What happens when you weld on a sodium filled exhaust valve

[dino1]

Have some scrap metal I'd like to turn into "stuff". Have quite a few valves and was wondering what would happen if I went to welding or heating up an exhaust valve that had sodium inside??? Thanks for the help and sorry for the oddball ?

[FusionKing]

I doubt it would be a very smart thing to do. Better you than me

[2much2do]

Being an ex-mechanic, I'm gonna say throw it away. I can't remember exactly what the deal is as I haven't messed with them, but in training we were told anything like that wa bad news. Don't exactly remember what the problem was as it was a long time ago.

[walker]

If you are going to weld on one, just suspend it above a bowl of buttered popcorn, that way any rupture will be contained, and edible!
Truth be told, I can't see any reason not to, using proper ppe's etc. Sodium is not like mercury vapor or anything, and if all you are doing is joining the valve to somthing else I can't see it butning through to thecore of the valve anyway. Also, exhaust valves get pretty hot anyway, I can't see the sodium in the expaning dangerously when you weld it.

[tacmig]

Whoooaa.

Just a moment here, there are many types of sodium i.e. sodium chloride, sodium sulfate, sodium cyanide and even metal sodium and pressurized sodium vapor. All are bad news! Ehhh, I wouldn't put heat to that thing!

TacMig

[Steve]

Hmmm. This is a maybe thing, but just throw out a thought, don't heat it up any hotter than the exhaust gases would. After all, the sodium, is in there to take the heat away. There are liquid sodium cooled nuclear reactors at around 2k degrees. Warning: Random thoughts not to be paid any attention.

[Anti-GMAW]

Hmmm. This is a maybe thing, but just throw out a thought, don't heat it up any hotter than the exhaust gases would. After all, the sodium, is in there to take the heat away. There are liquid sodium cooled nuclear reactors at around 2k degrees. Warning: Random thoughts not to be paid any attention.

Yep, and there also extremly lethal if they burst. The molten hot radioactive sodium is more lethal than the radiation itself. The only safe sodium compound is sodium chloride (ie. salt), other than that i'd say an awful lot of ppe gear. Personaly when it comes to chemicals that are as volital as sodium I'd rather try to avoid it, but if you must then figure out what kind of sodium it is then use the proper safty gear for the given hazards.

[gatkeper1]

427 Ford sodium filled exhaust valves?
The sodium is only in the stems.
Considering how hot the exhaust gases are on a 427 at 7500+ rpm I would not really worry about it too much. Those valves probably glowed while in use and I never heard of any sodium events. The only place that those valves can do any real damage is being installed in an engine. They were known for popping their heads off at inopportune times.
I would venture to say you can weld on them. Play it safe and don't weld in the middle of the stem, thats where the sodium is.
BTW They might bring a few buck on ebay from collectors

[2much2do]

If it were me, I wouldn't screw with it. I'd just find another used valve somewhere. But if you insist, Just don't weld the stem! But for the record, I wouldn't do it at all.

[Steve]

Hey , If you must use them , how about getting the valve guide, slide it on the valve, and tack the end? You could then weld the guide to anything maybe?

[KBar]

Dino

After reading this web site on sodium filled valves. I would not want to touch them with a torch or any kind of weld. This site gives you all the technical data and how quickly it boils inside the valve.

http://periodictable.com/Elements/011/index.html

[Laiky]

I seem to remember from A&P school that the sodium will spontaneously combust on contacting air (O2?). I can remember our teachers telling us (WW2 old timers!) they used to throw them in the ocean so no one would accidentally open one up. Can't swear to it, since its been almost 20 years but that is what i remember.

[Laiky]

found this online, sounds familiar:
Handling Sodium Filled Hollow Valves
The machining and cutting open of sodium-filled hollow valves requires the appropriate caution. Special attention must be given to ensure that the cavity is not opened inadvertently, as sodium reacts violently to water or drilling and grinding emulsions. When sodium reacts to water, oxygen and sodium hydroxide are produced.

Examination and Disposal
Hollow valves is small quantities can be scrapped in the normal manner. There are no special instructions to follow. If sodium-filled valves have to be examined or disposed of in larger quantities, the cavities should be opened, either by drilling holes in two places without using a coolant, or by splitting the valve open in the middle. Valves prepared in this manner are to be placed in a bucket filled with water to neutralise the noxious effect of the sodium. After the chemical reaction has run its course, the valve can be scrapped in the customary manner. The sodium hydroxide is to the respective local regulations.

Safety instructions
Because of the violent chemical reaction and the release of hydrogen when sodium reacts with water, the valves should be neutralised only in well ventilated rooms or out of doors. Contact with the skin and eyes is to be avoided in any case. Sodium should therefore be handled only by properly trained staff wearing the appropriate protective clothing (gloves, goggles, etc.). The customary safety regulations governing the handling of abrasive and caustic material and explosive gases are to be observed.