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GATE 2019 ME (ME2) – Question 60

Casting, Forming and Joining Processes · Casting: patterns, moulds, cores, solidification, riser and gating design, defects · 2 marks · Numerical answer

The shown metal-block pouring arrangement has negligible friction. With g = 9.81 m/s², find time to fill the 40 cm × 30 cm × 15 cm mould cavity (s), to two decimal places.

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Correct answer: 28.80 to 29

Explanation

Bernoulli gives sprue exit speed $v=\sqrt{2gh}=\sqrt{2(9.81)(0.20)}=1.98091$ m/s. Area is $A=\pi(0.02)^2/4=0.000314159$ m². Cavity volume is $0.4(0.3)(0.15)=0.018$ m³. Filling time is $V/(Av)=\mathbf{28.92}$ s.