Better hose clamps?

jrd22 · #1 (**permalink**) 10-01-2009

We just had a Mayday near home, it was a whale watching boat with 28 people on board and it was taking on water faster than the bilge pumps could handle. Everything turned out OK, no injuries and they saved the boat with additional pumps. It was a hose clamp failure on the shaft bellows. The owner/captain said that he had changed out almost all of the hose clamps to the new non-perforated ABA approved style but the two that failed (one broke, the other was either in the wrong place or not tight enough to stop the water, not sure which) had been overlooked for replacement. I too bought a bunch of the ABA approved type intending to use only those when we did our refit, but I have quit using them because of the frequency of them stripping out as I tighten them. I have not checked if there are recommended torque settings for them, but if I tighten them like I do the perforated ones they almost invariably strip. I have talked to a couple of guys at boat yards and they say they have had the same experience. Anyone else have the same problem with the ABA approved clamps? Mine are all in a separate box now as spares.

smackdaddy · #2 (**permalink**) 10-01-2009

jrd - so the ones that broke were the perf ones? Do you happen to know if it was the band (corroded) or the screw/housing that failed? I just redid our head plumbing and used the perf ones. When I pulled off the old ones the screw/housing on each was in really bad shape.

Holy crap - I just posed in G&M. Sorry fellas - I don't know what I was thinking.

jrd22 · #3 (**permalink**) 10-01-2009

The one on the whale watching boat that broke was an old perforated type. My concern is that all of the "new improved" type (non perforated) seem to strip out at a much lower compression point than the perforated ones. Which means that if you don't tighten them down for fear of stripping them hoses are not as secure on thru hulls etc. I've tried at least two different brands with the same poor result.

preservedkillick · #4 (**permalink**) 10-01-2009

This summer I was able to tour a local Coast Guard station including the big rescue boats. What awesome machines! The engines were huge, and spotlessly clean (whatever they were I don't know). I did note however that all hose clamps on the two engines were the perforated type, and nothing special. it just looked like they were replaced frequently.

For what it is worth.

Maine Sail · #5 (**permalink**) 10-01-2009

Quote:

Originally Posted by jrd22

I too bought a bunch of the ABA approved type intending to use only those when we did our refit, but I have quit using them because of the frequency of them stripping out as I tighten them. I have not checked if there are recommended torque settings for them, but if I tighten them like I do the perforated ones they almost invariably strip. I have talked to a couple of guys at boat yards and they say they have had the same experience. Anyone else have the same problem with the ABA approved clamps? Mine are all in a separate box now as spares.

Are they AWAB brand? I have been using AWAB (brand name) for about 8+ years and have never had even one strip out.

What brand of non-perf clamps are you using? Could it be a bad batch? The AWAB's are considerably more rugged than the Ideal clamps..

casioqv · #6 (**permalink**) 10-01-2009

I like to use dual T-bolt hose clamps made from solid 316 marine grade stainless on every fitting. The two T-bolts are oriented on opposite sides from one another.

They should also never be overtigtened and replaced every 10 years to reduce chances of failure from chloride stress corrosion cracking, or crevice corrosion.

Stainless hose clamps are under tension, and will eventually fail from chloride stress corrosion cracking.

Omatako · #7 (**permalink**) 10-01-2009

The t-bolt type clamps are great where they fit but they're a little more robust than most applications require. They also take up a lot of space and often hose tails are not long enough or there simply isn't space. I guess overkill never did any real harm but they're a bit heavy for me. I use these on large diameter pipes like exhausts and cockpit drains.

For hoses like water intakes for heads, galley and shower drians, engine piping and so on I use the perforated type simply because they don't strip easily. So they cut into the hose a little, doesn't bother me. I think it's easier to see a perf clamp that is likely to fail due to corrosion than a non-perf one that's about to strip.

Obviously they should be used in pairs, tightened with a spanner, not a screwdriver and should be regularly checked. I've had a few break over the years but they have never caused me any special problems being that they are in pairs.

kd3pc · #8 (**permalink**) 10-01-2009

been using AWAB all stainless for many years with no failures to report. I have bought them from suppliers in quantity to keep the cost down. Well worth the added cost, IMHO. They need to be "sized" correctly and tightened correctly for maximum effect.

Auto "stainless" are junk, not worth the effort to use them.

Stillraining · #9 (**permalink**) 10-01-2009

I use one of these where I can.

T-Handle Torque Wrenches

jrd22 · #10 (**permalink**) 10-01-2009

Maine- I have tried two brands, one was Ideal and not sure about the other. They were both 316 SS. I'll have to try and find the ones you mentioned, but I'm concerned that people are using these "approved" clamps and they may be potentially dangerous if they strip out as easily as it seems. I think the worst ones were bought at WM.