Hose clip failure

  • Thread starter Thread starter TQA
  • Start date Start date
TQA

TQA

Well-Known Member
Joined
20 Feb 2005
Messages
6,815
Location
Carribbean currently Grenada
sailingonelephantschild.blogspot.com
11 Years ago my boat was the subject of a no expense spared major refit. All hoses and hose clips were replaced. A substantial supply of spare clips formed part of the inventory when I bought her.

In the past 5 years 1 to 3 clips have failed each year. Not because they were over tightened or seized they just broke in silence and secretly.

This morning I came across another.

So all clips and most hoses are getting replaced.

Does anyone have a particular make or type of clip that is to be recommended.

If you have any hose clips of the type MURRAY made in the USA I would replace them with another make.

2-IMG_0289.JPG 3-IMG_0290.JPG 4-IMG_0296.JPG
 
TQA said:
11 Years ago my boat was the subject of a no expense spared major refit. All hoses and hose clips were replaced. A substantial supply of spare clips formed part of the inventory when I bought her.

In the past 5 years 1 to 3 clips have failed each year. Not because they were over tightened or seized they just broke in silence and secretly.

This morning I came across another.

So all clips and most hoses are getting replaced.

Does anyone have a particular make or type of clip that is to be recommended.

If you have any hose clips of the type MURRAY made in the USA I would replace them with another make.

View attachment 78829 View attachment 78830 View attachment 78831
Click to expand...

Scandvik/ ABA non perforated 316 stainless.
 
That clip looks as if it's been pretty wet for the last 11 years?
And probably never seen any lubricant?

These things mostly need to be checked before they get anything like that bad.
I was looking at the clips on a mate's cockpit drain hoses the other day, almost completely inaccessible, nearly ended up buying a selfie stick to look at them with a mobile phone camera.
 
langstonelayabout said:
Silly question time: Does a jubilee clip that has been fitted actually need any lubrication during it's life? I assume the reason for failure is crevice corrosion?
Click to expand...

That failure looks like rusting of a mild steel helix. Probably aggravated by elecrolysis due to the stainless it's in contact with.
A bit of lube might have avoided wearing all the plating off the helix and kept the water out.
Of course you don't want to slather on lots of oil or grease which will attack rubber hoses.
A squirt of something suitable when you check things regularly might help?
People do check over their boat from time to time?
On a boat I'd use an all-stainless clip if possible but cheap clips often seem to survive for many years.
 
We have started fitting stainless t bar clamps as they don’t have the worm drive and slots that seem to be area of failure, only downside is that they have limited adjustment range so you need to choose size carefully
 
I am using X2 SS "T" bar hose clamps below the WL and on the motor but elsewhere I am using SS worm drive clamps.
 
Any full stainless ones that aren't perforated. Yours had a galvanized or electroplated screw and were perforated - the worst kind. I replaced original ones with rusty screws all over my boat (none had failed yet, but several had to be cut off). Below waterline or otherwise critical stuff is double-clamped.

Lots of brands available, just look for the above criteria. Mikalor from inox.ie are definitely good: http://www.inox.ie/acatalog/HoseClamps.html
 
Yngmar said:
Any full stainless ones that aren't perforated. Yours had a galvanized or electroplated screw and were perforated - the worst kind. I replaced original ones with rusty screws all over my boat (none had failed yet, but several had to be cut off). Below waterline or otherwise critical stuff is double-clamped.
Click to expand...

I bought some non-critical SS worm type hose clips from a Chinese eBay seller (with a high rating) and when I got them I realized the worm gear was slightly magnetic and therefore was not SS (We all know that don't we?)

I started of the complaint procedure and demanded my money back and made some discourteous remarks to the seller. He was bewildered because, he said, no one else had complained. He went back to the very large manufacturer in China of ss products and they assured him that the clamp was all SS.
Apparently:
Wrought, austenitic stainless steels, such as 304 and 316, are generally regarded as non-magnetic in the annealed condition, ie they are not attracted significantly by a magnet. However, if they are cold worked they will be attracted to a permanent magnet. (Assd. asn)
 
Last edited:
coopec said:
I bought some non-critical SS worm type hose clips from a Chinese eBay seller (with a high rating) and when I got them I realized the worm gear was slightly magnetic and therefore was not SS (We all know that don't we?)

I started of the complaint procedure and demanded my money back and made some discourteous remarks to the seller. He was bewildered because, he said, no one else had complained. He went back to the very large manufacturer in China of ss products and they assured him that the clamp was all SS.
Apparently:
Wrought, austenitic stainless steels, such as 304 and 316, are generally regarded as non-magnetic in the annealed condition, ie they are not attracted significantly by a magnet. However, if they are cold worked they will be attracted to a permanent magnet. (Assd. asn)
Click to expand...

Stainless knives are commonly magnetic.
 
The worm screw of a hose clip would seem to be the ideal candidate for manufacture by cold stamping. This cold work process is sufficient to induce some magnetism.

Knife blades are made from ferritic 400 series SS.
 
> Stainless knives are commonly magnetic.

Stainless steel is not magnetic which implies the knives are not made of that. Stainless products a have a higher chromium content and nickel is also added. It is the nickel which modifies the physical structure of the steel and makes it non-magnetic.
 
KellysEye said:
> Stainless knives are commonly magnetic.

Stainless steel is not magnetic which implies the knives are not made of that. Stainless products a have a higher chromium content and nickel is also added. It is the nickel which modifies the physical structure of the steel and makes it non-magnetic.
Click to expand...

Although knives and kitchen sinks are both made of stainless steel, they're made of different combinations of alloys so they have different magnetic properties.
https://www.abc.net.au/science/articles/2009/11/19/2746568.htm

Kitchen sinks are made of stainless steel and they are magnetic.
 
KellysEye said:
> Stainless knives are commonly magnetic.

Stainless steel is not magnetic which implies the knives are not made of that. Stainless products a have a higher chromium content and nickel is also added. It is the nickel which modifies the physical structure of the steel and makes it non-magnetic.
Click to expand...

"A little knowledge is a dangerous thing"
 
KellysEye said:
> Stainless knives are commonly magnetic.

Stainless steel is not magnetic which implies the knives are not made of that. Stainless products a have a higher chromium content and nickel is also added. It is the nickel which modifies the physical structure of the steel and makes it non-magnetic.
Click to expand...

This post contains the faintest glimmer of truth but if you would like to know how wrong you are I can recommend some reading. It's a book called Metals in Boats, by a metallurgist named Vyv Cox.
 
vyv_cox said:
This post contains the faintest glimmer of truth but if you would like to know how wrong you are I can recommend some reading. It's a book called Metals in Boats, by a metallurgist named Vyv Cox.
Click to expand...
Not to detract from your own work, which I admit I haven't read, nor the point you make, but I also enjoyed Nigel Warren's Metal Corrosion in Boats.
 
Yngmar said:
Any full stainless ones that aren't perforated. Yours had a galvanized or electroplated screw and were perforated - the worst kind. I replaced original ones with rusty screws all over my boat (none had failed yet, but several had to be cut off). Below waterline or otherwise critical stuff is double-clamped.

Lots of brands available, just look for the above criteria. Mikalor from inox.ie are definitely good: http://www.inox.ie/acatalog/HoseClamps.html
Click to expand...

Thanks for that Yngmar. Good prices too.
 
You must log in or register to reply here.

Share this page

Top