are Threaded Inserts for Plastic?
Inserts are used to strengthen plastic parts in which screws
are to be installed and removed more than once. Most
made of brass, which provides long thread
life as well as a solid, secure fastening base. Tri-Star's
are also available in aluminum, stainless steel and
free-machining steel by special order.
inserts are commonly used to reinforce two types of plastic:
thermoplastic or thermoset plastic.
Thermoplastics are like
wax. At usable temperatures they are solid, but at elevated
temperatures they get soft and melt. In contrast, thermoset
plastics have a molecularly cross-linked structure which
is permanently “set” into
shape during the manufacturing process.
compounds are generally more resilient than thermosets
well to the ultrasonic or thermal
installation of inserts. Thermoset compounds, however,
are often brittle and less resilient than thermoplastics.
They respond better to molding or post-molding cold insertion.
threaded inserts for plastic come in a variety of styles and sizes
to meet a variety of applications. They are
following thread specifications: UNC-2B and UNF-2B
for inch threads
and ISO-6H for metric threads.
these links for more information about threaded inserts
for plastics: Insert Installation
Methods | Design
Guidelines | Tri-Star
Threaded Insert Selection Guide