What is nitrous oxide used for in welding?

[Wade Lippman]

I googled and didn't come up with anything. Presumable it is an oxidizing agent, but why is it used rather than oxygen?

A guy killed himself locally by taking a bunch of medications and then breathing in nitrous oxide he bought from a welding supply house. That made me curious what it is used for.

[Bruce Page]

Some info from Mr. Google:

"Nitrous oxide is used by doctors, ambulance companies, dentists, and vets as an analgesic property. Nitrous oxide is known as laughing gas or sweet air. At room temperature, it is a colorless non-flammable gas, with a slightly sweet odor and taste. Agriculture is the main source of human-produced nitrous oxide. It is also used in cars to increase speed, sometimes called racing oxide. Nitrous oxide and gasoline as possible propellants for a liquid-fueled rocket. The gas is approved for use as a food additive (also known as E942), specifically as an aerosol spray propellant. For example: filling in chip bags, cooking sprays and whipped cream. Regulated by the Food and Drug Administration under the Food Drug and Cosmetics Act."

[Steve Rozmiarek]

It's not used for welding, at least that I've ever heard of. Like Bruce posted, it's an oxidizer, I guess it could be used instead of oxygen in a torch, but not a normal use.

[Rich Engelhardt]

What is nitrous oxide used for in welding?Welding supply places also carry a wide assortment of different gasses that they sell to other customers - such as industrial &/or medical.

Here's the web site to the one that's just down the road from me:

http://www.akronweldsupply.com/7401.html

You can see that they carry some gasses not used for welding.

[Wade Lippman]

Well that explains why I couldn't find anything on it. Thanks.

[Dave Sheldrake]

It's also a food safe propellant in stuff like aerosol creams and creamers. (abused as "Crackers" and often used by one well known author)

cheers

Dave

[Brian Elfert]

Nitrous Oxide that isn't prescribed for medical use is supposed to be poisoned with something that makes people sick if they huff it. I thought they use nitrogen in chip bags, not nitrous oxide? Don't they want to remove the oxygen from chip bags to prevent spoilage?

[Robert LaPlaca]

I googled and didn't come up with anything. Presumable it is an oxidizing agent, but why is it used rather than oxygen?

I don't know about NOS welding uses, but it's seriously used by hot rodding community.. NOS is a serious oxidizing agent, plus it has the added benefit of being endothermic, quotes of horse power increases of 150-120 HP are not unusual..

[Dan Hintz]

I don't know about NOS welding uses, but it's seriously used by hot rodding community.. NOS is a serious oxidizing agent, plus it has the added benefit of being endothermic, quotes of horse power increases of 150-120 HP are not unusual..

I think you're confusing it with the creation of Nitric Oxide, which is endothermic... Nitrous Oxide, when used as an oxidizing agent, is exothermic (hence the extra bang).

[Steve Rozmiarek]

I don't know about NOS welding uses, but it's seriously used by hot rodding community.. NOS is a serious oxidizing agent, plus it has the added benefit of being endothermic, quotes of horse power increases of 150-120 HP are not unusual..

I can vouch for it having profound effects on engines. A higher horsepower setup requires lots of extra fuel to be added too, but the increase in HP can be more like 1000+ on some engines.

[Matt Meiser]

Yep, the welding supply place I use is owned by or owns, not sure the exact structure, a home medical equipment company.

I once saw it propel the fiberglass hood of a 5.0L Mustang at LEAST 100' in the air at a dragstrip. Pretty awesome sight, but not in a good way for the car owner. He was picking up chunks of his intake manifold.

[Dave Richards]

NOS refers to nirtous oxide systems used with engines. It isn't the gas itself. Nitrous Oxide is N2O. I have to deal with it nearly every day at work.

[Erik Loza]

Interestingly, N20 used in the motorsports industry is spiked with butane or some other sort of odorized gas specifically to prevent people from huffing it. I think you have to go to your dentist for the medical grade stuff, LOL.

Erik Loza
Minimax USA

[Wade Lippman]

Interestingly, N20 used in the motorsports industry is spiked with butane or some other sort of odorized gas specifically to prevent people from huffing it. I think you have to go to your dentist for the medical grade stuff, LOL.

Erik Loza
Minimax USA

He was a doctor, so maybe he wrote himself a prescription.

[Ryan Mooney]

N.O.S. in welding gas can also mean Not Otherwise Specified or generic gas mix.

[Dave Sheldrake]

No restrictions here on buying medical grade N2O (like many chemicals) restrictions on selling it but very few on buying. Non food grade such as automotive use is tainted with Sulphur Dioxide, food grade such as 8grm chargers are 99.96% pure.

I have a poisons licence though for stuff like Cyanide that is used for copper plating.

cheers

Dave

[Robert LaPlaca]

I think you're confusing it with the creation of Nitric Oxide, which is endothermic... Nitrous Oxide, when used as an oxidizing agent, is exothermic (hence the extra bang).

No, no confusion here Dan..

Here is a a quote from Wikipedia.. "In vehicle racing (http://en.wikipedia.org/wiki/Racing), nitrous oxide (often referred to as just "nitrous (http://en.wikipedia.org/wiki/Nitrous)") allows the engine to burn more fuel by providing more oxygen than air alone, resulting in a more powerful combustion. The gas itself is not flammable at a low pressure/temperature, but it delivers more oxygen (http://en.wikipedia.org/wiki/Oxygen) than atmospheric air by breaking down at elevated temperatures. Therefore, it is often mixed with another fuel that is easier to deflagrate. Nitrous oxide is stored as a compressed liquid; the evaporation (http://en.wikipedia.org/wiki/Heat_of_vaporisation) and expansion of liquid nitrous oxide in the intake manifold (http://en.wikipedia.org/wiki/Intake_manifold) causes a large drop in intake charge temperature, resulting in a denser charge, further allowing more air/fuel mixture to enter the cylinder. Nitrous oxide is sometimes injected into (or prior to) the intake manifold, whereas other systems directly inject right before the cylinder (direct port injection) to increase power"

[Eric DeSilva]

food grade such as 8grm chargers are 99.96% pure.

I was about to say... I buy nitrous all the time to make whipped cream with my iSi charger. http://www.amazon.com/iSi-N2O-Cream-Chargers-24-Pack/dp/B00007JXR4/ref=sr_1_1?ie=UTF8&qid=1400268785&sr=8-1&keywords=isi

[Myk Rian]

Nitrous oxide is sometimes injected into (or prior to) the intake manifold, whereas other systems directly inject right before the cylinder (direct port injection) to increase power"
What it doesn't say is more gasoline must also be injected. Without that the engine runs extremely lean, and will self-destruct.
Former next-door-neighbor put a 500hp 383 stroker in his Z-28 Camaro. Also had a 500 shot of Nitrous added to it. Awesome car.

[Ryan Mooney]

No, no confusion here Dan..

Here is a a quote from Wikipedia.. "In vehicle racing (http://en.wikipedia.org/wiki/Racing), nitrous oxide (often referred to as just "nitrous (http://en.wikipedia.org/wiki/Nitrous)") allows the engine to burn more fuel by providing more oxygen than air alone, resulting in a more powerful combustion. The gas itself is not flammable at a low pressure/temperature, but it delivers more oxygen (http://en.wikipedia.org/wiki/Oxygen) than atmospheric air by breaking down at elevated temperatures. Therefore, it is often mixed with another fuel that is easier to deflagrate. Nitrous oxide is stored as a compressed liquid; the evaporation (http://en.wikipedia.org/wiki/Heat_of_vaporisation) and expansion of liquid nitrous oxide in the intake manifold (http://en.wikipedia.org/wiki/Intake_manifold) causes a large drop in intake charge temperature, resulting in a denser charge, further allowing more air/fuel mixture to enter the cylinder. Nitrous oxide is sometimes injected into (or prior to) the intake manifold, whereas other systems directly inject right before the cylinder (direct port injection) to increase power"

I believe that Dan was commenting that nitric oxide is in fact sometimes used as part of a welding gas mix (although not entirely because its endothermic but because its a reducing gas).

[Dan Hintz]

I believe that Dan was commenting that nitric oxide is in fact sometimes used as part of a welding gas mix (although not entirely because its endothermic but because its a reducing gas).

Correct, and here's a quote from the American Welding Society:

The addition of nitric oxide (NO) to shielding gases reduces ozone emissions in the welding zone. This technology was first developed by AGA Gas, Inc., in an effort to reduce the ozone in the welder's atmosphere. The name MISON was attached to this family of NO-containing gases produced by AGA Gas. Reduction of ozone can significantly enhance the quality of the welding environment and reduce the incidence of mucous irritation. There are also possible beneficial effects on concentration, productivity, and consistency in welding quality. When trials were done with this gas, it was discovered NO also served to stabilize the arc to good effect when welding high-alloyed stainless steels and aluminum.

...but I'm not sure what I was thinking earlier as nitrous is also endothermic, so my apologies for any confusion.