Question

Which of the following materials is used for imparting strength and collapsibility in core sand during core making process?

(a) Molasses

(b) Core oil

(c) Sulphite binder

(d) Thermo-setting resin

The question was posed to me by my college director while I was bunking the class.

This intriguing question comes from Core Making Machines in portion Foundry Mechanizations of Casting-Forming-Welding I

Answer 1

The correct choice is (d) Thermo-setting resin

For explanation: Thermo-setting resin is very popular in core making because it imparts high strength, collapsibility to core sand and it also emits a minimum amount of mould and core gases which can produce defects in the casting component. The most general binders under this category are phenol formaldehyde and urea formaldehyde.