SUCTION MOULDING , ADVANTAGES AND ITS DISADVANTAGES

In this method, a Vacuum is created by withdrawing air from the mold space. Subsequently molding sand is sucked in and the cavity is filled up. The sand can there after be rammed in the pattern. the process is used for casting iron, steel and aluminum. The weight of casting ranges from 200 gm to 120 kg. Mold is used once and is made from wet artificial crashed sand. The process is different from vacuum molding where plastic sheet is vacuum molded to the contour of the pattern, back filled with fine grained binder free quartz sand and sealed with another plastic sheet. The mold is constantly connected to a vacuum source before, during and after the casting.

Advantages of the suction molding process are :

1. Optimum mold compaction around the pattern.

2. Decreasing hardness of compacted sand from inside to the outside.

3. High surface quality.

4. Reduced cleaning.

Disadvantages of the process are :

1. High Cost Of Manufacturing .

2. Change - Over Time High .

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Mechinopedia For Mechanical Engineers

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