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svHyLyte · 03-12-2007, 08:28

We are very diligent about house-keeping and maintenance on our yacht in order to ensure that things work when needed. Accordingly, I was very surprised this past weekend when I discovered that one of the supposedly Stainless Steel hose clamps on the raw-water intake side of our forward head had broken and slipped down the hose (which I found while doing the weekly "thorough" cleaning of the area behind the head with a bucket of hot soapy water.)

Upon inspection I discovered that rust had developed under the screw clamp, which was out of easy sight on the bottom side of the hose, until enough had built up to generate sufficient pressure to rupture the perforated strap around the hose. Further inspection revealed that all of the hose clamps on this installation--which is less than 18 months old--were showing similar deterioration and rust build-up.

These Stainless hose clamps--ranging from 3/4's to 2 inches in diameter--were purchased a West Marine and were not inexpensive. Further inspection revealed that, in each case, the rust seemed to emanate from the point where the ends of the perforated straps where spot welded to the under-side of the screw assembly. Evidently, this spot welding process changes the properties of the material enough to allow rust to develop. Rust--or iron oxide--reportedly has a volume approximately 600% of the volume of the iron consumed as rust is formed. Hence-its formation under the strap can build-up sufficient pressure to rupture the strap. (Inspection of several new-unused clamps--in the spares box revealed that all had the beginnings of rust in the same location and all bore the inscription "Made in China".)

We are now going through the yacht and replacing any hose clamps that show similar deterioration and which, when found, also seem to be relatively recent replacements. Interestingly, the hose clamps that are in the best condition are the original 1985 era stainless steel clamps used by Beneteau when the yacht was constructed. These have no welds at all. The screw assembly's are held in place with small clips that fit into slots cut into the edges of the straps. The nice thing about these is that the straps can be threaded into the screw assembly's and then--once the strap is passed around the hose--the strap ends popped into place on the ends of the screw assembly's with one hand.

I do not know if this problem is isolated to West Marine's supplies so this should not be considered an indictment of that Company. I do know, however, that at several dollars each, these items should not fail in this manner--regardless of the supplier--and that doing so could be catastrophic. If I can track down a source for the original, unwelded type, straps I shall post the source and I will appreciate a referral is anyone already knows of a source.

s/v HyLyte

03-12-2007, 08:28	#1
svHyLyte Registered User Join Date: Mar 2006 Location: Tampa Bay area, USA Boat: Beneteau First 42 Posts: 990	Check Your "Made in China" Hose Clamps! We are very diligent about house-keeping and maintenance on our yacht in order to ensure that things work when needed. Accordingly, I was very surprised this past weekend when I discovered that one of the supposedly Stainless Steel hose clamps on the raw-water intake side of our forward head had broken and slipped down the hose (which I found while doing the weekly "thorough" cleaning of the area behind the head with a bucket of hot soapy water.) Upon inspection I discovered that rust had developed under the screw clamp, which was out of easy sight on the bottom side of the hose, until enough had built up to generate sufficient pressure to rupture the perforated strap around the hose. Further inspection revealed that all of the hose clamps on this installation--which is less than 18 months old--were showing similar deterioration and rust build-up. These Stainless hose clamps--ranging from 3/4's to 2 inches in diameter--were purchased a West Marine and were not inexpensive. Further inspection revealed that, in each case, the rust seemed to emanate from the point where the ends of the perforated straps where spot welded to the under-side of the screw assembly. Evidently, this spot welding process changes the properties of the material enough to allow rust to develop. Rust--or iron oxide--reportedly has a volume approximately 600% of the volume of the iron consumed as rust is formed. Hence-its formation under the strap can build-up sufficient pressure to rupture the strap. (Inspection of several new-unused clamps--in the spares box revealed that all had the beginnings of rust in the same location and all bore the inscription "Made in China".) We are now going through the yacht and replacing any hose clamps that show similar deterioration and which, when found, also seem to be relatively recent replacements. Interestingly, the hose clamps that are in the best condition are the original 1985 era stainless steel clamps used by Beneteau when the yacht was constructed. These have no welds at all. The screw assembly's are held in place with small clips that fit into slots cut into the edges of the straps. The nice thing about these is that the straps can be threaded into the screw assembly's and then--once the strap is passed around the hose--the strap ends popped into place on the ends of the screw assembly's with one hand. I do not know if this problem is isolated to West Marine's supplies so this should not be considered an indictment of that Company. I do know, however, that at several dollars each, these items should not fail in this manner--regardless of the supplier--and that doing so could be catastrophic. If I can track down a source for the original, unwelded type, straps I shall post the source and I will appreciate a referral is anyone already knows of a source. s/v HyLyte __________________ "It is not so much for its beauty that the sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."