Question

What should be the pressure range (in bar) of the gas used in the low-pressure die casting?

(a) 0.3 to 1.5

(b) 2 to 10

(c) 10 to 30

(d) 30 to 50

The question was posed to me during an internship interview.

This is a very interesting question from Low Pressure Die Casting topic in section Special Casting Techniques of Casting-Forming-Welding I

Answer 1

Right choice is (a) 0.3 to 1.5

For explanation: In low-pressure die casting, compressed gas is basically used at a pressure typically ranging from 0.3 to 1.5 bars to force the molten metal to rise slowly through the ceramic riser tube that is connected to the mould. Pressure should be below atmospheric pressure to easily pull the molten metal into the cavity.