Forge Explosion!

[BillyBones]

Had my first "pop" yesterday. Well more of a "whump" but it got my attention. I was shutting down and letting my fire settle, sitting enjoying a nice cold adult beverage after a hot day of work kind of day dreaming and got a startle when i heard "whump". Thanks to ya'll and this thread i immediately realized  what had happened. 

Another interesting noise i have had lately is the woodpecker that was on the corner of the roof. Just minding my own and working some hot steel when all of a sudden "tap-tap-tap". Kind of startling when unexpected. He is a red head that only pecked the shop the one time. He comes around mostly to eat the cat food. Amazing how much cat food birds eat, and the groundhog.

[Irondragon Forge ClayWorks]

It's funny in all my years using coal forges, I've never had so much as a whump from any of them.

[ThomasPowers]

My wife used to put out food for the local barn cats; until she figured out that the skunks were coming around to eat it at night.  So no more right before bedtime feedings. Now they get just enough so it's gone before the daylight is.   Having a steel shop woodpeckers are not an issue.  I did have to put chickenwire in the open gables to keep the blasted doves from trying to nest on the trusses.

[bluerooster]

 I had the forge to go "poop" twice today.   Nothing major, just a little "poop" .

[hdvoyager319]

In a Bottom Blast forge, the red hot coals do fall past the Clinker Breaker and accumulate. I would seriously doubt that they will LIGHT an explosion. The fuel for an explosion is coal gas that has backed up below the clinker Breaker and filled the blower and air tube. when the blower is turned, the explosive gas is blown from the bottom into the hot fire--Boom! This can result in the hot fire coals being blown all over the shop and on the blacksmith.

 

The explosion conditions can be eliminated by opening the Trash Gate under the Clinker Breaker. As heat rises, the air feeding from the bottom thru the clinker breaker will keep the fire burning.  NEVER PUT GREEN COAL OR WET COAL ON THE FIRE UNLESS THE BLOWER IS RUNNING! THE FIRE MUST BE ATTENDED ANY TIME THE GREEN COAL OR WET COAL IS ADDED TO THE FIRE.

[hdvoyager319]

Pop just gets your attention. KABOOM!!!!! Gets your attention and a possible disaster. Go back to what you were doing with the fire to determine the cause of the pop.

Many years ago at the Dixon's Gun Makers Fair, the blacksmith from Williamsburg were forging gun barrels out of wrought iron. They would forge weld several inches, bank the fire and forge another several inches an hour or so later. After lunch, we heard a loud BOOM coming from the forge. The forge exploded when the hand crank blower was started. The explosion sprayed hot  coal/coke all over the shop. These blacksmiths were 100% experienced in blacksmithing and how to operate a bottom blast coal forge.

So, with the wrong conditions, your POP could turn into a serious explosion that could burn the shop down and send you to the burn ward.  The little POPs are a warning,.

 

the explosion problem is more serious with a Side Blast Forge because the fire and air system are at the same level. But, coal gas can back up in either the Side Blast or Bottom Blast forge. If you are using bellows, now there is a real potential problem waiting to happen if the coal gas backs up into the bellows. I would guess that Box Bellows that are used with a side blast forge could be very interesting. Hopefully they have a reverse flow check valve.

[George N. M.]

I've had a whomp a few times when I was forging outside and the wind was strong enough and from the right direction that it created back pressure through the fire.  Nothing serious but it caught my attention.

"By hammer and hand all arts do stand."

[ThomasPowers]

I like it when it flashes out the central hole in the side of a hand crank blower.  One reason for mounting double lung bellows in the rafters is to help prevent them from accidentally filling with explosive gas. (Room is another.)