Blow molding - a thermoplastic resin is heated to a molten
state and extruded through the tooling die head to form a hollow tube called a parison.
The parison is dropped between two mold halves, which close around it. The parison is
inflated and the plastic solidifies as it is cooled inside the mold. The mold opens and
the finished component is removed.Dip molding - a
heated metal tool, shaped to the internal dimensions of the required part, is immersed
into a tank of cold liquid PVC (polyvinyl chloride), or plastisol. The tool is removed
from the dip tank, carrying with it a coating of plastisol. The coated metal tooling is
then placed in an oven for curing. After cooling, the plastisol part is removed from the
metal tooling as a finished product.
Dual Process™ Overmolding
- a patented technology used to connect materials with differing hardness, flexibility
and temperature properties along the length of a part. For example, a flexible rubber cuff
end is overmolded onto a rigid blow molded air duct. The finished product produces one
continuous assembly, with a tightly sealed, durable union of the multiple parts.
Elastomer - a material that at room temperature can be stretched repeatedly to
at least twice its original length, and snaps back to the original length upon release of
stress.
Emabonding - a method of welding by inductively heating a metal filled gasket
pressed between two parts.
Flex modulus - ratio of stress to strain in a part under flexural lead.
Hot plate welding - the joining of two parts by simultaneous application of heat
and pressure via a removable hot plate.
Izod impact - a measure of the energy needed to produce a crack in plastic or
metal parts.
Olefins - various long-chain synthetic polymers (ex. polyethylene and
polypropylene).
Pad printing - an inked image is transferred from a photo-etched plate to a
thick, soft silicone pad. The pad is then pressed against the plastic part. The pad can
wrap itself as much as 180° around a small object, and ink coverage is excellent. One
color is done at a time, but registration between colors is good enough to allow
four-color process printing.
Parison - in blow molding, the hollow tube of plastic melt extruded from the die
head, and expanded within the mold cavity by air pressure to produce the molded part.
Roll printing - a form of rotational screen-printing where the print image is
applied to the circumference of a plastic part as it is rotated on a supporting metal bar.
Silk screen printing - a decorating stencil of taut woven screen is secured in a
frame. Nonprinting areas of the screen are coated with a masking material. The screen is
placed over the object to be printed and a squeegee forces ink through the noncoated areas
of the screen.
Tensile Strength - the maximum stress that a material can withstand without
breaking.
Vicat Softening Point - the temperature at which a flat-ended needle of one
square millimeter will penetrate a thermoplastic specimen to a depth of one millimeter
under a specified load and uniform temperature rise.
