During the annular extrusion, the parison
swells and sags as it exits the die.
"Depending on the processed material, speed and ambient conditions, high static charges can build up on the extruded parisons
during the blow moulding process," explained Massimo Davoli, Global Product Manager for Shuttle Blow Moulding at Uniloy.
The constant spread of ions ensured total neutralisation from the parison
extrusion head to the top of the mould tool, and therefore avoiding further oscillation and cases of failed delivery.
To optimize parison
forming, Interface Catheter Solutions developed a computerized parison
stretcher that provides accurate, repeatable results for neck-down tubing in preparation for balloon forming.
In more complicated designs, it may not be possible to simplify using convoluted sections; the flexibility of convoluted sections is not desired for functional reasons, or tilting the duct axis relative to the parison
axis cannot achieve a proper molding.
The forming of glass containers by the "press and blow" process can be divided into five main steps: gob formation at the feeder, transfer and loading of the gob into the blank, pressing of the parison
, inversion of the parison
into the blow mold, and the reheat and final blowing of the container.
Furthermore, a method that focuses on visual likeness without considering context, ignores how "what looks like the same object can be structured into two different cultures in such a completely different way that the surface likeness is insignificant in com parison
with the deeper symbolic differences" (25).
A new parison
control package for blow molding machines, according to its manufacturer, Siemens Energy and Automation Inc.
Even modified PC resins have such a high melt viscosity it's not possible to form a parison
suitable for blow molding.
The wheel slows to match the parison
speed on closing and then speeds up to pull away from the head and insert the blow pin.