Author Question: What method is used in injection blow molding to achieve the type of part wall thickness control ... (Read 47 times)

schs14 · **on:** Aug 19, 2018

What method is used in injection blow molding to achieve the type of part wall thickness control that can be obtained in programmable parisons?

What will be an ideal response?

Question 2

What is the advantage of a programmable parison device?

What will be an ideal response?

xoxo123 · **Reply #1 on:** Aug 19, 2018

Answer to Question 1

Programmable parisons only have meaning in extrusion blow molding because they are made with a movable mandrel in the extrusion die. However, a similar effect can be achieved in injection blow molding if the core pin of the preform

mold cavity is shaped. This shaping will create some thick section of the preform which can be placed in the locations that will travel the farthest in the mold.

Answer to Question 2

Programmable devices allow the parisons to have varying wall thickness to compensate for the longer distances of travel required to fill some parts of the mold. The parts made using programmable parisons are, therefore, more uniform in wall thickness.