High Flow Solenoids

[3a11]

My team is interested in using high flow solenoids for an aspect of our robot. Unfortunately, we know close to nothing about them. Can anyone provide some information about their use and where we could purchase them? Thank you!

[Bryce Paputa]

Trying to get faster than us? Good luck.

I haven't ever used them. Make sure to minimize the amount of tubing as it'll add resistance. Adding a tank between the regulator and the solenoid might also help reduce resistance from the regulator.

[IKE]

Be careful to use legal ones. The rules have been opened up quite a bit, and currently state:
R66 The only pneumatic system items permitted on 2015 FRC ROBOTS include the items listed below.
A. Items available in the KOP (except as noted in I),
B. Pneumatic pressure vent plug valves functionally equivalent to those provided in the KOP,
C. Solenoid valves with a maximum 1/8 in. NPT port diameter,
D. Solenoid valves that are rated for a maximum rated 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,
E. Additional pneumatic tubing, with a maximum 0.160 in. inside diameter, functionally equivalent to that provided in the KOP,
F. Pressure transducers, pressure gauges, passive flow control valves (specifically “needle valves”), manifolds, and
connecting fittings,
G. Pressure regulators with a maximum outlet pressure of no more than 60 psi,
H. Pneumatic cylinders,
I. Pneumatic storage tanks (with the exception of White Clippard tanks P/N: AVT-PP-41), and
J. Compressors compliant with R68.

************************************************
My emphasis added.
In previous years, there was a maximum "Cv" rating. this year, it only calls out an 1/8 NPT port size. "High Flow" will be the highest "Cv" rating that still has legal porting.

If you are going for speed, there are other things you will want to investigate as well. If you truly just need higher flow (for whatever reason), find the highest Cv legal device.

[Jon Stratis]

Keep in mind that many solenoid only have a max working pressure listed, not a max pressure rating. You may want to contact the manufacturer if you find one you like that is slightly less than 125 psi working pressure - they may be able to provide documentation on a higher max pressure to make it legal without an additional relief valve.

[Qbot2640]

We used this one last season:
http://www.mcmaster.com/#6124K512

for our ball shooter. It was something on the order of five to seven times the flow rate of our previous valves...and worked amazingly well. Got them in one day, if memory serves.

We used 12v with a spike...but they appear to be available in 24v as well.

[jojoguy10]

We used this one last season:
http://www.mcmaster.com/#6124K512

for our ball shooter. It was something on the order of five to seven times the flow rate of our previous valves...and worked amazingly well. Got them in one day, if memory serves.

We used 12v with a spike...but they appear to be available in 24v as well.

Is that solenoid a direct connection for wiring? Or is there a special plug/adapter (like the festos)?

[Qbot2640]

Is that solenoid a direct connection for wiring? Or is there a special plug/adapter (like the festos)?

It has a "plug" that is kind-of attached...but you can remove it and access the wire terminals directly. That's how we used it. Can't remember if they were screw terminals or blades...I think they were blades.

[3a11]

If you are going for speed, there are other things you will want to investigate as well. If you truly just need higher flow (for whatever reason), find the highest Cv legal device.

I suppose we were wrong in assuming flow rate is the end-all-be-allfor speed. What other things should we be investigating? Oh and thanks for the link Qbot2640! And of course see you on Archimedes 503

[FrankJ]

I suppose we were wrong in assuming flow rate is the end-all-be-allfor speed. What other things should we be investigating? Oh and thanks for the link Qbot2640! And of course see you on Archimedes 503

Keep all your tubing runs as short as possible to minimize pressure drops. Optimize the cylinder diameter. Larger cylinder gives you more force but more air flow to move the cylinder quickly.

[mman1506]

368 in 2014 used these fittings (http://www.mcmaster.com/#5203k943/=ws37rd) on their pneumatic shooter allowing for 4 1/4in tube runs between the cyclinder and solenoid to increase flow rate

[Qbot2640]

Keep all your tubing runs as short as possible to minimize pressure drops. Optimize the cylinder diameter. Larger cylinder gives you more force but more air flow to move the cylinder quickly.

Yes...This!
We determined that we needed 12" of stroke for the 2014 shooter. We started with a single 1.5" bore cylinder, but needed either higher pressure than the 60# allowed, or more flow than one solenoid would provide to get the distance we needed. Because the pneumatics rules specifically prohibited plumbing multiple solenoids to a single cylinder - we ended up going with three 3/4" cylinders operated together, eacj with one of the above linked solenoids. We also plumbed an individual Clippard accumulator to each solenoid (working pressure) to have an available volume of air very close (in addition to the accumulators we had at storage pressure). I think the tubing length was less than 3" I'm not sure how much of an impact this had, but it was easy to do. When we hit the fire button, the cylinder action sounds like a gunshot.