Pressure Regulator

[Camren]

Our team has purchased an SMC percision regulator Model NIR202 and we were wondering (even after trying to interperet the rules) If it is legal. Our interpertation is that it is legal because even though the max bypass is above 60 psi but so is the norgren one that we got in the KOP has a maximum bypass above 60.

[IndySam]

[R74]
“Working” air pressure on the Robot must be no greater than 60 psi. All working air must be provided through one primary Norgren adjustable pressure regulator.

nope

Edit: The big reason for this restriction is that many inspectors are not pneumatic experts and making teams use the same regulator simplifies inspection. I don't think this rule will change.

[kevin.li.rit]

[R74]
“Working” air pressure on the Robot must be no greater than 60 psi. All working air must be provided through one primary Norgren adjustable pressure regulator.

nope

Edit: The big reason for this restriction is that many inspectors are not pneumatic experts and making teams use the same regulator simplifies inspection. I don't think this rule will change.

Does that mean one could interpret this as they have to use the norgen, but also able to use another regulator down stream?

[IndySam]

Does that mean one could interpret this as they have to use the norgen, but also able to use another regulator down stream?

Yes but be prepared with the paperwork to show it's legality.

[Camren]

so in all technicalities this (http://resources.norgren.com/document_resources/pdf/R38.pdf) would be legal. I'm unsure of the difference between an instrument regulator and a pressure regulator I just think its a more precise regulator. Also dies anyone know why the use of air filters isn't allowed?

[Gdeaver]

I see that the regulator can be relieving and non-relieving. Any regulator should vent excess pressure created down side of the regulator. If a regulator was set for 60 psi and a cylinder was mechanical compressed the pressure above 60 psi should be vented. Do I have it right?

[briansdargon]

I think the regulator you have the ability of reducing and non-relieving. An appropriate regulator should release unwanted stress designed down part of the regulator. If a regulator was set for 60 psi and a cyndrical tube was technical compacted the stress above 60 psi should be venting. You should consider these things.

[Al Skierkiewicz]

The rule refers to the one Norgren regulator to provide the primary working air to the robot. This regulator may be followed with other regulators set to pressures lower than 60 psi if desired provided all other rules are followed. Frequently teams attempt to limit pneumatic activity by providing lower actuating pressure to certain devices. This rule is in place simply to insure that every team uses the same energy to provide motion on their robot, namely 60 psi working pressure at a specific flow rate/volume.

Also in the rules...
[R71]
The only pneumatic system items permitted on 2012 FRC Robots include the items listed below.
D. Solenoid valves that are rated for a maximum working pressure that is less than 125 psi rating mandated above are permitted, however if employed, an additional pressure relief valve must be added to the low pressure side of the main regulator. The additional relief valve must be set to a lower pressure than the maximum pressure rating for the solenoid valve.
G. Pressure regulators with a maximum bypass pressure of no more than 60 psi,

Caveat: Rules are quoted from the 2012 rulebook, 2013 rules may be different.

Answering while Indy posted... Camren, no, that is not a legal primary regulator. Air filters? If you are asking about outlet silencers, many teams use them. If you are asking about intake filters, the compressor has them incorporated in the design.

[IndySam]

so in all technicalities this (http://resources.norgren.com/document_resources/pdf/R38.pdf) would be legal. I'm unsure of the difference between an instrument regulator and a pressure regulator I just think its a more precise regulator. Also dies anyone know why the use of air filters isn't allowed?

Technically I guess you could argue that it would be correct but why would you go to all that trouble?

If a team pulled that trick on me the rest of their inspection would be like a root canal :)

[FrankJ]

Largely conjecture here since I am not on the rules, committee... But the pneumatic rules seem to be written to keep the pneumatic system safe with minimal knowledge by the volunteer inspectors. (Absolutely no dig intended for the many volunteers who freely give their time & cannot be experts in everything.) But it makes very difficult to source parts that meet the literal interpretation of the rules.

KOP parts are by definition legal. A part identical to but not the same part number, mfr may not be legal. For example only a specific battery is legal although it a standardized battery with many equivalents. Same with regulators.

In the past we have used regulators downstream of the Norgren 60 PSI regulator for elements that needed a lower pressure. I believe we used a Norgren, so it was legal by definition, but the inspector did not look that closely at it. Having somebody able to clearly explain how the robot works is helpful to the inspector. What ever makes their job easier makes the inspection go smoother. At least that has been my experience.

Back in the day pneumatic controls where used extensively where electronic do an easier & better job now. Pneumatic PID controllers are still used in places where it is inconvenient to use electrics. Pneumatic valve actuators are still pretty common. Controls & actuators typically run on lower pressure (around 20 PSI). Instrument regulators are generally able to set a lower pressure, better quality & more precise that a GP regulator, but they both do the same function. Probably easier to find a First legal instrument regulator because of the lower working pressure.

[Al Skierkiewicz]

Frank,
While inspections are considered, the decision is not solely based on ease of inspections. In this case safety and equality are the deciding factors. Rookie inspectors and those not familiar with pneumatics are asked to call in the LRI or someone knowledgeable to assist with identification.

[FrankJ]

Sorry I did not mean to imply that the rules where written just to make things simple. Of course safety is a higher priority. On the other hand having 40 to 60 robots to inspect before qualification matches means the inspectors do not have a lot of time to spend on robots as a group. Having the robot well laid out & some who understands how their robot was built to the rules & can clearly explain it speeds the inspection.