To clarify my point... Hydraulic accumulators do not have a specific code applied to them. Thus, most manufactures can get away without following it.
Hydac treats them as non-fired pressure vessels and follows ASME and the applicable European standards. However, there are many large companies out there that do not. Call it illegal if you want, but I challenge you to out-smart there legal guys.
regardless, I'm done with this post, the guy isn't asking any more questions, we should all just drop it...
Cabbages, knickers, It hasn't got A BEAK!