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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: richard5933 on December 14, 2020, 05:04:07 PM
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Is there a standard torque for tightening a constant tension clamp? Or is it just till it stops leaking and then another little bit? Hard to do it by feel, since the clamps always feel a bit softer than a normal hose clamp to me.
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Not sure of the answer to your question but the link pertaining to your question is interesting:
https://www.jcshi-torque.co.uk/constant-tension-hose-clamps-effective/
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Tighten it till spring has a good tension but do not collapse the spring ,you need to tighten those a few times to get the right tension anyways I really don't care for those I use the lined clamps with better results
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I have never used constant tension clamps on liquid hoses but have had good experience with them on exhaust band clamps.
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Richard here is a link to the McMaster-Carr page with constant torque clamps. The page list the max torque for different sizes.
I have been converting over to these clamps. I have had to tighten them a few times over time to get them to there sweet spot. After that just spot checking them a few times a year.
https://www.mcmaster.com/constant-torque-hose-clamps/
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Those are the clamps I bought...guess I didn't dig far enough through the links, as I just found that they have a max torque of 90 in. lbs which is about 7.5 ft. lbs.
Over the past few years I've had a few places that dripped in the winter. They had regular hose clamps on them, and I was able to stop the drips with by tightening slightly. This year, it seems that I have more than a few. The worst were on the two rubber couplings along the 1" line which feeds the heater core.
I did finally get them all tight enough to stop the leaks, but it certainly took more turns on the clamps than I expected. In the past it only took 1/4 turn or so, this time it was over a complete turn.
My concern is that there are only so many times this can be done before the rubber is fully compressed and loses the ability to absorb any further expansion/contraction from temperature variations. I've got replacement couplings on hand, and I'm thinking that in spring I'll replace them so I can have more rubber between the pipe and the clamp once again. I guess that these are OEM rubber, so they've given more than anyone can expect from them.