question_answer

Consider the following statements1 in respect of investment castings:

1. The pattern or patterns is/are not jointed to a stalk or spure also of wax to form a tree of patterns.

2. The prepared moulds are placed in an oven and, heated gently to dry off the invest and melt out the bulk of wax.

3. The moulds are usually poured by placing the moulds in a vacuum chamber.

Which of the statements given above are correct?

A) 1 and 2 only                 

B) 1 and 3 only

C) 2 and 3 only                 

D) 1, 2 and 3