Perforated Stainless Hose Clamps

[PaulGel]

I am convinced boats are held together by hose clamps and zip ties. I started in the bilge and I have been changing all the hose clamps (and a lot of the hoses) on our boat from perforated to stamped. They were all stainless steel of various quality but I have so far found five that had failed across the webbing. Two fell off when I touched them. All the failed ones showed signs of corrosion and the failures were sometimes out in the open and sometimes under the screw thread.

Here is an example:



I didn’t start collecting them until I was someway through the process but here is my collection to date:



The experts are right when they say these things have no place on a boat.

 

[Comodave]

Yes the perforated ones will break. I prefer AWAB brand, rolled edge and non perforated.

 

[GFC]

Being the non-mekanyik sort of guy that I am, and being familiar with only the type of clamp shown in the photos above, what else is there? Help this poor, stoopid guy out, will ya?

 

[Comodave]

I like AWAB clamps. They are more expensive but they are 316 S/S. They are a bit cheaper if you buy them by the box. Just google AWAB hose clamps

 

[Lou_tribal]

I am using this kind of clamp

Only thing is that you have to lnow the external diameter of your hose as the range to tight them is shorter.

L

 

[ghost]

I would generally agree and personally purchase awab clamps as well. Well worth the cost.

But to be a bit contrarian, I lived through decades without any near misses on the old style worm clamps and even today, few stores have the nicer clamps on stock. When that happens, it’s not a blocker for me. The condition of the clamps you are removing is much worse than what you should see, even with that clamp style. First, those clamps should be inspected whenever they are reused, no way they got in that condition consistently if inspected each time. Second, those clamps were severely over tightened and that’s not the clamps fault. An swab will take more abuse, but that does not justify, nor solve the issue with how they were installed. You should tighten clamps to a good tension, then come back after they have taken a set and snug them up later without over torquing them. A broken worm is an installers fault, not a mfg defect. Over tensioned clamps that bend and show signs of Sticking have already failed and should be discarded immediately instead of just tightened with a bigger screwdriver.

We always had to watch for the non stainless screw, but even if you did get one, they should last a long time and get caught in an annual inspection .

Practice good clamp hygiene and you should easily get by without an entire boat of expensive clamps. It’s a luxury, not a necessity. JMHO because somebody might think that upgrading their clamps solves installer failures and that’s not really an optimized solution.

 

[O C Diver]

Not all perforated clamps are equal.
On some models, the area to either side of the perforation can be significantly wider (making the whole clamp significantly wider. These can obviously have a great deal more strength.

While I do like the non perforated clamps, there are junky ones of those also. Most commonly they lose the edge on the screw threads and release tension.

On the highly critical stuff I prefer the T bolt clamps, but they are pricey.

As we now live in the era of Chinese junk and knockoffs, I inspect all clamps before installing.

Ted

 

[Bacchus]

Being the non-mekanyik sort of guy that I am, and being familiar with only the type of clamp shown in the photos above, what else is there? Help this poor, stoopid guy out, will ya?

Mike
CMS - a commercial member here on TF provides some excellent info & articles - here's his article on hose clamps...

https://marinehowto.com/proper-installation-of-double-hose-clamps/

 

[koliver]

Being the non-mekanyik sort of guy that I am, and being familiar with only the type of clamp shown in the photos above, what else is there? Help this poor, stoopid guy out, will ya?

Hey Mike. Not stoopid, at least I am with you if you are. I avoid the ones that are stamped "All Stainless" and have a zinc plated screw that lasts one year.
Otherwise mine are mostly the worm screw kind.
There are T type clamps on the hose to exhaust elbow connection, but I don't recall any other Ts on my boat.

 

[GFC]

Who says old guys can't be edjumicated! I've used those AWAB clamps in the past and didn't even realize I was doing something right. Whoodathunk.

 

[PaulGel]

Even T Bolt clamps shouldn’t be the spot welded ones because they corrode and fail around the weld, that’s why I don’t use them, plus on a lot of fittings you can’t get two on because of their width. I use the spring ones on heat affected hoses on the engine to retain the tension.

I have been thinking of what to do with all the clamps I have removed and I reckon the poster who is most in denial can have them as long as they promise to use them on all their sea cocks.

 

[menzies]

They are stain-less.

Not stain proof.

 

[kchace]

I have been thinking of what to do with all the clamps I have removed and I reckon the poster who is most in denial can have them as long as they promise to use them on all their sea cocks.

That's an awesome idea!

Like you I went through my entire boat and replaced almost all clamps with Awab. I found only a few truly questionable clamps, but what I did find that was pretty bad was EVERY near or below waterline connection had been double clamped (obviously after the fact since the clamps were different) including many places where double clamps did not fit over the hose barb! This is a major problem because not only does this not increase the security, but the clamp can actually damage the hose and help it to creep off the hose barb.

Ken

 

[Simi 60]

On the highly critical stuff I prefer the T bolt clamps, but they are pricey.

As we now live in the era of Chinese junk and knockoffs, I inspect all clamps before installing.

Ted

I have had "Trident" T bolt clamps break at the 3 small spotwelds.

I have replaced with cheap Chinese T bolt copies as they appeared same same but had 4 spots where Trident had 3.

Working on the principle that because they are cheaper I can carry plenty of spares

 

[Bkay]

I've used those AWAB clamps in the past and didn't even realize I was doing something right. Whoodathunk.

There's an old saying in Special Forces - Sometimes it's better to be lucky than good.

 

[PaulGel]

Apparently you can get T Bolts with folded hooks rather than spot welds and that solves the problem but I have never managed to source them. If anyone has a brand I would appreciate the info. Thanks

 

[Comodave]

Steve D has referred to them but I haven’t seen them for sale either.

 

[Action]

There are different grades of stainless.
https://blog.mchoneind.com/blog/stainless-steel-grades-chart


I suspect the failed "all stainless" clamps are 303.

 

[Simi 60]

I have had "Trident" T bolt clamps break at the 3 small spotwelds.

Had another tridon fail on me today.
Bloody expensive clamps to fail like this.

 

[tpbrady]

I had an AWAB hose clamp just fail on raw water hose. It started leaking and couldn't be tightened or loosened. The screw had basically seized. Went to NAPA in Ketchikan and they sold me a T-bolt clamp with 4 bent tabs per side. The brand is NORMA and this specific model is ND57 W5. Nice clamp but expensive.

 

[Simi 60]

https://www.normagroup.com/corp/en/products/norma-gbs/

 

[tpbrady]

Simi,

That's the one.

Tom

 

[diver dave]

I had an AWAB hose clamp just fail on raw water hose. It started leaking and couldn't be tightened or loosened. The screw had basically seized. .

Inspect the new ones carefully. They should have a shot of lube grease at the screw interface.

 

[Steve]

Several posts mention expensive clamps failing at welds etc. what sort of warranty if any are they covered by? Seems lots of items now have "lifetime" Warranty.

 

[NewbieFromNJ]

Isn't also true to double clamp (regardless of clamp style) when practical?

 

[Comodave]

Yes, if there is enough room on the hose barb for 2 clamps. If there isn’t enough room on the barb then putting 2 clamps on can be a bad thing and actually harm the hose.

 

[peteney]

Anyone have experience with Scandvik ABA 316 Hose Clamp?

 

[Comodave]

They are pretty comparable to AWAB as far as I can tell, just a different manufacturer.

 

[Steve DAntonio]

Being the non-mekanyik sort of guy that I am, and being familiar with only the type of clamp shown in the photos above, what else is there? Help this poor, stoopid guy out, will ya?

Mike:

This two part article describes the options in detail...

Part I: https://stevedmarineconsulting.com/hose-clamps-part-i-design-and-selection/

Part II: https://stevedmarineconsulting.com/hose-clamps-part-ii-installation-and-use/

Solid, embossed hose clamps are preferred, however, lots of high end builders, along with engine manufacturers, continue to use the perforated automotive style clamps, they work but are not nearly as robust or long-lasting. While I don't recommend wholesale replacement of seemingly sound perforated clamps, if the screw is magnetic, they should definitely be replaced.

 

[Simi 60]

Several posts mention expensive clamps failing at welds etc. what sort of warranty if any are they covered by? Seems lots of items now have "lifetime" Warranty.

Tridon make no mention of warranty on their website that I found, though I do see mention of 60 days warranty on resellers sites.