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BIGLICKER
15-12-2010, 20:59
When is a brand new cylinder due for its test? And, what test does it need???
Anyone know?


thanks

r O y.:eek:
John_C
15-12-2010, 21:09
When is a brand new cylinder due for its test? And, what test does it need???
Anyone know?


thanks

r O y.:eek:

2.5yrs after date of manufacture = visual
5 yrs " " " " = hydro
BIGLICKER
15-12-2010, 21:14
Thanks


r O y.
neil_richardson
15-12-2010, 22:05
depends which country you're in...

Here in Australia:

Visual - 1 year
Hydro - 1 year


:)
Richard Mason
15-12-2010, 23:40
depends which country you're in...

Here in Australia:

Visual - 1 year
Hydro - 1 year


:)


And every year thereafter. My poor old Heiser 12L that I brought out from the UK was tested 20 odd times, twice in the UK and 18 x here so the equivalent of 100 years of life had it stayed in the UK. Made in 1978, bought in 1980, 32 years old and still going strong.
MarkM
16-12-2010, 01:26
And every year thereafter. My poor old Heiser 12L that I brought out from the UK was tested 20 odd times, twice in the UK and 18 x here so the equivalent of 100 years of life had it stayed in the UK. Made in 1978, bought in 1980, 32 years old and still going strong.
Probably more than 12L now too :)
Richard Whitcombe
16-12-2010, 02:24
When is a brand new cylinder due for its test? And, what test does it need???
Anyone know?


thanks

r O y.:eek:


2.5 years from manufacture date.

Visual tests are 5 years and hydros are 5 years but staggered by 2.5 years. So it always needs something every two and a half years and for the first time that date is from the manufacture date stamped on the tank.

First test on a new tank will be visual, then a hydro, then a visual and so on.

Other countries are different, aus as they say above seems to be yearly. Egypt is 6 monthly.
neil_richardson
16-12-2010, 05:36
6 monthly??

you jest...

visual or both?? as thats ludicrous...
bythesea
16-12-2010, 09:34
6 monthly??

you jest...

visual or both?? as thats ludicrous...

Is it? the amount of abuse those tanks get on the tourist boats it should be weekly...
MarkM
16-12-2010, 10:29
When hydrostatically testing cylinders you measure the expansion when pressurised at the TP (usually 1.5 X WP), then the % expansion left after the relieving of the pressure. It has to be the within limits set in your country.

Testing cylinders too often would soon make them fail as they would soon lose their elasticity and not return within limits after being over pressurised.
neil_richardson
16-12-2010, 11:56
and thats different to the barrier reef because!?!??

its kinda accepted over here, that its overtesting once every 12 months... but our excuse is the burst discs... in Egypt???
bythesea
16-12-2010, 13:36
If I put a little wink at the end of my posts will people then realise it was tongue in cheek? ;)
Richard Whitcombe
16-12-2010, 17:44
Is it? the amount of abuse those tanks get on the tourist boats it should be weekly...

Its ludicrous - they're massively shortening the lifespan of the tanks by doing them that often. I think yearly is stupid enough.
benltdiverdude
16-12-2010, 21:05
is this the same for ali Cylinders?
Richard Mason
16-12-2010, 22:29
is this the same for ali Cylinders?

Yep.
Richard Mason
16-12-2010, 22:34
When hydrostatically testing cylinders you measure the expansion when pressurised at the TP (usually 1.5 X WP), then the % expansion left after the relieving of the pressure. It has to be the within limits set in your country.

Testing cylinders too often would soon make them fail as they would soon lose their elasticity and not return within limits after being over pressurised.

That's what I thought too but I used a pair of hire cylinders only a couple of years ago that had been tested annually since 1975, so 37 tests, which is the same amount a UK cylinder would get in 185 years, yet they're still going strong and it's the same test as in the UK.

It's not that a big deal here, I only pay $30 per test, or about 20 quid in your money; I understand that UK test fees are far far higher.
ChristianG
16-12-2010, 23:37
That's what I thought too but I used a pair of hire cylinders only a couple of years ago that had been tested annually since 1975, so 37 tests, which is the same amount a UK cylinder would get in 185 years, yet they're still going strong and it's the same test as in the UK.
Actually that stands to reason, wherever in the world they get tested.

After all, if they fail the test they get snipped in half (may not be the same procedure elsewhere in the world but that sure is what happens here). If you ask nicely they'll snip the bottom bit so that you can turn it into an (yeccchhhh) ashtray and do another snip at the shoulder so that you could build the cylinder itself into, say, a video housing. Never tried that myself but plenty around here have and it works - after a fashion.

Edit/: Don't even think about trying that with a steel cylinder though, not unless you're superman.
benltdiverdude
17-12-2010, 20:47
Can someone briefly describe what happens in a visual test for me, i assume its more than just looking inside (id hope so for the price). sorry for deviating from the subject, it just got me thinking as my stage is off being visual tested at the moment.
Thanks Ben
PeteM
18-12-2010, 00:08
Can someone briefly describe what happens in a visual test for me, i assume its more than just looking inside (id hope so for the price). sorry for deviating from the subject, it just got me thinking as my stage is off being visual tested at the moment.
Thanks Ben

Look inside. check threads in neck and on valves using a "go/no go" gauge. Paper work. That is about it.
Terry
19-12-2010, 18:22
When PeteM says"have a look inside" I think that he means have a very good look using a dentists type mirror and a bright, forward facing inspection lamp. The inspector is looking for manf defects such as folds( Ive never seen one). As well as corrosion in general as well as specific corrosion pits.
Some years ago there was a problem with Ally tanks in that they encountered sustained load cracking in the thread area which can be easily picked up by a good quality visual although many used an eddy current tester which I am told does not work so well on recent ally tanks which have a different composition. Anyway the visual inspector does pay careful attention to the threaded area looking for cracks as these cracks can slowly propagate and cause tank failure. There is also a limit as to the amount of viable threads in the tank neck dependent upon tank WP.
When the report is written the radial location of any questionable mark is given on the report with reference to data that the manf has stamped on the cylinder.
I will leave it to PeteM to explain how the go,no go thread test works.

As a point of interest and in my opinion only, any Ally tank with a manf date prior to 1990 could be subject to SLC. There are various dates for various countries but 1990 is easy to remember.
Terry
benltdiverdude
19-12-2010, 21:02
Thanks for that, quite interesting, just thought i'd add for anyones interest that ally tanks , if they have run out of visual test for more than 6 months they need a full hydro test, i think i was about a week inside this date, but im glad i now know, phew...

Ben
PeteM
19-12-2010, 21:16
When PeteM says"have a look inside" I think that he means have a very good look using a dentists type mirror and a bright, forward facing inspection lamp.

Endoscope
Richard Mason
20-12-2010, 01:36
As a point of interest and in my opinion only, any Ally tank with a manf date prior to 1990 could be subject to SLC. There are various dates for various countries but 1990 is easy to remember.
Terry

We've had some excitement with aluminium tanks here - most, although not all dive shops now refuse to test or fill these tanks (http://www.aqua-scuba.com.au/images/news/Cylinder%20Filling%20-%20WHS.pdf).