Lecture 3-4 Processes

Question 1

What are the differences in positive and negative moulds?

Answer 1

Positive moulds have the convex side of the final product
Negative moulds have the exterior shape of the concave side o

Question 2

What is a common unwanted characteristic when thermoforming?

Answer 2

differences in thicknesses of the final mould

Question 3

Free blowing is a process that

Answer 3

allows products with part spherical features to be formed by simple blow forming of heated sheets of thermoplastic

Question 4

Free blowing can also be used to form

Answer 4

female moulds to be used at a later stage

Question 5

Free blowing is often used in the —— and ——- industries

Answer 5

pharmaceutical, aerospace

Question 6

Polymer casting can be used to produce a sheet by

Answer 6

pouring the liquid polymer onto a moving belt

Question 7

Difference between potting and encapsulation?

Answer 7

Potting - the mould is part of the final product

Encapsulation - the mould is removed to reveal the final product

Question 8

Potting and encapsulation are used commonly in

Answer 8

electrical assemblies - the plastic serves as a dielectric