Analysis and Optimization of Various Mould Attributes in Sand Casting

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1 Analysis and Optimization of Various Mould Attributes in Sand Casting G.Mahesh 1, K.Sai Krishna 1, S.Naveen Kumar 2, S.Suresh 2, S.Sanjay Kumar 2, 1 Assistant Professor, Saranathan College of Engineering, Tiruchirapalli. 2 Final year Mechanical Engineering, Saranathan College of Engineering, Tiruchirapalli. ABSTRACT The paper analysis about the suitable composition and properties of the green sand in the casting process the properties which affect the quality of casting in green sand mould are green strength, composition and other which are usually depend on the input parameter. The input parameter which are complex in mature are sand grain size, shape and clay the outermost of the specific mould properties of given sand mould is mainly depends on sand composition the moulding moisture composed of zircon bentoniteand moisture a sample of sand is taken with 70 to 90 % of zircon 5to 15% of bentonite clay 3 to 7 % of moisture content and 15% of other composition such as sludge,austenite, graphite are added. In this work an effort has been done to get the optional setting of the green sand mould of gunmetal by arranging the input parameter by the subsequent setting by design of export approach by fixing one parameter by varying the other parameter to get 18 sand composition from which the finest quality characteristics of the gunmetal was found NDT is conducted successfully on the material having more hardness. Keywords :Moisture Content, Clay Content, Green Sand, NDT 1 INTRODUCTION The main purpose of the sand is to provide a product with good quality and low cost. In sand moulding preparation the important parameters are clay content, moisture content and green strength. The gases are removed from the casting depends on the moulding sand parameters which plays an important role in sand casting process. In addition to the cost importance of casting has been given superiority. The improper mould preparation arises 40-70% of defects. The composition of moulding sand is selected by foundry man. In this process the optimum results of a riser design and optimum melting parameters are used. Priyank et al (2015) investigated the optimal sand casting process parameters by DOE and ANN and reported that the vent hole was mostly used to exhaust the gases from the green sand. Paul De Garmo (2011) determined the yola sand properties and possessions of moisture content. The yola natural sand has been analyzed for the variation of moisture content range from 1 to 9 %. The author concluded that the optimum results of this experimental investigation had compression strength of KN/m2 and 5 % of moisture content. Farzaneh F.M. et al (2016) investigated the thermal behavior of the Casting/Chill material A319 alloy in sand casting process. The authors concluded that temperature plays a major role in the sand casting process. NoorulHaq et al (2010) calculated the optimization of CO2 casting process by using the Taguchi s Method. The input parameters were optimized to improve a high quality in final products. It shows the varieties of defects were investigated and the optimum results were also recommended. The components like zircon and bentonite clay properties were selected in addition to sand mix at weight percentage. The research targets on 1335 G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar

2 sand mold properties for aluminum alloy casting. The physical properties and compositions were evaluated for silica sand in various industries Saliu et al (2014). Moulding sand properties are influenced by the variation in the amount of additives and ingredient and the type of the additives. One of such additives is coal dust, clay and corn flour which also included water and some binders. Imported binders and synthetic sand are used in most of the production units such as Foundry industries in Nigeria CharnnarongSaikaew (2012). It also states that various types of sands are used in foundries for the manufacture of moulds. It is also analyzed that the more easily available green sand are widely used and its forms such as shell moulding sand, core sand and cement bounded sand and dry sands are used for special purposes The qualities of the casting are controlled by the factors such as the permeability, moisture, mould hardness, shatter index, compatibility and green compressive strength in both type of moulding sands HimanshuKhandelwal (2016). These factors are again depended on the parameter such as the properties of the binder, grain size and the amount of water used. The green sand properties like grain fineness number, percentage of clay, percentage of water are analyzed with the help of regression equation developed in GA and PSO B. Surekha (2012). The control f actors like green compression strength, permeability, hardness have been considered. John O. OJI et al (2013) determined the hardness and impact energy of aluminum alloy with main parameters such as mould temperature, pouring temperature and runner size are considered. The optimum results are carried out by taguchi experimental design approach. Mekonnen. L et al (2012) studied the single and double blank aluminum investigated the surface defects and casting yield. The chemical composition of grain size, clay content, moisture content, ramming, sprue size, riser size and diameter and thickness ration of blank are considered. The taguchi robust method is used for this work and obtained the better result for this aluminum blank. S. Guharaja et al (2006) analyzed the casting defects of characteristics of Spheroidal Graphite (SG) cast iron. The taguchi method used for this work and reduced the casting defect. It is considered the input parameters like green strength, moisture content, permeability and mould hardness. The out parameter is casting defect. N. Nagurbabu, et al (2007) determined better clay bounded modeling sand mix by ANN and Neuro fuzzy model. The input parameters are clay, coal dust, moisture and pouring time were considered. The output results of permeability measured by the ANN approach. SHI Dequan et al (2012) analyzed the effect of mixing the green sand prosperities by orthogonal array of L27. The input parameters such as feeding sequence, premixing time, permeability and green strength are also considered. The result concluded that the optimum time calculated for mixing the clay and coal. In casting process sand is one of the most essential moulding materials. Green sand, facing sand, loam and core sand are the different names of sand. Sand contains silica and clay to provide and to offer tenacity. Silica grains are intractable and have no cohesion. Clay is a very small particle powder, is refractory and when soaked is adhesive and plastic. The different levels of proportions are added for these ingredients. The various sizes of silica grains mixtures are used for different application. 2 EXPERIMENTAL PROCEDURE When the molten metal is poured to the mould cavity the volatile gases are generated and travel through the sand cavity. Green strength plays a vital role in escaping the gases from the mould box. Gases can freely escape from the mould box with the help of pores and grains. Therefore given green strength depends on the size of pores, total volume and grains. Green strength also influence the binder, water additions, sand mix, mulling time and the bulk density of the sand mix. The perfect geometry is necessary for mould cavity and riser and gating system.green strength increases when clay content and water of sand increases. The higher strength of green sand will affect the casting material and also heat transfer. A quality casting can be produced by proper selection of green strength. The green strength is taken by shore A dial is used for this investigation as shown in figure G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar

3 Figure 1 Green strength measurements (shore A) The green strength is calculated in several points from both cope and drag and average is taken for the investigation. The strength is decided to fix from 50 to 70 for this investigation. 2.1 SIGNIFICANT OF MOISTURE AND CLAY CONTENT In sand casting clay is used as binding agent to adhere the moulding sand asmold must keep its shape throughout the casting operation. The clay alone can t develop bonds among sand grains without the pressure of moisture content in moulding sand and cone sand. As the coal content increases the permeabilitydecreases. In initial green compressive strength increases with increase in clay content, but later after a certain value its starts decreasing. Figure 2.Moisture and Clay Content The purpose of moisture content is easy to make the perfect shape of mould geometry, sprue, riser and gating system. The percentage of moisture content is added in all particles in the sand and it has been below the atmosphere temperature. Another important factor of the moisture content is used to binding appropriately for all composition of sand like bentonite clay, sand and other particles. To improve the directional solidification in casting process the percentage of moisture content should be maintained G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar

4 3. RESULT AND DISCUSSION Generally the analytical method to statistically validate the significance of the relationship between independent (input) variables to response variables (output variables) is Response Su rface Methodology (RSM). The sets of observed samples are used for deriving information about the properties of random process. A mathematical representation model is constructed for most of the statistical based investigation. In this system, the relationship between y and values might be known. Then, a model is written in the form, y = f (A 1, A2,..,A n) + ɛ (1) Where ɛ characterizes noise or error observed in output y. If we signify the expected output as, E(y) = (A 1,A 2,..,A n) = y (2) So the surface is represented by, y = f (A 1,A 2,..,A n) (3) In RSM, experiments are performed using CCD matrix to develop a second order response model as: y = A 0+A 1x 1+A 2x 2+..+A 11x 12+A 22x 22+A 12x 1x 2+..+A n-1, x n-1x, (4) Where y is response and xi are different factors. The regression coefficients can be computed by last square method. Statistical analysis is used for signifying of factors and their interactions. Using the above response model optimum value of responses and optimal setting of parameters can be computed. Table 2 Input Variables and Output Responses for Design of Experiments Run Moisture Content Clay Content Green Strength Hardness Surface Roughness % % Shore-A BHN microns G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar

5 The table2 shows the experimental value for Gun metal for various input and output responses. The experimental results of this investigation are given in Table 2. Analysis was performed by using the Design of Experiments Minitab17 software. In this section, the part of experimental investigation contains Moisture content, Clay content, Green Strength, Hardness and surface Roughness. The experimentation was conducted for 17 run. The regression Equation are Hardness = * Moisture Content * Clay Content * Green Strength * Moisture Content * Clay Content * Moisture Content * Green Strength * Clay Content * Green Strength * Moisture Content^ *Clay Content^ * Green Strength^2 Surface Roughness = * Moisture Content * Clay Content -4.11* Green Strength Table 3 :Response table for Sand parameters Source SS Hardness Model A-Moisture Content Gunmetal D O F MS F p SS B-Clay Content Surface Roughness D O F MS F p < < < E E C-Green Strength AB AC BC Residual Cor Total CONTOUR PLOTS Figure 3: Contour plot for hardness and surface roughness of gun metal 1339 G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar

6 The results of the contour plot determined that Moisture content plays a major dominating role on the hardness and surface roughness of gun metal as shown in Figure 6.5. The hardness value has a maximum value of 97 BHN and minimum value of 73 BHN. The surface roughness of gun metal obtained from the experimentation has the maximum value of microns and has a minimum value of microns. Figure 4 Effect of Moisture content, Clay content and green strength on hardness and surface roughness of gunmetal The figure 4 shows the effect of moisture content, clay content and green strength on hardness and surface roughness of gunmetal. In the beginning, the hardness is very low at clay content is 5.5 % - 7 %. The hardness is increased with respect to increase in clay content and increase in green strength. Incase of surface roughness the surface roughness is low having 1.5 microns at clay content 7.5%. the surface roughness gets increased with increase in clay content and increase in green strength 4.CONCLUSION Result of ANOVA reveals that moisture content is main parameters, which has greater influence on the sand casting. In the gunmetal, the lowest clay content and highest moisture content is achieve the better hardness and the highest green strength and lowest moisture content achieves the good surface finish. The best sand parameters in sand casting are given in table 3 Table 3 Optimum Sand Parameters in Sand Casting Number Moisture Content (%) Clay Content (%) Green Strength (shore A) Hardness (BHN) Surface Roughness (Microns) REFERENCES 1. Priyank V, Parekh and Dr, J,A, Vadher, Optimization of green sand process parameters by Taguchi method and Artificial Neural Network, Journal of Modern Engineering, Research, Paul De Garmo, E,J,T, Black, Ronald A, Kohser, Materials and Processes in Manufacturing, Technology & Engineering pages, G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar

7 3. Farzaneh F,M, L, S, Kokhan, Determination of the hardness and the mechanical properties of steel during melting, secondary refining, and continuous casting in an arc-furnace shop, Russian metallurgy, Volume 2016, Issue 13, pp , NoorulHaq, A, S, Guharaja, K, M, Karuppannan, Parameter optimization of CO2 casting process by using Taguchi method, International Journal on Interactive Design and Manufacturing (IJIDeM), February 2010, Volume 3, Issue 1, pp SaliuOjo Seidu1, Bolarinwa Johnson Kutelu, Effects of Additives on Some Selected Properties of Base Sand, Journal of Minerals and Materials Characterization and Engineering, 2014, volume 2, CharnnarongSaikaew, SermsakWiengwiset, Optimization of molding sand composition for quality improvement of iron castings Applied Clay Science (2012) HimanshuKhandelwal, B, Ravi, Effect of molding parameters on chemically bonded sandmold properties, journal of manufacturing process, volume 22 (2016) Surekha B, &Lalith K, Kaushik&Abhishek K, Panduy, Multi-objective optimization of green sand mould system using evolutionary algorithms, International Journal of Advanced Manufacturing Technology, (2012) 58: John O, OJI, Pamtoks H, Sunday, Omolayo M, Petinrin, Adelana R, Adetunji, Taguchi Optimization of Process Parameters on the Hardness and Impact Energy of Aluminium Alloy Sand Castings, Leonardo Journal of Sciences, p, 1-12, MekonnenLibenNekere, Ajit Pal Singh, Optimization of aluminium blanks sand casting for process by using Taguchi Robust Design Method, International Journal for Quality research Vol,6, No,1, 2012, Guharaja, S, A, NoorulHaq, K, M, Karuppannan, Optimization of green sand casting process parameters by using Taguchi s method, International Journal of Advanced Manufacturing Technology (2008) 30: Nagurbabu, N, R,K, Ohdar and P,T, Pushp, Application of Intelligent Techniques for Controlling the Green Sand Properties, 55th Indian Foundry Congress 2007, page Shi Dequan, GAO Guili, DONG Jingwei, Study on Effect of Mixing Process on Green Sand Properties Based on Orthogonal Experimental Method, International Conference on Mechanical Engineering and Material Science ( 2012), page G.Mahesh, K.Sai Krishna, S.Naveen Kumar, S.Suresh, S.Sanjay Kumar