Oxyfuel flashback arrestors?

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FliesLikeABrick

Wastestream salvage addict
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Hi all,

I am looking into purchasing my first oxyfuel setup. After reviewing some past threads, the message about safety considerations of buying decent equipment have landed well with me (Versus starting with cheap import or unknown history/abused used equipment).

One of the threads recommended the Victor Journeyman setup, I believe referring to https://www.northerntool.com/shop/tools/product_200934228_200934228 (along with multiple folks seconding Victor as a solid brand that some had decades of experience with)

When it mentions "(1) Set of built-in flashback arrestors" -- what are these integrated into? If not integrated, where are these normally located?

Follow-up questions may continue once I'm given a bit of background and direction that I seem to be missing.
 
Built into the torch where the gas lines connect, I believe. I understood that to be where they go if added separately.
 
They are in the Y looking portion of the handle just downstream of the valves.
 
Thanks. So if these weren't built in, they would be separate items attached in-line between the hoses and the torch?
 
Gotcha thanks. On a set like the Journeyman 450, I see the way they're marketed with the max cutting+welding capacities (with the right tips and pressures, of course). Is there a practical lower limit I would expect to be able to braze/weld with this? Not talking "jewelers" small, but open to input on sizing. I have not done any gas welding but do have brazing, cutting, and general heating needs on the horizon where map will not cut it
 
With a #000 welding/brazing tip you can do some pretty fine work. Not sure if they make a #0000 tip, but that would be tiny.
 
For oh so many years, flashback arrestors were not even thought of; the torch popped back, oh well, no damage was done, still I suppose damage might have been done, possibly to the regulators, but finally someone thought to design the arrestors; I've been welding of at least 60 year without arrestors, and the welding world did not end ---
 
Likewise, back when I was an apprentice, 1960 to 1966, we didn't have any flashback arrestors, even though we had many oxy acetylene sets. Torches often popped back, but I don't recall any one actually being hurt, or equipment being damaged.

I have owned two oxy sets over the last 50+ years and it wasn't until I got the second one during the 80's that it came with arrestors, they were not included inside the torch, but were like a little barrel union fitting that was fitted between the torch and the hoses.

Also many of the ships I have worked on had oxy sets and it was not until around the 80's that we got supplied with the arrestors. And yet I've never heard of any accident or anyone being hurt.

I suppose it's technically possible for a flashback to be dangerous, but in the absense of any actual event, how likely is it?

The torch will still pop back, so can not notice any difference in performance or function.
 
All modern torches have flashback arrestors or combination back-flow preventers. The Victor torches have integrated ones, and the Miller-Smith have add-on ones provided in the kit. They are a good idea to have, although acetylene is more dangerous in regards to flashback, since the burn velocity is greater and acetylene can self-react in its hose. Even oxy-propane can benefit, since even though propane cannot flash back, there can be dangerous back flow conditions in which oxygen can get into the propane hose and then flash back. I have a friend who is an EMT and he saw two people die from a torch accident. He suspected flashback.or oil in the oxygen regulator.

I have pretty much only used old torches without the modern safety attachments. There is a procedure to improve one's odds. Soap the torches, valves and connections with an oxygen safe mixture and resolve even small leaks. Keep the tip clean. If there are any pops, find out immediately why they are happening. Do not just relight the torch and go on. Typical reasons are insufficient gas flow for cooling the tip, dirt in the tip, or too close of a work spacing. Any strange noises, especially whistling, means immediately turn off the torch and find out what is going on. Dirty metal, sparks or bb's flying around are to be avoided, since if any of that stuff gets in the orifice, it can cause a dangerous backflow condition that might prove difficult to react to quickly enough. I am sensitive enough to gas prices so that I set everything up very carefully and do not run the torch long enough to get it very hot. I was at a blacksmith demo where the team was running a large rosebud on a manifolded system. It suddenly exploded and it ended up like one of those cartoon exploding cigars. It was fortunate that nobody got hurt, since there were a lot of metal pieces in the air. Somebody dug up the receipt for the tip, and it was a propylene or MAPP tip, and they were feeding it acetylene. Nobody thought to check until after the incident.
 
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