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Pressure Die Casting
Pressure Die Casting
• Pressure die casting is a quick, reliable and cost-effective manufacturing process for production of high volume, metal components that are net-shaped have tight tolerances. • The pressure die casting process consists of injecting under
high pressure a molten metal alloy into a steel mold (or tool).• This gets solidified rapidly (from milliseconds to a few
seconds) to form a net shaped component.
Types of Pressure Die Casting
High Pressure Die Casting• Used for castings requiring tight
tolerance and detailed geometry.• High pressure die casting has
wider application • Nearly 50% of all light alloy
casting production.
Low Pressure Die Casting• Commonly used for larger and
non-critical parts.
• Accounts for about 20% of the total production
Rotor die casting machine•AUTOMATIC ALUMINIUM ROTOR DIE-
CASTING MACHINE ROTOR MAKING MACHINE
Working Principle• ROTOR DIE CASTING MACHINE_HD.mp4
Specification
Requirements for rotor die casting1. Rotor lamination drawing2. Rotor assemble drawing3. Commutator drawing4. Shaft drawing5. Pressing position6. Required productivity7. Other technical requirement
COLD CHAMBER DIE CASTING MACHINE• Cold-chamber die casting is ideal for metals such as
aluminum which have a high melting point. •During this process, metal is liquefied in a furnace at
extremely high temperatures and then ladled into a cold chamber to be injected into the die.
Working principle
Working principle (Contd.,)•During cold-chamber die casting, the molten charge, which
consists of more material than is required to fill the casting, is ladled from the crucible into a shot sleeve where a hydraulically operated plunger pushes the metal into the die. • The extra material is used to force additional metal into the
die cavity to compensate for shrinkage, which takes place during solidification. • The main components of a cold-chamber die casting machine
are shown below. Injection pressure of over 10,000psi or 70,000KPa can be obtained from this type of machine.
Working principle (Contd.,) • The die is closed and the
molten metal is ladled into the cold-chamber shot sleeve.
Working principle (Contd.,)• The plunger pushes the
molten metal into the die cavity where it is held under pressure until it solidifies.
Working principle (Contd.,)
• The die opens and the plunger advances, to ensure the casting remains in the ejector die.
Working principle (Contd.,)• Ejector pins push the casting
out of the ejector half of the die and the plunger returns to its original position.
3000T Die Casting Machine, ZDC-3000TCM
Features Locking force: 3000Ton
Die height: 850-2000mmTie bar distance: 1700x1700mmMax. weight of shot: 38.9kgfMax. casting area: 4256~3242cm2
Horsepower required: 190KVA
Specifications
Specifications (Contd..)
Advantages
•High speed production can be achieved as the whole process is completely automated.• Possible to obtain fairly complex castings than that feasible
by gravity die casting due to the use of the movable cores.•Very small thicknesses can be easily filled as the liquid metal
is injected under high pressure.
•Very good surface finish can be obtained &most of pressure die castings can be directly electroplated without any further processing.• Closer dimensional tolerances & better mechanical
properties can be obtained compared to sand casting.•Very economical for large scale production.
Advantages (Cont.)
Disadvantages• Large capital investment is required to set up a pressure die
casting process.• The die casting machines & tooling costs are very expensive.• Cannot be used for large castings as the casting machine
capacity is limited.
• It is not suitable for all materials because of the limitations of the die materials & the alloys used must have allow melting point.•High porosity is common & heat treatment is difficult.
Disadvantages (Contd..)
Application of Pressure Die Casting •Automotive parts like wheels, blocks, cylinder heads,
manifolds etc.•Aerospace castings.• Electric motor housings.•Kitchen ware such as pressure cooker.• Cabinets for the electronics industry.•General hardware appliances, pump parts, plumbing parts.