling channel is very effective for cycle time reduction. Cooling channel design A plastic bowl made of polypropylene has been chosen as a contextual analysis. Plastic part is of 246 mm diameter, 68mm height, and 2.2 mm thick and it weighs 163 gm. below, shows the part as designed with SOILDWORKS system. Deeply and hole for the part as planned consequently with SOLIDWORKS Plastics system. At last, cooling channel has been intended for core and cavity with clear cut device of SOLIDWORKS framework. In the wake of planning the cooling channel, transient thermal finite element analysis has been done for enhancement of cross section to figure out which cross sectional cooling design gives the best cooling time. Analysis will be examined in a later segment of this part. Design for cross-section Two different kinds of cross sectional areas of cooling channels have been intended for conformal cooling channel. For conventional cooling channel, one sort for example circular has been planned. For conformal cooling, the two cross sectional shapes are circular and polygon as displayed in Figure 3.7. These cross sectional shapes for the conformal cooling channels have been chosen for a similar hydraulic diameter, Dh=10.10 mm, as a benchmark (which is likewise utilized as the cross-sectional measurement of the regular cooling channel by the nearby business). The hydraulic diameter across Dh, [13] is characterized by the accompanying condition (3.1), Dh=4A/P………………………………………………………………..(3.1) Where, A= cross-sectional area of cooling channel, And, P= wetted perimeter of section. CAD Modelling 3-D design of multi cavity mould (Circular Profile) Using SOLIDWORKS Modelling. 3-D design of multi cavity mould (Polygon Profile) Using SOLIDWORKS Modelling Boundary condition 1. Process Parameters 2. Cool Setting Simulation Result 1. Circular Profile Conformal Cooling Channel Flow Results 2. Polygon profile Conformal Cooling Channel Flow Result Result & Discussion • In above simulation we take two type of profile first is circular and other is polygon shape profile. • Simulation was done SOLIDWORKS Plastic. • Result are shown for both circular profile and polygon profile. • Cooling time for circular profile is 34.29 second and for polygon profile cooling time is 49.09 second. • It is clear from above result that in conformal cooling channel circular profile is better than polygon profile. • From this simulation we also conclude that conformal cooling is also effective for multi-cavity plastic mouldig machine.
