Pressure die casting Introduction, working, advantages and disadvantages

Pressure die casting

• In pressure die casting molten metal is forced into a die under pressure. 
• The die is made of two parts. 
• One part is stationary and other is movable. 
• The permanent mould is called as die.

There are two types of pressure die castings

• Hot chamber die casting
• Cold chamber die casting

Hot chamber die casting

• Heating chamber is used to melt the metal.
• Injector or Gooseneck is placed on the top of the chamber.
• Plunger is placed in the gooseneck vessel
• When the plunger moves upward, the molten melat files into the vessel.
• When the plunger moves downward the molten metla injected into the die under pressure.
• After the cooling dies are dismantled
• And finally casting is moved from the die

Cold chamber die casting

• In cold chamber ie casting heating chamber not placed
• Metal is heated in the furnace
• Fixed and movable die are placed in vertically
• Ram is provided to inject the molten metal
• Molten metal is poured in shot chamber
• Ram is used to fill  the die
• After the cooling dies are dismantled
• After the solidification casting is removed.

Advantages

• Suitable for mass production
• Good surface finish
• Low casting defects
• Accurate casting

Disadvantages

• Cost of die is more
• Not suitable for large castings