# GATE Questions & Answers of Design of Patterns, Moulds and Cores

## What is the Weightage of Design of Patterns, Moulds and Cores in GATE Exam?

Total 5 Questions have been asked from Design of Patterns, Moulds and Cores topic of Casting, Forming and Joining Processes subject in previous GATE papers. Average marks 1.60.

A sprue in a sand mould has top diameter of 20 mm and height of 200 mm. The velocity of the molten metal at the entry of the sprue is 0.5 m/s. Assume acceleration due to gravity as 9.8 m/s2 and neglect all losses. If the mould is well ventilated, the velocity (upto 3 decimal points accuracy) of the molten metal at the bottom of the sprue is  ________________m/s

Gray cast iron blocks of size 100 mm $×$ 50 mm $×$ 10 mm with a central spherical cavity of diameter 4 mm are sand cast. The shrinkage allowance for the pattern is 3%. The ratio of volume of the pattern to volume of the casting is ________

In full mould (cavity-less) casting process, the pattern is made of