I'm not home with a book, but 6688 sounds like the WK special permit that has passed. I believe you have a junk tank, I can confirm later.
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Weren’t SP6688 tanks mostly Norris?I'm not home with a book, but 6688 sounds like the WK special permit that has passed. I believe you have a junk tank, I can confirm later.
When you find yourself in a hole it is often a good idea to stop digging.I stand by my statement of the binder page being a dumbed down version of DOT regs. I guess I could go with simplified.
Badmouthing PSI PCI is hardly “correct”. Then doubling down on them is pretty bad form too. My late father used to say “pulling out your left foot to make way for your right”.@grf88 I like my shovel tyvm. I misread the numbers on the tank and stated as such. I saw I read tech data daily for aviation electronics troubleshooting and repair. That paper power point is dumbed down. I'm not saying it isn't accurate, but my statements are not incorrect.
I'm saying the power point is dumbed down, not PSI. Take that for what it is. Technical details or picture books get the job done in most cases.Badmouthing PSI PCI is hardly “correct”. Then doubling down on them is pretty bad form too. My late father used to say “pulling out your left foot to make way for your right”.
Just to back this upAs posted, by others. Norris Industries SP6688 and Kaiser SP6576 permits expired by 1979. These cylinders are not serviceable in the US. The OP has scrap metal.
Regarding other earlier special permits, Luxfer and Walter Kidde continued production under SP6498, E6498 or SP7042, E7042 until the DOT formalized the aluminum cylinder category 3AL in July 1982. Those can be requalified with VE.