clamps. This silicone hose is quite soft so a SS liner is
needed in
the
hose
clamp to prevent the hose from extruding through the worm gear
slots.
The constant torque feature means the clamp can expand and
contract
slightly as the aluminum hose barb expands and contracts when
it warms up and cools down. The washers are actually
Belleville
springs
back to back. The Breeze part number is CT-200L.
McMaster Carr part #5281K-17. I bought a box of ten for about
$34.
Al Gietzen wrote:
Just a suggestion - if you're clamping so tight as to extrude
the
silicon
through the slots; you are likely clamping too tight. Over
tightening
damages the hose and can result in premature failure. Using
double
clamps,
or wider band clamps (like 5/8" wide, or more) to spread the
clamping
force
over a larger area is a good idea.
It is important that the tube your are connecting to at both
ends
cannot
move apart. With 25 psi pressure, on a 1-1/2 line, there is
about a
45
lb
force trying to push things apart.
Al
That silicone is REAL soft Al. Get some and try it?
The clamps I recommend above are 5/8" wide.
Good point on the separating force. 30 PSI is 53 pounds.
Interestingly enough .140 dia spring steel wire clamps are
universally
used
in automotive applications these days. In theory they are ideal
as
they
too expand and contract with barb temp changes. The downside is
the
narrow bearing area on the hose. I don't think they would work
with
silicone
hose.
Paul Lamar
Yellow Freight (for whom I do tractor-trailer maintenance) insists
that
ONLY
silicone hose clamps are to be used on silicone hose. The
exterior of
the
hose is so soft, that the hose squeezes up through the slots of a
standard
worm gear clamp when tightened with even a small screwdriver, let
alone
after they are properly torqued. I would not even consider using
standard
worm gear hose clamps on silicone hose. Just another opinion based
on
experience. Paul Conner, Mobile, AL
Does that mean the hose clamp is made from silicone Paul ? :)
Got any brand names or part numbers on those silicone hose clamps?
Paul Lamar
Hi, Paul....of course the clamps are not made of silicone, as you
know, and
quickly seized the opportunity to pull my leg....I use the Breeze part
number 9216 and 9220 for the 5/8" silicone heater hose, and larger
constant
torque clamps for the radiator hose, which I purchase from Truck Pro.
Click
on www.westernlinksales.com/products/hoseclamp.htm# and then click
on "
Liner clamps for soft silicone hose" and you will see the listings for
various Breeze silicone hose clamps. Hope this helps. Paul Conner
Thanks Paul
Paul Lamar
OK those are basically the same as the one I bought. Both have liners to
protect
the silicone hose. In addition the one I bought has constant torque that
compensates
for expansion and contraction of the aluminum hose barbs. Those are
probably a bit cheaper.
This may seem like we are beating a dead horse but details like this are
extremely
important.
Paul Lamar
***************************************************************************
Breeze liner clamps seal soft hose without damage.
There are four important things about silicone hose which have a direct
effect on clamp selection; silicone hose is soft, hard to seal, expensive,
and
durable. Breeze liner clamps were developed to offset the first three and
to compliment the durability. They afford maximum protection to silicone
and
other soft hoses while providing a true concentric seal.
To protect the hose from extrusion and shear, we extend an inner liner to
cover the worm-gear slots. These inner liners are integral
extensions of the band, not separate welded or riveted extensions that
won't lie true to the clamping axis. There are no bumps under the
housing to jeopardize the concentricity of the seal, and no laminated
coverings to disintegrate under heat, ultraviolet, chemical or corrosive
attacks.
Additionally, Breeze liner clamps are available with extra wide bands -
1/2", 9/16" or 5/8" - to spread sealing pressure over the widest
possible area. They come in 100% stainless steel - important because
silicone hose can last up to 10 years or more, and clamps that are
not stainless can rust out in less than 2 years. Breeze Aero-Seal liner
clamps are designed with Quadra-Lock construction which enables more
tightening torque to be delivered to the perforations while maximizing
vibration resistance.
Available in both 9/16" (14 mm) and 1/2" (13 mm) band width. For
1/2"(13 mm) wide part numbers, add H to the size required. E.G. 9206H
Breeze liner clamps protect your investment in silicone hose -- insure
that you get the durability you're paying
for.
*************************************************************************
Paul
As a Licensed Aircraft Engineer I shudder at this very critical
airworthiness issue. My experience in experimental aviation has seen these
areas of fasteners, and quality of fittings etc overlooked - or at best
ignored. Certainly if it was my butt strapped into a single engined
aircraft, presumably with loved ones aboard, I would be going with the
maximum quality - hang the expense. AN fittings are the best, and rarely do
they fail. I support you in moving away from simple hose clamps on flexible
hose joints, but I still would like a threaded fitting that can be
positively torqued. I use two clamps at each joint on my drag car as a
precaution, but that only runs for minutes at best. In the air I would
consider parts that a Regulator would pass for certification. maybe I am
conservative, but airworthiness is just that - staying in the air.
Regards PC
Paul Carey LAME, MC
Aero Management - aviation consultants.
www.aeromanagement.com.au
(08) 9371 5205 0418 959 892-