High pressure die casting or HPDC

Block diagram of HPDC process is shown below, molten metal is poured into the cylinder where the piston force the molten metal to flow into the mould cavity.

High Pressure Die Casting
Block Diagram of High Pressure Die Casting Process


Once the poured metal inside the mould cavity get cold and take shape the die halves got opened and the moulded component come out. And the process continues.


Low Pressure Die Casting or LPDC

Working of LPDC process is explained through the block diagram below:

Low Pressure Die Casting
Block Diagram of Low Pressure Die Casting

Here, the molten metal (3) is forced by the pressure of gas passed through the pipe (10) into the mould cavity (11) against the gravitational force. Once the mould cavity is sufficiently filled and the component got cooled enough, the die halves (1 &2) got opened and the moulded part got ejected out.


Comparison of High Pressure Die Casting (HPDC) vs Low Pressure Die Casting (LPDC)

Tooling Cost High Low
Equipment Cost High Low
Production cost / unit Low High
Production Rate High Low
Porosity High Low
Surface finish High Low
Suitable for Al & Zi alloys, Component  with high surface finish

low fatigue strength: carburetor, distributor bodies,

switch gear housing etc.

Al & Zi alloys, Component with low surface finishhigh fatigue strength: auto wheels, gearbox,

electric motor stator etc.

One Reply to “HPDC vs LPDC”

  1. Note: The porosity in the cast part will be low in HPDC than the LPDC.

    It is given in the other way, kindly correct it.

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