!!! Nitrous Bottle Safety ALERT !!!

[efiguy]

Anyone using a Boondocker Nitrous cylinder, please read the following notice:
Boondocker Safety Alert

Be aware that NOS currently has a safety recall in effect:
NOS Bottle Recall

As a safety reminder for all nitrous users, please remember, do not overfill your bottle, do not overheat your bottle (keep below 120degF), never tamper with the bottle safety blow-off device, and never use a torch to heat your bottle!

note to Admin: could you please make this post a sticky - thanks!

 

[HAMMER]

Dammit...brand new 4lb CF bottle...valve #186281...

 

[stoutner]

Yea, Serial #179933 here.

 

[Blown14psi]

I have N.O.S. brand bottles and I called Holley's tech line and they sent me out new rupture discs and it takes about two seconds to change.

I then asked the tech what the deal was and he said the bad discs rupture at too high pressure and if the bottle gets too hot the bottle could explode. When I got my new ones, guess what?, they are set to rupture at 3000PSI.

At 90 degrees N2O pressure is around 950psi. The onlyway you'll blow a bottle is if you overfill it and leave it outside in the sun when it's 130 degrees out.

Not trying to discourage anyone from getting their bottles repaired, but I don't think it's a big deal especially if you use it on a snowmobile.

 

[efiguy]

Since the carbon fiber bottles have a much higher service pressure rating (3000psi instead of 1800 for Al), they are allowed to use a higher rated burst valve (which is 5/3 the service pressure or 5000psi) so this is less of a concern for them, but the burst disk should still be serviced.

From what I've read on the Holley/NOS recall, 4800psi burst disks were inadvertantly used which is a problem with aluminum bottles since they are rated to burst at a minimum pressure of 4500psi.

One important factor to understand is that nitrous must have room to expand, otherwise the pressure will skyrocket when it heats up. That is why the max fill amount is only 68% the volume of the bottle. I think we figured that if you were to fill a bottle to 95% capacity, it would be possible for it to exceed 3000psi at just below 70degF!

Another danger of overfilling a bottle and having the burst disk blow is that if this were to occur in an enclosed space (like inside a car or small room), the nitrous could cause asphixiation. I believe this is one reason the burst disk is required to be rated to at least a certain amount.

Also it is possible to not overfill a bottle, but still have it exceed 3000psi if it is heated too much - I believe we figured this would occur around 155-160degF for a bottle 68% full.

A proper safety blow-off is an essential part of the design for any pressure vessel (and it is required by law) - you never know when your bottle might accidentally be overfilled, overheated, or involved in a fire.

 

[kinger]

Where is the serial number? My nikel plated valve has the "3000" with no "K" on it but its older then 8/8/06

Here is the website that the bottle manufcture for almost all the bottles are:

http://www.oemregs.com/REH_OEM-RECALL_7-12-07.pdf

 

[efiguy]

Some of the very early bottle valves (bigger & heavier chrome-plated brass) had the knob on the top with no serial number - these are not affected by the recall. The later valves (smaller/lighter and made from aluminum) have the knob on the side and should have a 6-digit serial number marked somewhere on the aluminum body of the valve itself.

The dates and serial numbers Rehvac incuded in their recall are being disputed (we have evidence they do not go back far enough), so to be safe, I would suggest you observe the serial numbers listed in the Boondocker alert.