Mike,
I have to agree with you and Chet about being concerned with leakage...
If this was something that had to be done for whatever reason which more than likely is economic because of pricing comparisons then, at least perform some sort of NDT (PT or MT or even UT), and hardness testing if possible to find out if there is'nt even the remote possibility of failure from the inside out once the cylinder is put to use...
Jimwelds, Mike is right, safety first!!! Btw, it might be less expensive in the long run to order it to your specs from a variety of hydraulic equipment manufacturers... Most of them do custom work orders for which they will assume liability!!! Jimwelds, will you assume liability???
Food for thought...
Respectfully,
SSBN727 Run Silent... Run Deep!!!