Quote:
Originally Posted by JesseK
That may be an artifact from the old days of pneumatics, and the manufacturer changed the spec afterwards? There are plenty of pneumatics with similar scenarios, and I think the only thing we can do is recommend modern alternatives, like you've done. I'm sure there are other parts & rules which are based upon what was available 8+ years ago. The GDC has done a great job modernizing the rules, and we as a community can continue to keep them on their toes  .
For example, Festo makes some great 90 & 180-degree rotary pneumatics with an awesome form factor, but they're all only rated for 8 bars of pressure. I'm willing to bet it's 8 bars only because they rounded down from the actual safe value. This is 116 psi, therefore illegal in 2015. After Champs, I plan to write a letter to FIRST asking about the reasoning behind the number of 125 psi for all pneumatic parts. I bet it's because of this regulator you've listed - if it fails, then 110 psi goes to all parts downstream. Yet what if we were allowed to only store 105 or 110 psi of air for pneumatics - would that alleviate the safety concerns? |
That would necessitate a different pressure switch. The reason the rule is 125 PSI is because The pressure switch maxes out at 120 and the relief valve is supposed to be set to 125. That way if something goes wrong the relief valve will open before anything explodes.
Sure, we could have different standards. I'm sure FIRST could find a pressure switch that opperates at a lower pressure, and require the relief valve to open at a lower pressure, and thus allow more items to be used in the system. Do that, though, and a bunch of teams will scream about how they just "lost" available storage by having to store at a lower pressure, and how they now have to add more tanks to make up the volume difference, etc.