Heat Pipes
In the early days of space flight, NASA solved a major problem
by teaming with Los Alamos Scientific Laboratory (LASL) in development
of the heat pipe. The problem was that the Sun-facing surfaces
of a non-rotating satellite became very hot while surfaces not
exposed to the Sun became extremely cold, a temperature differential
that threatened failure of electronic systems. The solution,
used in virtually all spacecraft since its development, was the
heat pipe, a tubular device in which a working fluid alternately
evaporates and condenses, transferring heat from one region of
the tube to another without external help.
Hot runner nozzles provide the consistent temperatures needed
to make uniform parts.
This simple device offered a very broad range of practical
Earth applications and NASA prompted its broadest use by refining
the technology and working with a number of other organizations
on technology demonstrations. Heat pipe technology has become
one of the most frequently tapped sources of spinoff applications.
Some of the early users have further advanced the technology
and broadened the range of applications through several generations
of product development.
Among the latter is KONA Corporation, Gloucester, Massachusetts,
a company formed in 1978 to manufacture hot runner systems for
the plastics injection molding industry, using heat pipe technology
that offered significant manufacturing and maintenance economies.
KONA operated initially under a license from James M. Stewart,
an independent consultant to the plastic industry, who had used
the NASA/LASL technology as a departure point for his own development
of patented "heat tubes."
KONA has continued to use the NASA technology as an integral part of its
manufacturing equipment for such products as camera parts, kitchenware,
auto components, TV cabinets and telephone parts. KONA has refined the
technology through three generations of heat pipe advancement. The first
was the KONA Nozzle, a heaterless injection nozzle designed to fit all
injection molding systems; it was followed by a complete line of Hot Sprue
Bushings. KONA also applies heat pipe technology to the company's Hot Runner
Systems.
Hot runner systems are used for production of a wide range
of plastic products, from ice trays to medical devices.
Temperature uniformity is critical in hot runner molding and
the heat pipe, KONA says, is a way of getting it with multiple
advantages over alternative systems. By offering a wide selection
of hot runner nozzles and tips, KONA gives mold designers and
moldmakers exceptional flexibility. KONA Hot Runner Systems are
used throughout the plastics industry in the manufacture of products
ranging in size from tiny medical devices to large single cavity
auto bumpers and instrument panels. Sales of Hot Runner Systems
account for 75 percent of all KONA sales.
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