Old steels denied fills due to store "policy"

[Ana]

But please, do man'splain how hydros work.

I did get the feeling I was being man'splained to.

...love it when I get the "little lady" treatment.

 

[Bob DBF]

My guess is those tanks don't get VIP every year either. Tanks don't need to be perfect, just up to the job, hydro testing is the standard for that, if it passes it's up to the job.

The VIP was a measure to check for damage from the intrusion of water into tanks, which was prevelent at the time. Industrial cylinders, due to their operation, have no such issues. Due to the changes in diving over the intervening decades, I would bet that the VIP could be dropped without issue.

My dedicated "boat tank" Nitrox filled on the SoCal dive boats, had the same little bit of flash rust from one hydro to the next.


Bob

 

[TrimixToo]

It's also true in RI and MA I do think however CT has a LDS with hydro testing facility. As a general statement it's accurate but inclusive.

Diver's Cove.

 

[Wookie]

I did get the feeling I was being man'splained to.

...love it when I get the "little lady" treatment.

May I carry your tanks as well?

Here, let me get those while you make me a sammich...

 

[Wookie]

The VIP was a measure to check for damage from the intrusion of water into tanks, which was prevelent at the time. Industrial cylinders, due to their operation, have no such issues. Due to the changes in diving over the intervening decades, I would bet that the VIP could be dropped without issue.

My dedicated "boat tank" Nitrox filled on the SoCal dive boats, had the same little bit of flash rust from one hydro to the next.


Bob

My wife the VIP person at her LDS says to bite your tongue. She tumbles 50 cylinders a year and whips another 20, she just fails the wet aluminum ones.

 

[Ghost95]

If its all the same to you, I'll r ate my years on metallurgical and NDT experience above that of someone who's done a 1 or 2 day "inspection course" YMMV

For the record, I recently carried out Eddy current (VE) and Ultrasonic inspections on a batch of personal cylinders belonging to me and a couple of friends (roughly 60) mainly steels but a few Al 80 and S40's for piece on mind

I found 1 small neck crack (not detectable by vis) and 2 material voids

All had just passed hydro and vis

Just curious about a couple things, what tanks failed, Aluminum or steel, and how?

And the voids, are those a manufacturing defect or do they develop over time? I really know nothing about voids in tank material.

 

[Diving Dubai]

Just curious about a couple things, what tanks failed, Aluminum or steel, and how?

And the voids, are those a manufacturing defect or do they develop over time? I really know nothing about voids in tank material.

Both defects were on Steel tanks, but both defects are not material specific, i.e. they could have easily been on an Ali cylinder

The void, would be (with 99%certainty) be gas porosity (gas bubble) which is a defect that arises in the production of the raw steel, which has not been detected (or been deemed to be an acceptable defect at that grade of material) during manufacture at the mill

We obs binned the tank with tiny neck crack, but the tank with void was a harder call - because while I know its rough width you cant' tell depth by examining from one side, and it was on a 1998 cylinder, which had been acquired second hand, but no provenance on how much it had been used

In the end we binned that cylinder too as we jointly have so many

 

[Ghost95]

Thanks for the clarification. I really expected the crack to be in the aluminum tank.

The void is interesting. If it's a manufacturing defect, then time or use wouldn't be a factor would it? You could conceivably buy a brand new tank tomorrow that had the same defect and everyone would happily fill it but they would be at the same risk as filling the tank you took out of service because without the testing you conducted you never know.

I know visuals are subjective but hydros's are not. If a tank has been abused to the point of being unserviceable, isn't that what the hydro is designed to detect?

The argument is that if a steel tank from 1963 passes it's inspections then it hasn't been abused. If it has been abused then the metal will have changed structure/characteristic/something and it won't pass. Am I kind of understanding this correctly?

Of course any shop can make a policy on what they fill but it seems arbitrary to just put an age limit on STEEL tanks. If I were a shop trying to limit incidents/liability then saying that they won't fill any tank that they have not inspected would make more sense.

Thanks for the reply. This thread has been an interesting read. I can't believe I got through all 38 pages.

 

[Magnus Lundstedt]

You know nothing about our coustomer service. We go to hell and back for our coustomers. We run a safe operation . Just cus I wont fill an old tank dosnt mean we dont care about our coustomers. Again I'll gladly offer a complementary rental if we refuse a fill. So you can still get your dive in.

Our fill station is small but mighty it serves our needs in our low volume operation. We do alot with less. And yes that is an old photo from our last move.

The next closest fill station is 60 miles away and closes at 2 on Saturday. I'll open at 10 PM if you need a fill and your tanks aren't older than me

As for our coustomer service I have on more than one occasion met coustomers at the highway to hand deliver our personal lights, dry suits, sorb , sensors, any thing to make sure our loyal coustomers dont miss a dive. We often hand over our own regs on the boat when a charter passengers gear fails, I have patched dry suits with the diver geard up and assisted in the recovery of a new shearwater that slipped off a divers wrist durring an entry.

This past season we made a 30 mile round trip durring a surface interval to pick up 2 divers who had missed the evening ferry and had to catch the morning run. That's at least $200 in fuel that we didn't up charge for.

If you want to know who I really am? call Dan Humble or Wayne Green they will fill you in on who answers the call when the worst moments of people's life happen.

You are so quick to cast stones at me and operations like force e but you dont know who or what you are talking about.


You can't shearch independent sdi instructors with that tool.

It does not mather how good your operation is in all other regards, if i am not able tpo use it becouse you don not fill my tanks.

IUts like having the best, most beautiful, fastest car in the world. but if it is 2 wheels short, it do not take me anywhere.

 

[Diving Dubai]

The void is interesting. If it's a manufacturing defect, then time or use wouldn't be a factor would it? You could conceivably buy a brand new tank tomorrow that had the same defect and everyone would happily fill it but they would be at the same risk as filling the tank you took out of service because without the testing you conducted you never know.

Voids and or [material] inclusions are weird things Yes they can be in a component and remain dormant with no risk for the life of that component

Or they can be "triggered" at some point, and become an initiation point.

While Hydro is a good test, its there to principally test that the cylinder material has maintained its mechanical properties. If during the test it enlarged a defect to the point the cylinder fails, then consider that a bonus.

There is also a tolerance in which the cylinder must be within. So a cylinder can be right at the limit and still pass

By convention in inspection, a defect should be able to remain undetected for 3 inspection cycles not failing until after the 4th and so in theory tanks can be in use with defects that the statics and predictions say are okay, and for 99.99% of the time they are...

You should also consider different regions have different inspection frequency, and all use the same data

US = Annual vis, 5 yr hydro

UK = 2.5yr vis 5 yr Hydro

Aus = Annual Vis and hydro

Who is right and who is wrong.

Also and especially with used tanks what's the provenance? How hard have they been used, how many hyros over their life, (in the case of steels) how many times have they been tumbled (which reduces material wall thickness)

Personally I bin tanks that are over 20 years old. Tanks are cheap

People will fork out $1000 every so often for the latest and greatest dive computer But want to hang on to old tanks for as long as possible. Their choice of course, I just don't get it