A Little Too Much Powder Butch?

[D Coots]

Answering Lil Joe and getting away from messing up Bart's post.

Back when I was in the quarry business blasting limestone was part of it. We'd usually shoot 25K tons or so at a time. This particular blast was Bed 12 in my quarry nearby. This ledge was very hard to get breakage towards the top because there was a massive 5 foot bed of rock that broke really hard. We used a pretty tight drill pattern on this ledge. 10"X10' with 4" diameter holes usually about 18' deep. You fill the holes with explosives as high as needed to contain the blast, but still have sufficient breakage so the blasted stone will go through the crusher without plugging it. Out primary crusher would accept a 43" wide rock 38" tall. In a few seconds it would exit the crusher in approximately 5" pieces. We used a water gel on this ledge because there was usually water in the drill holes..i think it was Tovan?? a dupont product. Most blast holes in other ledges we filled to within 8 to 10 feet from the top depending on the laminations. Then we filled the hole to the top with 1" limestone. That's called stemming. Anyhow Bed 12 we filled the holes within 5 feet from the top to get the breakage desired. If the rock was to big to go through the crusher, you incurred costs for secondary breakage which was much more that drilling and shooting. Due to the fact it took about a day and a half to pull the plant and reset it, we blasted with it setting there. You notice the rock blowing way up in the air....but look at the bottom of the shot being blasted...we pushed up a shelf of rock in front to keep the face from blowing out and hitting the plant..(hopefully). There's 2-300 dollars worth of equipment setting there......

My daughter was a professional photographer and just happened to be there that day taking pics for our 50th anniversary celebration. Made a great picture.

Later
Dave

 

[swimster]

Is there limitations on how close explosive mining can be done to a residential area?

 

[D Coots]

Yes. My locations were rural so not bad. We moved my portable plants around Iowa and a few other states custom crushing aggregate for other producers. Crushed rock in Minnesota, Wisconsin, Illinois, and Missouri. Seems like there was 28 loads of mostly oversize/overweight loads to move and set up. Different rules everywhere.

I never set of a blast with out seismographs to cover my AZZ...................

 

[Uthink Uknow]

This was a blast while building a highway in Montana. Paul’s buddy moved there from Michigan. He has a contracting business there. This was a little too much powder.

 

[butchlambert]

I would love to see it! We have folks in our rural area that like to play with tannerite. Nothing like what you are playing with.

 

[D Coots]

I would love to see it! We have folks in our rural area that like to play with tannerite. Nothing like what you are playing with.

Used to play with, is the key word Butch. I used to determine the hole size, pattern, what explosives to use, and load the shot. When I bought the company we started having the powder company do all that. I had to be in the office.

A couple 30 gallon garbage bags full of oxygen and acetylene pulled up in the air on a crane boom, and set off with an electric blasting cap makes a concussion you can feel a hundred yards away they tell me.

 

[DirtySteve]

Seriously there is a coyote under that rock, right. Probably a roadrunner near by..?

 

[butchlambert]

Dave, I have a real fear of heights, but I like a good boom. My Grandfather used dynamite to remove the old native black walnut trees to clear his farm land. In the late 1940s they either had no chainsaws or couldn't afford them. It was cost effective for him. Pa would hold his hands over my ears as my Uncle set off the charge. I loved it.

 

[snert]

Used to play with, is the key word Butch. I used to determine the hole size, pattern, what explosives to use, and load the shot. When I bought the company we started having the powder company do all that. I had to be in the office.

A couple 30 gallon garbage bags full of oxygen and acetylene pulled up in the air on a crane boom, and set off with an electric blasting cap makes a concussion you can feel a hundred yards away they tell me.

A bread bag full of acetylene and oxygen laid on a gravel road and ignited by a dumb cousin in shorts and no shirt with a long pole and a gas lit rag hanging over his shoulder (we might have helped by telling him when to drop it) will clear the road of gravel, break the picture window on the house, bring the police and imbed gravel in the legs and back of said dumb cousin....

Statute of limitations long over.

 

[D Coots]

Probably used those 1x12" sticks Butch. After you handle those for a while you understand about a throbbing nitro headache.....been there, done that. It was great when they went to water gels and you didn't have to handle that old stuff.

 

[butchlambert]

I can relate to the acetylene. My father in law had a carbide generator to drip it into water I think to made his acetylene. He ran his hose straight to it and sometimes he would grab the tank and shake the crap out of it to help it work. It kinda scared me!

 

[joshb]

Oxy-acetylene trash bag fireworks.........ahhhhh.......that takes me back! 1975, I think.

 

[miningshawn]

Nice. I was the blasting engineer for a mine in the Artic Circle. Every shot had to be engineered as our material was ridiculously high SG. We did not worry about scaled distance, there was nobody there to complain. My average shot was 400 holes, 150,000 lbs of emulsion, and around 1500 milliseconds.

It's a fun job for about 10 seconds, it just takes days to get there.

 

[X Count]

Get a good size piece of pipe 6" diameter say 6' long and an oxy set. Light up a neutral flame and snuff out on the bench. . . .let the gas from the neutral mixture run into the pipe for a minute or two. Make sure both ends are clear and light it up. That will blow sheets of iron off your shed and clear pigeons out the rail yard next door.

Residential blasting. I live about 1.5mile from a limestone quarry where dad worked for nearly 40yrs. Got to watch a few blasts and done properly its extremely stable. I Remember getting to stomp on the blasting cap from only a few hundred yards away. But there was one time where the nitropril worked its way into a natural void and launched a rock through the lunchroom roof and bounced off the pie warmer! That's when they decided it was best to evacuate to the boundary instead of just blasting while everyone was out the pit and having lunch!

 

[centerlineseal]

Tovan??

Tovex.

Miss those days. Thanks!

 

[D Coots]

Miningshawn
Wow that is moving material, kind of like cast blasting in surface mines. What kind of material were you working with, nickel-copper? Tell me more. BIG drill holes..

X Count

Blasting is controlled chaos. You may have 10 shots that go perfect, then you run into a clay pocket or a void like you mentioned. If you're using ANFO you need to pay attention to how long it takes to fill the hole. If you're filling a void...that's not good. Also not enough burden in the pattern is not good.

I recall a few incidents over the years. You ALWAYS need something like a dump truck to get under. That's what we usually used. Didn't have a bona-fide blasting shelter. I remember crawling in under that truck as rock's fell from the sky and landed in the box. Gets really noisy.

 

[D Coots]

Tovex.

Miss those days. Thanks!

The tovex we used was a stick...3.5×16"

The tovan was a slurry if I recall correctly.

 

[D Coots]

Who ever said blasting wasn't fun...Hold my beer and watch this.

World's Fastest Buick

 

[ebb]

The primer is the key, was it flat after the blast? Bolt sticky?

 

[ebb]

The landowners or the water district were enlarging a canal in the glades ag district. They had removed earth till they hit rock that went for miles and they needed more volume but wider was not an option. They damned the canal at both ends and pumped it dry then made a road so a drill rig could get in on top of the rock. Then they drilled holes for days and had gone a long way and I kept watching to see if i could watch the blast. but they blasted when i wasn't around. It looked like over a mile went up at one time. I wish I coild have seen it go .