Size of my cylinder ?
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runsongas
Contributor
luxfer aluminum 80 probably. measure the height and if it is 26 inches tall, it is a al80.
is there an overstamped 3AL over the SP6498? is there a VE in the latest hydro? you will want to check for those to make sure it has a valid hydro
there is a good chance the tank is 6351 alloy, i would have passed on buying such a tank
http://www.scubaboard.com/forums/ta...66-my-cylinder-made-bad-alloy-aka-al6351.html
is there an overstamped 3AL over the SP6498? is there a VE in the latest hydro? you will want to check for those to make sure it has a valid hydro
there is a good chance the tank is 6351 alloy, i would have passed on buying such a tank
http://www.scubaboard.com/forums/ta...66-my-cylinder-made-bad-alloy-aka-al6351.html
Def an AL tank....and if it does not have the 3AL and VE as stated above you do NOT have a valid hydro.....someone is BSing you. In between the month and year of the hydro is another symbol, that is who supposedly hydro'ed it.
Scared Silly
Contributor
The above two posts are spot on.
DOT-SP6498 == Special permit 6498 which was issued to Luxfer in 1971 to mfg aluminum cylinders. Depending on the cylinder's age it could be 72 or 77 cu.ft. What is the cylinder diameter?
DOT-SP6498 == Special permit 6498 which was issued to Luxfer in 1971 to mfg aluminum cylinders. Depending on the cylinder's age it could be 72 or 77 cu.ft. What is the cylinder diameter?
It's quite likely the hydro test has been done as failing to add the 3AA stamp isn't a new problem.
The 3AL standard was adopted in July 1982 and all SP6498 and E6498 (Luxfer, 6351-T6 alloy) scuba tanks as well as SP7042 and E7042 (Walther Kidde, 6351-T6 alloy) scuba tanks (and other AL tanks under permits 922, 7042, 8107, 8364, 8422) were supposed to be stamped "3AL" at their next requalification. However, you'll still find them without the 3AL stamp 30 years and 6 requalifications later. Early on it was RINs being unaware of the "new" requirement or just being lax. Now, however the requirement is 30 years old and the number of affected tanks is very small, so once again it's a case of RINs not being aware of it, and not screening for it.
SP6688 (Kaiser) and SP6576 (Norris Industries) tanks were not renewed by their manufacturers under the new 3AL standard so they were supposed to be removed from service at the next requalification. For the most part they have been retired, and you rarely see them.
The "VE" requirement has been around since January 1, 2007, but it does not apply to tanks used in CO2 service, and it's still not unheard of to see 6351-T6 alloy tanks not "VE" stamped. You'll want the shop to do a Visual Plus or eddy current inspection in any case on an annual basis. I've never been impressed with the visual inspection being done prior to the hydro test anyway on a 6351-T6 alloy tanks as I've seen tanks with no detectable crack with noticeable cracks after the hydro test, and in one case spurt water out the shoulder due to an undetectable crack that propagated to the point of failure. You really do want your local dive shop backstopping the RIN on this inspection.
It's more common to see older 6061-T6 tanks needlessly stamped "VE". The industry standard is to consider any made prior to 1990 as being made from 6351-T6 alloy, even though Catalina started making 6061-T6 alloy tanks in 1986, and Luxfer started switching to 6061-T6 alloy in May of 1987 and was entirely switched to 6061-T6 alloy in June 1988.
6351-T6 alloy tanks:
All aluminum tanks under Special Permit # 6498, 922, 7042, 8107, 8364, 8422
All Walter Kidde 3AL Cylinders
All Cliff Impact Cylinders
All Luxfer S80.8 Manufactured Prior May 1987
All Luxfer S72 and S100 Manufactured prior to August 1987
All Luxfer S80 Manufactured prior to January 1988
All Luxfer S50 and S92 Manufactured prior to April 1988
All Luxfer S30 and S63 Manufactured prior to May 1988
All Luxfer S40 Manufactured prior to June 1988
Luxfer absorbed the Walter Kidde's scuba tank operations in 1989, so those were the last of the 6351-T6 alloy tanks.
All Catalina tanks and any Luxfer tanks after the above listed dates are made from 6061-T6 alloy.
The 3AL standard was adopted in July 1982 and all SP6498 and E6498 (Luxfer, 6351-T6 alloy) scuba tanks as well as SP7042 and E7042 (Walther Kidde, 6351-T6 alloy) scuba tanks (and other AL tanks under permits 922, 7042, 8107, 8364, 8422) were supposed to be stamped "3AL" at their next requalification. However, you'll still find them without the 3AL stamp 30 years and 6 requalifications later. Early on it was RINs being unaware of the "new" requirement or just being lax. Now, however the requirement is 30 years old and the number of affected tanks is very small, so once again it's a case of RINs not being aware of it, and not screening for it.
SP6688 (Kaiser) and SP6576 (Norris Industries) tanks were not renewed by their manufacturers under the new 3AL standard so they were supposed to be removed from service at the next requalification. For the most part they have been retired, and you rarely see them.
The "VE" requirement has been around since January 1, 2007, but it does not apply to tanks used in CO2 service, and it's still not unheard of to see 6351-T6 alloy tanks not "VE" stamped. You'll want the shop to do a Visual Plus or eddy current inspection in any case on an annual basis. I've never been impressed with the visual inspection being done prior to the hydro test anyway on a 6351-T6 alloy tanks as I've seen tanks with no detectable crack with noticeable cracks after the hydro test, and in one case spurt water out the shoulder due to an undetectable crack that propagated to the point of failure. You really do want your local dive shop backstopping the RIN on this inspection.
It's more common to see older 6061-T6 tanks needlessly stamped "VE". The industry standard is to consider any made prior to 1990 as being made from 6351-T6 alloy, even though Catalina started making 6061-T6 alloy tanks in 1986, and Luxfer started switching to 6061-T6 alloy in May of 1987 and was entirely switched to 6061-T6 alloy in June 1988.
6351-T6 alloy tanks:
All aluminum tanks under Special Permit # 6498, 922, 7042, 8107, 8364, 8422
All Walter Kidde 3AL Cylinders
All Cliff Impact Cylinders
All Luxfer S80.8 Manufactured Prior May 1987
All Luxfer S72 and S100 Manufactured prior to August 1987
All Luxfer S80 Manufactured prior to January 1988
All Luxfer S50 and S92 Manufactured prior to April 1988
All Luxfer S30 and S63 Manufactured prior to May 1988
All Luxfer S40 Manufactured prior to June 1988
Luxfer absorbed the Walter Kidde's scuba tank operations in 1989, so those were the last of the 6351-T6 alloy tanks.
All Catalina tanks and any Luxfer tanks after the above listed dates are made from 6061-T6 alloy.
First of all, I apologize for my late answer. I did not realize that anybody answered as I had no notification.
I am in New Zealand so I guess rules may change a bit. Over here I found that the laxity is sometimes shocking, but anyway I confirm I do have a certificate from an accredited shop which says the cylinders has past in October 2015.
There is a lot of stamps over the years from hydro testing, the oldest one I can read is from 1972. There is also an old sticker from "aqualung US Divers". The last stamp also says "TP2 8.5MPA WC 11.9Kg". I understand the weight but not sure about the meaning of the "TP2".
Diameter 6.9 inch and Length 28 inch. That things is positively buoyant.
I am in New Zealand so I guess rules may change a bit. Over here I found that the laxity is sometimes shocking, but anyway I confirm I do have a certificate from an accredited shop which says the cylinders has past in October 2015.
There is a lot of stamps over the years from hydro testing, the oldest one I can read is from 1972. There is also an old sticker from "aqualung US Divers". The last stamp also says "TP2 8.5MPA WC 11.9Kg". I understand the weight but not sure about the meaning of the "TP2".
Diameter 6.9 inch and Length 28 inch. That things is positively buoyant.
runsongas
Contributor
TP stands for test pressure. looks like the test pressure is 285 bar, which puts the service pressure at 214 bar or so. (i think NZ only tests to 4/3 pressure, someone else can correct me). at 214 bar and 11.9 liters volume (WC = water capacity, 11.9kg = 11.9 liters), you get about 2546 liters or 90cf. if NZ is testing to 3/2 TP, then the working pressure is 190 bar and you end up with a 80cf tank.
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