Tank without Hydro

[chaseyerkey]

I recently bought a cylinder specifically a Luxfer AL40 off of Facebook marketplace after buying it, I noticed it doesn’t have a Hydro stamp. Would anybody know why that would be? I thought they came with one from the manufacturer. All the markings are the same on my other Luxfer cylinders, other than the lack of a Hydro stamp it’s currently filled with about 1000 psi of O2 I was told it was used as a deco cylinder a few years ago, but has been sitting around. any help would be appreciated

 

[Divin'Papaw]

The manufacture/initial hydro is stamped as part of the serial number on the crown of the tank. I have two Luxfer AL40s. You’re looking for MMAYY that should be right between M4141 and S040. Mine are 11A14 and 11A15 for example. That is the manufacture (initial hydro) date. Nov of 2014 and Nov of 2015 for my two.

 

[chaseyerkey]

The manufacture/initial hydro is stamped as part of the serial number on the crown of the tank. I have two Luxfer AL40s. You’re looking for MMAYY that should be right between M4141 and S040. Mine are 11A14 and 11A15 for example. That is the manufacture (initial hydro) date. Nov of 2014 and Nov of 2015 for my two.

Thanks I figured this out right before reading the replies. I usually buy used tanks so I never knew what manufacturer Hydro looked like.