TPi March 2016

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84 Tube Products International March 2016
Fine Tubes Ltd – UK
Superior Tube Company – USA
to avoid contamination in the metal. In the case of small
diameter tubing, the cleaning process needs to be that
much more robust. Both Superior Tube and Fine Tubes use
an immersion de-greasing process as well as a secondary
cleaning operation for all small diameter products.
What materials are used?
Tubing manufactured by Superior Tube and Fine Tubes is
essentially made to order for customers who specify not just
the size but also the material to be used, as well as other
special requirements. However, there are occasions when
customers seek advice in relation to specific applications.
Typically, both companies manufacture small diameter tubing
in 300 series austenitic stainless steel, a range of high-
temperature nickel alloys, and certain grades of both titanium
and zirconium.
How are they tested?
The background to all testing procedures is the quality
system that underlies them. Both companies hold ISO
9001 certifications as well as a wide range of industry
and specific customer approvals. These certifications and
approvals are supported by extensive in-house capabilities for
metallographic testing, mechanical testing, non-destructive
testing, some destructive testing, and visual and dimensional
inspection.
An important point to make is that when testing small
diameter or thin wall tubes, commonly used methods such as
the Rockwell test are not ideal, as the relatively high load can
distort surfaces or even punch holes through the tube walls.
The critical need is to find a way of effectively correlating
the results from different testing methodologies. Fine Tubes
has undertaken detailed research with the UK National
Physics Laboratory to find a meaningful comparison between
hardness scales using different tests.
A heritage of small diameter tubing
Superior Tube was founded in 1934, and Fine Tubes in 1943.
Between them, the two companies have a long record of
producing high-performance tubing, including small diameter
tubing, for the most demanding applications presented to
them by their customers.
Superior Tube took advantage of the 1939 New York World’s
Fair to demonstrate that it had the capability to meet
technological demands beyond those its customers yet
required. On display was “the smallest tube ever made” – a
tube with a total diameter of just 26/10,000th of an inch. While
it was manufactured purely for the sake of the exhibition,
to demonstrate that it was possible, it has been claimed
that tubes of this scale have been used for the artificial
insemination of mosquitoes!
Building on their heritages, both businesses are now part of
Ametek Specialty Metal Products, a division of Ametek, Inc,
and are positioned as market leaders in small diameter tubing
for applications that require extremely tight tolerances, special
mechanical properties or unusual alloys. Superior Tube and
Fine Tubes pride themselves on being able to produce such
exclusive products.
Hypoflex needle tubing
Specialist tubing for cardiac stents