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Unread 18-01-2016, 08:01
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FRC #2177 (The Robettes)
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Re: Interpretation of R77-D

Quote:
Originally Posted by JesseK View Post
It is such a shame the limit is 120 psi. So many metric cylinders are rated for 8 bars, which is 116 psi. Surely the engineers of the metric cylinders rounded down to 8 bars after they added in a margin for safety.
From the bottom of page 4 in the Robot Rules:
Quote:
Some of these rules make use of English unit requirements for parts. If your team has a question about a metric-equivalent part’s legality, please e-mail your question to frcparts@firstinspires.org for an official ruling. To seek approval for alternate devices for inclusion in future FIRST Robotics Competition seasons, please contact frcparts@firstinspires.org with item specifications.
I would call an 8 bar pneumatic device to be a "metric equivalent", given how close it is to 120 psi. I know, bars and psi aren't really English/metric, but the same principle applies, I think.

I've also seen teams contact a parts manufacturer to get more details on the ratings. Often, once explaining the situation, they can get the manufacturer to provide them with some sort of documentation that says "yeah, 120 psi is perfectly safe".
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