Question

2 of 7 Fit to page CD Page view A' Read aloud Add notes P (3 marks) C. The following chart, Figure Q1C (i) shows production steps in a typical sand-casting operation, -- Pattern making Pattern - Core making Gating system Sand Mold Heat treatment i Melting of metal Pouring into mold Solidification and Shakeout and removal of risers and gates Cleaning and Inspection cooling finishing Furnaces Additional Defects heat treatment Pressure tightness Dimensions Figure Q1C (1): Outline of production steps in a typical sand-casting operation Based on Figure Q1C (1), translate the above outline of production steps for preparing green sand mould of a given product as shown as dimensionless product drawing in Figure Q1C (ii) to fulfill a batch quantity order. Provide sufficient sketches and labels with a short precise note to explain the sand molding production for the given case study. (8 marks) (a) Section view (b) Isometric view

Answer 1

The team (1) PATTERN: - A pattern is a replica of the object to be cast, used to prepare the cavity into which molten materbe will be poured during casting process Patterns used in sand casting imaybe made of wood, metal, plastics, etc. Pattern making:- A replica of different material (maybe wood, metal.) is made with outer dimensions as shown Core making:- A core is a device used to produce internal calities. A core here can be made at material for ease of use. Love is made of easily cleformable inner dimensions of required shape as outer dimensions of core. that can be TITA product required torre Gating system: Rises cup chaplets Sprue core caring all passes toenter Runner passage ways through which the molten metal the mould caulily. It composed of Puring basin Spove , Runnes, cates, Pisces, core jete Cņi) Molding scend : Molding sand also kreken foundry sand, is asand that when moistened and compressed or oiled or heated tends to pack well & hold its shape. sand in There are several types of moulding sand -areen sand sry sand - Cocim scend - Facing Sand - System sand Palting sand -Core Sandete. In process of prepcuting amould, sand is choosen as per requiremat.

(v) Pouring citt) Mold- Mold is made by using peket proper sand sand & theesundega several smelding process like ramming. Mold System is thus prepared as that of gating System previously planned (iv) Melting of metad - Meteit is melting above certain temperatures in furnace the depending on metal properties. into mold Thus formed molten metal is poured into mold through pousing basin of the gating system. (vi) sdidifcation and cooling: The excess molten metal poured exells through the rises, After mold cavily is I completely filled. Molten metal is to settle down and solidity As solidification results in contraction some allowances must be made during pattern making allowance here also include machining alboa shakeng allowance, dis hortionallacaná etc). This molten metal is solidified and cooled (takes a shape). (vii) Shakeover and removal of riseys&gedes- After proper cooling of metal, mold sand is removed and core is detormed and removed casetully. It takes the shape as shocon. left h Hallow lemphy Excess pasts this formed like gates, rises are removed. Thus aftel removing, it would be asshole in the fig. 3 (viii) Heat treatment: It is an indehoice, thermal and metal working process used to ulter physical, and sorreres chanicas properes of a modeid. This step is not mandatory

cent suickHeat treatment is used to refine group shuchre to relieve internal stresses and to increase hored neis and toughness. Through heat hoahm is not a mandohory processes in ordee relieve internal stresses it would be better to make heeet treated (ix) Cleaning and finishing - It furthes undergoes final finishing processes for accuracy and preúsionlike machining gosrding,ete. In this process coft er finishing and eventing product undergo es Heat treatment. Ex) Inspection: Thus manufactured produt is tested Cinspected) for the required factors that include Dimensions, withetanding pressures, etc. The products that fail inspection all considered to be detects.

Step1_ A pattern and core are made as per given dimensions with considering allownaces with materials like wood,metal, plastics ,etc

Gating system is thus designed as per requirement.

Step2_Moldsand is thus choosen as per requirement and made with mixture of substances at exact proportions.

Step3_Mold is prepared by using the mold sand thus prepared and gating system designed using several processes that include ramming.

Step4_Metal of which product is required , is heated at certain high temperatures above melting point temperature as per metal properties in furnace

Step5_Molten metal thus formed by heating in furnace is poured into mold through pouring basin

Step6_Metal gets solidified and cooled after sometime

Step7_Mold sand is removed by shaking it out. Excess formed parts like risers,runners etc are removed by machining processes.

Step8_Product undergoes heat treatment process for betterment in internal structure.

Step9_Product thus formed is cleaned and finla finishings are done like grinding with very fine grades and additional heat treatment is done to the final product.

Step10_Product is inspected as per the purpose of the product and undergoes several testings like pressure test dimension test etc. The products that fail inspection are considered to be defects.