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K. Santhy and D. R. Rajkumar
1 Introduction
Casting is widely used in an industry to make large and or complicated components which cannot be obtained by metal forming techniques. The advantage of
casting is inexpensive and relatively simple. Particularly sand casting has its own
traditional history. But, cast product always carries risk of failure during the manufacturing process. The good sand casting component depends on many parameters
such as designing of component, proper preparation of mould, pouring temperature
of metal, and property of sand. The knowledge of process parameter and its consequence in defects help out to minimize the rejection rate of the products. Present
work concentrates on the defect analysis of harvester cup, chain link and non-return
valves using process parameter in an industry. A harvester cup is used as a guide way
in harvester vehicle. The chain link is used over the conveyer belt for transferring
like coal in a thermal plant. Both the components are made up of ductile cast iron
and casted in single process. Using solidworks software [1], harvester cup and chain
link are shown in Fig. 1a, b, respectively. Check valve is used in the compressor
to maintain the diverse pressure in various parts. The check valves are obtained by
non-return valves. Figure 1c shows the non-return valves outline using solidworks
[1]. The non-return valves are made up of grey cast iron. The process flows followed
by the foundry for production of grey and ductile cast iron are shown in Fig. 2. Both
the ductile and grey cast iron have significant metallurgical properties at low cost [2,
3]. Magnesium (Mg) has high affinity towards sulphur and oxygen. However, Mg
is added purposely in induction furnace to remove the impurities such as sulphur
and oxygen which is called as magnesium treatment. The shape, size and quantity of
graphite and or cementite play a vital role in the properties of cast iron. In addition,
the length of graphite flake plays important role in damping nature of the component
[4]. Normally, inoculants added for graphite nucleation. In grey cast iron, inoculation agent such ferrosilicon is added in ladle to avoid fading effect. Ductile cast
iron requires both spheroidizing and inoculation to get required microstructure and
properties. To remove impurities like sulphur and oxygen and spheroidizing, magnesium treatment is required for ductile cast iron. The choice of magnesium treatment
Fig. 1 Cast components. a Harvester cup, b chain link and c non-return valves using solidworks
software (Solidworks 2015)
K. Santhy and D. R. Rajkumar
1 Introduction
Casting is widely used in an industry to make large and or complicated components which cannot be obtained by metal forming techniques. The advantage of
casting is inexpensive and relatively simple. Particularly sand casting has its own
traditional history. But, cast product always carries risk of failure during the manufacturing process. The good sand casting component depends on many parameters
such as designing of component, proper preparation of mould, pouring temperature
of metal, and property of sand. The knowledge of process parameter and its consequence in defects help out to minimize the rejection rate of the products. Present
work concentrates on the defect analysis of harvester cup, chain link and non-return
valves using process parameter in an industry. A harvester cup is used as a guide way
in harvester vehicle. The chain link is used over the conveyer belt for transferring
like coal in a thermal plant. Both the components are made up of ductile cast iron
and casted in single process. Using solidworks software [1], harvester cup and chain
link are shown in Fig. 1a, b, respectively. Check valve is used in the compressor
to maintain the diverse pressure in various parts. The check valves are obtained by
non-return valves. Figure 1c shows the non-return valves outline using solidworks
[1]. The non-return valves are made up of grey cast iron. The process flows followed
by the foundry for production of grey and ductile cast iron are shown in Fig. 2. Both
the ductile and grey cast iron have significant metallurgical properties at low cost [2,
3]. Magnesium (Mg) has high affinity towards sulphur and oxygen. However, Mg
is added purposely in induction furnace to remove the impurities such as sulphur
and oxygen which is called as magnesium treatment. The shape, size and quantity of
graphite and or cementite play a vital role in the properties of cast iron. In addition,
the length of graphite flake plays important role in damping nature of the component
[4]. Normally, inoculants added for graphite nucleation. In grey cast iron, inoculation agent such ferrosilicon is added in ladle to avoid fading effect. Ductile cast
iron requires both spheroidizing and inoculation to get required microstructure and
properties. To remove impurities like sulphur and oxygen and spheroidizing, magnesium treatment is required for ductile cast iron. The choice of magnesium treatment
Fig. 1 Cast components. a Harvester cup, b chain link and c non-return valves using solidworks
software (Solidworks 2015)