**7. Case study 2**

The interconnection of coaches by a coupling makes a train. In earlier days screw coupling was used. Screw coupling has certain inherent limitations like haulage of longer train is not possible in freight, climbing of coaches in collisions and derailment, life of shunting staff at risk and higher maintenance staff requirement. On the other hand, central buffer coupling (CBC) has advantages like the coupling is safe for shunting staff, less time is required since quick detachment is possible, less staff for uncoupling, the coaches do not climb on each other during accident and hence prevent damage to life and property during accident. The CBC has three major components, knuckle, coupler body and yoke. The CBC is a cast product. In this present case study the use of casting simulation software on a CBC product is demonstrated. The simulation software is capable of indicating the loop-holes of

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is discussed here.

*Product with shrinkage defect and linked simulation*

**Figure 2.**

**Figure 1.**

*Scheme of wedge block preparation*

the existing design and the caveats can be ironed out by proper methoding. Final simulation results show that there is hardly any detrimental defect in the cast part and thus a huge cost for trial and error is saved. To demonstrate the role of methoding and solidification criterion on casting defects, one crucial industrial case study

The foundry is producing three major components of CBC i.e. coupler body, knuckle and yoke in a single mould. Cast Steel (ASTM M-211 GRADE-E) was used as the casting material and green sand under high pressure moulding system was

*Simulation and Validation of Castings in Shop Floor DOI: http://dx.doi.org/10.5772/intechopen.94596*

*Simulation and Validation of Castings in Shop Floor DOI: http://dx.doi.org/10.5772/intechopen.94596*

*Casting Processes and Modelling of Metallic Materials*

• Ingate of the casting is to be designed

• Virtual mould is to be created

• The 3D model in. STL format is required to be imported

Minimum wall thickness and Weight of the component.

thermo-couples are to be set on some strategic locations

input. Heat transfer coefficient is to be provided thereafter.

time, solid temperature, details on shrinkage condition etc.

and productivity increases with stack moulding approach.

• Material and initial temperature are to be provided

• Meshing is done. It is dependent on three parameters, Geometry complexity,

• To obtain the graphcal representation of simulation behavior, some virtual

• Next, the solver environment is to be declared. Here some typical inputs are required from users. For example, the analysis terminate conditions are flow rate and time are to be declared. Input wall condition is to be provided. For this, there may be two situations like slip condition and no-slip condition and hence the input value will vary between 0-1 respectively. For sand casting input wall value is between 0.4 to 0.6 whereas for die casting the value is 1. Next, the riser material type, whether it is exothermic or not is to be given as

• Once done, the software will provide the results with flow temperature, solid

For preparing some wedge blocks, a scheme of preparation mechanism used by a manufacturing company is shown in **Figure 1**. The product being manufactured with the existing method design contains shrinkage defect. The simulation result also confirms the same. The shrinkage defect and its associated simulation result are shown in **Figure 2**. Therefore to eliminate the defect and also improve overall process associated with the production stack moulding is adopted as shown in **Figure 3**. Due to this modification various related parameters also improve as shown in **Table 1**. The techno-economy analysis of wedge casting per ton shows that cost per piece reduces

The interconnection of coaches by a coupling makes a train. In earlier days screw coupling was used. Screw coupling has certain inherent limitations like haulage of longer train is not possible in freight, climbing of coaches in collisions and derailment, life of shunting staff at risk and higher maintenance staff requirement. On the other hand, central buffer coupling (CBC) has advantages like the coupling is safe for shunting staff, less time is required since quick detachment is possible, less staff for uncoupling, the coaches do not climb on each other during accident and hence prevent damage to life and property during accident. The CBC has three major components, knuckle, coupler body and yoke. The CBC is a cast product. In this present case study the use of casting simulation software on a CBC product is demonstrated. The simulation software is capable of indicating the loop-holes of

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**6. Case study 1**

**7. Case study 2**

**Figure 1.** *Scheme of wedge block preparation*
