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Unread 10-01-2014, 13:18
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Re: Pneumatic Ball Puncher

Quote:
Originally Posted by Al Skierkiewicz View Post
Brandon et al,
During inspection, launchers may have to demonstrated for "dry firing" to see if they are in fact safe with no ball present. Having no external hard limit for cylinders quite frankly scares me. While the working pressure is only 60 psi, a cylinder can impart quite a bit of force on the piston and the end assy with no system resistance. I have seen enough catastrophic failures to worry about this design choice. Please prototype with extreme safety in mind.
While a 3/4" cylinder with good flow to it moves pretty quick, and we always make strong efforts to work and design safely, I would be amazed if an unmodified COTS piston operated at less than 50% max psi recommended by the manufacturer (125psi max, operated at 60psi per FIRST rules) failed due to dry firing. This would be a major design flaw by the manufacturer. Now if we dry fired it at 125+ psi many times and it failed that's another thing. We will of course exercise caution but a failure of this type with no other damage or modification seems implausible especially given the reliability of our product manufacturers.
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