4, 1998 Design News
BREAKTIME The lighter side of engineering
Bad fasteners can sink ships
by Julie Anne Schofield, Senior Editor
Bad acting and sappy dialogue didn't stop Titanic from
winning the best picture Oscar. But bad rivets might
have stopped the actual ship from surviving its brush
with an iceberg.
According to Timothy Foecke, a metallurgist with the
National Institute of Standards and Technology, substandard
fasteners may have been what really sank the Titanic.
He examined two rivets recovered from the ship's hull
and found them to contain high concentrations of slag--a
residue left by the smelting process which made the
fasteners dangerously brittle.
Millions of rivets held together the steel beams and
plates of the 46,000-ton ship. Forensic specialists
studying the disaster say the brittle rivets may have
popped, causing the plates to separate and let in the
This conclusion squares with the findings of shipwreck
investigators who used underwater sonar to study the
Titanic about a year ago. Dispelling the theory that
an iceberg slashed a 300-ft gash in the ship's hull,
they say it was the force of the impact that caused
the riveted seams of the hull to pop open.
No one's saying that stronger rivets would have definitely
prevented Titanic from sinking, but they very well may
have bought the hundreds of passengers who didn't fit
in the lifeboats another hour or two. Perhaps enough
time for a nearby ship to rescue them.
Fasteners aren't glamorous, but they're absolutely
necessary for good product design. A digital cellular
phone with so many features you can't possibly learn
them all isn't terribly useful if it comes apart under
heavy use. A $5,000 laptop computer doesn't seem like
such a marvel anymore if the latches for opening it
don't work perfectly. And when I'm driving a car, the
thing that annoys me most is hearing a rattle that just
won't go away.
At Design News, each editor specializes in
one or more areas of technology--their beats. I handle
semiconductors and CAD--pretty sexy stuff. Associate
Editor Deana Colucci covers fasteners and adhesives--the
screw-it-or-glue-it beat. Not usually the stuff of cover
But fasteners hold their own. For example, each December
we ask readers to pick the best product of the year,
and the fastening product is always among the top finishers.
This year, the PEMr R'ANGLE self-clinching fastener
from Penn Engineering and Mfg. Corp. was a strong contender.
Last year, Southco's SentinelTM ratchet-action
captive screw drew lots of votes.
And in 1996, the Ultra-Lok bolt from Ultra-Lok Fasteners
took the top prize as Design News product of
the year. The self-tapping Ultra-Lok repairs stripped
or damaged threads by cutting new threads as you install
it. The metal shavings created pack into a reservoir,
locking the bolt in place and forming a vibration damper.
These companies sweat the details. Their livelihoods
depend on getting the little things right.
So, pay attention when you spec a fastener. You decision
can make or break anything from a $5 calculator to a
multimillion-dollar TransAtlantic ship.
Please comment on this or any other topic
by sending e-mail to firstname.lastname@example.org.
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Selected from Fundamentals of Engineering
Examination, copyright 1986, Eugene L. Boronow, N.E.E.,
P.E., Simon & Schuster, Inc., NY. Reprinted with
permission of the publisher.