Yeah, that's the issue with using smaller, less expensive cylinders..... you have to really up the PSI to achieve any decent level of tonnage. Therein lies it's own dangers.
I honestly don't like to see a press pushing the PSI you mentioned (2550 psi), which is why I always try to pressure folks into NOTHING LESS than a 6" dia cylinder. Sure, the lines and other parts of the actual hydraulic system are typically rated for double that pressure, but forging presses are very unique in that they live/work in torturous conditions with usually not the best safety measures in place.
I always point out to consider what would happen if a hot piece of steel got onto a line without notice....even a pin hole leak would cut you in half like a light saber..... not to mention it would very likely be a flame thrower too. That same torturous environment.... consider the repetitions and the constant heating/cooling cycles, and you want to WAY overbuild the presses structure.
Bigger cylinders, with lower working pressures are the key to SAFE (at least as safe as a forging press can be) forging presses, just as ridiculously overbuilding the structure is the key to structural longevity.
All too often, those who offer forging presses for public sale fail on the side of building everything to just barely meet a relatively low standard, sometimes in the name of making a buck, but more often than not, I've found it to be a situation where those offering the tool (in this case a forging press) without ever having actually used one, day in and day out, over an extended period of time. If they had, every press out there would be built like Orange Crush.
