1989 Luxfer cylinder VIP refusals

[PhilEllis]

All DOT3AL tanks manufactured under one of the following exemptions or
special permits: 6498, 7042, 8107, 8364, 8422;

All composite cylinders manufactured under one of the following exemptions:
7235, 8023, 8115;

All Walter Kidde DOT3AL scuba tanks;

Cliff Impact DOT3AL scuba tanks made before July, 1990;

Luxfer 80.8 cu. ft. scuba tanks (S80.8) made before May, 1987;

Luxfer 72 and 100 cu. ft. scuba tanks (S72, S100) made before August, 1987;

Luxfer 80 cu. ft. scuba tanks (S80) made before January, 1988;

Luxfer 50 and 92 cu. ft. scuba tanks (S50, S92) made before April, 1988;

Luxfer 30 and 63 cu. ft. scuba tanks (S30, S63) made before May, 1988;

Luxfer 40 cu. ft. scuba tanks (S40) made before June, 1988;

All other scuba tanks made in the U.S. before February; 1990 (except Catalina);

All scuba tanks not made in the U.S.

A look at this list also gives a little insight as to why so many scuba stores have adopted the rule that they will not fill any tanks "made before 1990"......

In a production fill environment, having a long list of various brands, sizes, and dates that switched off of the 6351-T6 alloy at various different times makes it more likely that an employee would miss a cylinder that should be excluded (this assumes you have made the decision to exclude 6351 cylinders) based upon the information stamped on the cylinder. Easily reading the stampings on old cylinders is even problematic. Using the final category listed above....."all other tanks made in the US before February 1990".....provides for a rule that simply requires looking and identifying the original hydro date.

I am not suggesting that this is the MOST ACCURATE way to segregate cylinders or that it is not subject to Type I errors....I am simply saying this represents a simple rule for application at the fill station. Remember, the population of cylinders that will be refused under this rule, in this year and the coming years, is a fairly small and continuously decreasing population, so it has impact on fewer and fewer cylinder owners as time passes.

Phil Ellis

 

[Gilldiver]

I have no real problem with a shop deciding not to do 6351 alloy ALUMINUM bottles and if I ran a shop I would most likely do the same. I have a real big problem with shops refusing to do ANY bottle older then 1990 or older then 20 years, including steels.

As was posted, sustained load cracking is only a problem with aluminum cylinders and the manufacturing dates of these cylinders is well known and documented. Shops that are refusing to fill aluminum cylinders with 6061 alloy or steels based on age are either fools, intellectually dishonest, or financially dishonest to their customers or any combination of such.

As all bottles inspectors have to be certified there should be no problem in being able to read the original Hydro dates and cross checking to a simple alloy date chart.

 

[captndale]

I had an experience similar to Phil's about 6 or 7 years ago. At the time, I owned a shop and I had a couple of tanks that had been vip'd, eddy current tested and hydro'd that had been sitting in the back of the shop, unused, for a couple of months since coming back from the hydro facility. I had a group coming in from out of state to do some technical diving and I needed another set of doubles. I had run out of steel tanks so I grabbed those two aluminum tanks and manifolded and strapped them together.

I charged them with O2 and He and asked one of my employees to do the air top-off. A few minutes later he came up to me and said that one of the tanks was leaking. I went back to the fill room and waved my hand around the manifold to locate the leak. I was surprised and alarmed when I felt the gas coming from the neck of one of the cylinders. I quickly opened the valves and left the room.

I sold my shop a number of years ago but I have a fill station in my garage where I do fills for myself, my buddies and my students. I still fill 6351 tanks, but I certainly understand why many shops do not. The difference is, when I do fills, the only one put at risk is myself.

 

[PhilEllis]

I have never heard of a shop refusing to fill steel cylinders on any date-based rule. There would be no justification for that.

Phil Ellis

I have no real problem with a shop deciding not to do 6351 alloy ALUMINUM bottles and if I ran a shop I would most likely do the same. I have a real big problem with shops refusing to do ANY bottle older then 1990 or older then 20 years, including steels.

As was posted, sustained load cracking is only a problem with aluminum cylinders and the manufacturing dates of these cylinders is well known and documented. Shops that are refusing to fill aluminum cylinders with 6061 alloy or steels based on age are either fools, intellectually dishonest, or financially dishonest to their customers or any combination of such.

As all bottles inspectors have to be certified there should be no problem in being able to read the original Hydro dates and cross checking to a simple alloy date chart.

 

[PhilEllis]

I had an experience to Phil's about 6 or 7 years ago. At the time, I owned a shop and I had a a couple of tanks that had been vip'd, eddy current tested and hydro'd that had been sitting in the back of the shop unused for a couple of months since coming back from the hydro facility. I had a group coming in from out of state to do some technical diving and I needed another set of doubles. I had run out of steel tanks so I grabbed those two aluminum tanks and manifolded and strapped them together.

I charged them with O2 and He and asked one of my employees to do the air top-off. A few minutes later he came up to me and said that one of the tanks was leaking. I went back to the fill room and waved my hand around the manifold to locate the leak. I was surprised and alarmed when I felt the gas coming from the neck of one of the cylinders. I quickly opened the valves and left the room.

I sold my shop a number of years ago but I have a fill station in my garage where I do fills for myself, my buddies and my students. I still fill 6351 tanks, but I certainly understand why many shops do not. The difference is, when I do fills, the only one put at risk is myself.

Dale, in the incident that I related, there was one thing that really rattles me......

We have visually inspected and failed MANY aluminum cylinders due to cracks in the neck that were visible during well-lighted, deliberate, magnified inspection. Now, they are easy to miss if you are sloppy, but with close inspection, they can be found.

We had inspected the cylinder I discussed later with just as much care and consideration as we do any other cylinder....in fact, maybe a little more care given the date. We simply did not see ANY evidence of a neck crack. Given the hydro and visual plus inspection just two days earlier, not finding a problem with the neck was basically expected.

Thirty minutes later, an obvious crack. Now, maybe we missed it. Maybe we made a mistake. However, I just went back and looked at that cylinder again 10 minutes ago....the crack is now visible with the naked eye. I can tell you, even with magnification and various light angles, even with probing picks.....it was not evident 30 minutes before we attached it to our fill panel in May of 2007..

Phil Ellis

 

[DA Aquamaster]

One of the things that bothers me is a discussion I had with the owner of the shop/hydro facility I worked at a few years ago.

His feeling was that the regs called for the VIP before the hydro test. That makes sense in regard to ensuring you don;lt waste time on a tank that fails the VIP. But it does nto make sense in regard to ensuring the tank is now dry and unrusted and it does not makes sense in that the tank is not inspected after the stress of the hydro.

Interestingly, this same gentleman had previously showed me a tank that had passed the VIP and eddy current inspection they got hydro tested and came out of the tank spurting water out the shoulder/neck area. Had this crack been slightly less propogated it could have concievably passed the inpsection and failed in service in the manner you encountered. The scary part is he did not appreciate the disconnect betwene the regs and the reality of the situation.

My thoughts are that annual eddy current inspections still make sense at the dive shop level and that they are best done after the hydro test, not before. Frankly if I owned a shop and knew the test facility eddy inspected prior to hydro, I'd do my own eddy current inspection on the tank p[rior to filling it.

 

[PhilEllis]

One of the things that bothers me is a discussion I had with the owner of the shop/hydro facility I worked at a few years ago.

His feeling was that the regs called for the VIP before the hydro test. That makes sense in regard to ensuring you don;lt waste time on a tank that fails the VIP. But it does nto make sense in regard to ensuring the tank is now dry and unrusted and it does not makes sense in that the tank is not inspected after the stress of the hydro.

Interestingly, this same gentleman had previously showed me a tank that had passed the VIP and eddy current inspection they got hydro tested and came out of the tank spurting water out the shoulder/neck area. Had this crack been slightly less propogated it could have concievably passed the inpsection and failed in service in the manner you encountered. The scary part is he did not appreciate the disconnect betwene the regs and the reality of the situation.

My thoughts are that annual eddy current inspections still make sense at the dive shop level and that they are best done after the hydro test, not before. Frankly if I owned a shop and knew the test facility eddy inspected prior to hydro, I'd do my own eddy current inspection on the tank p[rior to filling it.

I cannot quote you the regs or references, but I do think I remember quite well how it was explained to me by a person I trust to have knowledge and understanding of the issue.....

the "visual" inspection required as part of the 5 year re-qualification test is an inspection to determine if there is any visual grounds for not accepting the cylinder for hydrostatic test (I don't know what these would be...damage, maybe?). Therefore, it MUST be done in advance of the hydro inspection to serve the designed purpose.

Our hydro station, who does mostly industrial gas and fire extinguishers, admits that they do not inspect for things that might make the cylinder unpleasant or unsafe for breathing purposes. Their entire inspection protocol (physical and visual) is to test structural integrity.

Phil Ellis

 

[dannobee]

the "visual" inspection required as part of the 5 year re-qualification test is an inspection to determine if there is any visual grounds for not accepting the cylinder for hydrostatic test (I don't know what these would be...damage, maybe?). Therefore, it MUST be done in advance of the hydro inspection to serve the designed purpose.

Phil Ellis

For gouges, dents and the like. Also for signs of being fire damaged and such.

 

[Scared Silly]

A look at this list also gives a little insight as to why so many scuba stores have adopted the rule that they will not fill any tanks "made before 1990"......

In a production fill environment, having a long list of various brands, sizes, and dates that switched off of the 6351-T6 alloy at various different times makes it more likely that an employee would miss a cylinder that should be excluded (this assumes you have made the decision to exclude 6351 cylinders) based upon the information stamped on the cylinder. Easily reading the stampings on old cylinders is even problematic. Using the final category listed above....."all other tanks made in the US before February 1990".....provides for a rule that simply requires looking and identifying the original hydro date.

I am not suggesting that this is the MOST ACCURATE way to segregate cylinders or that it is not subject to Type I errors....I am simply saying this represents a simple rule for application at the fill station. Remember, the population of cylinders that will be refused under this rule, in this year and the coming years, is a fairly small and continuously decreasing population, so it has impact on fewer and fewer cylinder owners as time passes.

Phil Ellis

If this is the attitude the scuba industry is in deeper excrement than I thought.

1) There are other cylinders that should not be filled - i.e. illegal. At least, filling 6351 cylinders is legal.

2) If the markings on any cylinder are not clear it should not be filled.

3) If an employee can not read and understand the markings then they should not be filling cylinders.

4) If an employee is not smart enough to see a date and not be able to look up on a chart whether it falls into the 6351 or 6061 category then they should not be filling cylinders.


Now that said I do not have a problem with a shop declining to fill 6351 cylinders. For that matter Phil it was your story that convinced me of this.

I have never heard of a shop refusing to fill steel cylinders on any date-based rule. There would be no justification for that.

Phil Ellis

I have personally seen this in the Lower Florida Keys (specifically Ramrod Key). It said something to the affect "No tanks made before XXXX will be filled". Now the shop could well have meant AL cylinders but that is not what the sign said and I did not ask for details. However, afterwards I contacted the local distributer for their AL cylinders to let them know of their practice. They were not selling steel cylinders (or at least none were in the shop).

 

[Gilldiver]

In a production fill environment, having a long list of various brands, sizes, and dates that switched off of the 6351-T6 alloy at various different times makes it more likely that an employee would miss a cylinder that should be excluded (this assumes you have made the decision to exclude 6351 cylinders) based upon the information stamped on the cylinder. Easily reading the stampings on old cylinders is even problematic.

Any policy that says that a bottle made before a specific date will not be filled implies that the original hydro date has to be read. If you can read the original hydro date, then you should be able to see the manufacturers mark which is just to the left next to the date. If you can't read the date or the mark, don't fill the bottle.

But the above seems to imply that the person who is filling a bottle can read numbers but not manufacturers marks.