Iron Miners
It is currently Fri Nov 24, 2017 3:27 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 29 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Anthracite Roof Control
PostPosted: Thu Sep 25, 2008 9:38 pm 
Offline
User avatar

Joined: Tue Sep 16, 2008 6:51 pm
Posts: 1423
Location: SW Indiana
In one post Mike A commented / implied that he wouldn't work under roof blots.

So, if anthracite mines don't use roof bolts do they do any type of roof control beside timber? I have read Bituminous Roof Control Plans and what seems normal is bolting on a 5'x 5' pattern . And never working unbolted roof.

Here in the midwest the roof shales are not that stable or consolidated. Is it safe to assume anthracite has a more solid roof geology?


Top
 Profile  
 
 Post subject:
PostPosted: Thu Sep 25, 2008 10:02 pm 
Offline
User avatar

Joined: Mon Jul 09, 2007 5:11 pm
Posts: 899
Location: NEPA
Around here (Anthracite) you don't see roof bolts much except in Kimmels and Harmony which use them. The rest of our mines use timber almost exclusivley. In some cases you have really good top and other times not so good. Remember one thing though, here they veins of coal usually have heavy pitch. In most cases in the chamber or breast all you need is a single piece timber set and your fine. As a matter of fact all you need on most gangways is a single piece and lagging and your perfectly safe.

_________________
"We don't look for any money all we look for is a little help and the only help we get is for the government to shut us down and if you go to the gas station and buy the gas you'll see why..........................you'll see why"


Top
 Profile  
 
 Post subject:
PostPosted: Thu Sep 25, 2008 10:08 pm 
Offline
User avatar

Joined: Fri Jul 08, 2005 12:41 pm
Posts: 2927
Location: Hard coal region, PA
i havn't been in enough bitty mines to know much about their strata, but the anthracite mines that are mining bituminous style have roof control plans consisting of bolting patterns just like you mentioned. its an advantage to have roof bolts in a mine where theres a lot of machinery running around because timber would get in the way. in pitch mining, however, roof bolts are not only unnecessary, but unpractical. of the 12 active mines, 8-9 are working pretty good pitch. You don't only use the timber as roof support, but also as supports for plank to climb up the pitch. the pitch is too heavy to walk up, and you actually have to climb the props in a lot of cases. (remember, your props in a heavy pitch mine are closer to horizontal than vertical). You can't use roof bolts to help you up the pitch! Not only that, but the props also provide a structure to build your coal chute with to feed the coal back down to your gangway.

roof bolts just down make sense in a pitch mine.
plus i don't like them because they don't give you any early warning....you cant really see or hear a bolt taking weight. I personally don't like roof bolts except for maybe helping secure a slab of top in a gangway where timber would be in the way of the buggy.


Top
 Profile  
 
 Post subject:
PostPosted: Thu Sep 25, 2008 11:11 pm 
Offline
User avatar

Joined: Tue Sep 16, 2008 6:51 pm
Posts: 1423
Location: SW Indiana
I guess I don't have the thought process going yet. I had not given the pitch any thougth. And Banks I see what you mean about the props being more horozontial in pitch greater than 45 degrees.

Let's see if I have the terms correct:

Gangway is a main passage

Chamber/Breast ? I assume chamber is the working face.

So, what is the spacing on timbers? And when do you use single vs cross timber and Uprights on the sides?


Top
 Profile  
 
 Post subject:
PostPosted: Thu Sep 25, 2008 11:58 pm 
Offline
User avatar

Joined: Fri Jul 08, 2005 12:41 pm
Posts: 2927
Location: Hard coal region, PA
Right, the gangway is your main haulage way... rail haulage in the heavy pitch. here's a gangway with a coal chute sticking out... notice the rails in the bottom.

Image
Image

The breast is the working face, and the chamber leads to the breast from the gangway. Heres a good example of reaching the first monkey (crosscut) up from the gangway in heavy pitch (low coal). Notice the prop!

Image
Image


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 12:19 am 
Offline
User avatar

Joined: Fri Jul 08, 2005 12:41 pm
Posts: 2927
Location: Hard coal region, PA
So, what is the spacing on timbers? And when do you use single vs cross timber and Uprights on the sides?

The spacing is different than roof bolting.... its generally farther apart. We're not trying to create a solid pillar of rock over our heads like roof bolts do.... just more to support possible loose stuff and have good warning of impending doom.

The "cross timber" we generally only use driving through coal going through the vein. we call them 3 piece sets. two legs and a collar on top. For example, because the veins lay pitched, when you drive a rock tunnel into the side of a mtn, you'll hit a bunch of them. when you drive through a vein, you're gunna have coal on top, be standing on coal, and coal on both ribs..... thats where the three piece sets come in with plank laying across the top of them and plank on the ribs for total roof and rib support.

i wish i had a good photo of the explanation board at the Pioneer Tunnel mine tour... thats the best example of this...


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 2:12 am 
Offline
User avatar

Joined: Mon May 08, 2006 2:16 pm
Posts: 1501
Location: Central Ohio
Oh here we go again anty mines vs. Bituminous. Mike A we are going to drag you out here and get you in some real mines WITH ROOF BOLTS :D .

Doug honestly the best way to understand an Anty mine is really to just go in one. We were trying to figure it out but the most simple way is take one of our mines tilt it up 65 degrees. Most of the veins not seams are between 4ft to 7 ft thick. Gravity does most of the work unless you are that special guy that gets stuck tapping coal. Lift the board up & watch the coal slide by. One important thing to keep in mind Doug not slamming the Anty mines but the methods used are completely different & the tonnage production is not a comparison. They have mined coal like this for decades & it works.

Doug nice shots on the dragline. We are currently on a trip now & saw Big Brutus yesterday in Kansas & today we are hitting the iron & copper mines in Northern Minnesota & Michigan.

Pete, Ohio Vintage Coal

_________________
Pioneering the next INDUSTRIAL REVOLUTION (Preservation ! ). . . Saving equipment (1) mine site at a time.


Last edited by rail haulage miners on Sun Sep 28, 2008 9:21 pm, edited 1 time in total.

Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 6:02 am 
Offline
User avatar

Joined: Mon Jul 09, 2007 5:11 pm
Posts: 899
Location: NEPA
Actually there are plenty of veins bigger than 7 foot. The only ones in the Southern Field that aren't for the most part are the Lykens Valley veins. The Mammoth gets to be more than 100 feet thick in spots. And if you have the right conditions ( fairly thick vein, tunnel, rail haulage) you can Long Hole it and mine just as much coal as a continuous miner can with the same number of men.

_________________
"We don't look for any money all we look for is a little help and the only help we get is for the government to shut us down and if you go to the gas station and buy the gas you'll see why..........................you'll see why"


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 6:44 am 
Offline
User avatar

Joined: Fri Jul 15, 2005 2:34 pm
Posts: 6906
Location: Within 60 Miles of the Northern Anthracite Field
now we have a good discussion going here children dont go ruinin' it with your everlasting battle :lol: timber sets are generally placed on 5 foot centers, unless the coal is very runny, or the top is worse than usual, then they are brought in closer together. ive only seen that in older pictures. all the timber sets we have put in are on 5 foot centers. you are correct, the gangway is driven in the coal vein off, say a rock tunnel between the veins. this is your main transportation road. the breast, or chamber is driven up from the gangway, depending on the mine, but could reach 300 feet before you would sink another level deeper. the monkey is the main return for the air that parallels the gangway about one pillar above it. an anthracite mine tour definitely helps explain this, but we can see what we can do here :D

when i get home from work this afternoon i will link up some images and a diagram that will help understand.

_________________
Come over to the Dark Side....... We have Cookies!


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 5:47 pm 
Offline
User avatar

Joined: Fri Jul 15, 2005 2:34 pm
Posts: 6906
Location: Within 60 Miles of the Northern Anthracite Field
also to keep in mind in setting props up the pitch in the breast like banks mentioned is you use them to climb the chute. you chip out a hitch for them to sit in in the bottom rock, then measure and install the prop tight with the top, with the aid of a wedge or not. these props are not 90 degrees to the top because then they could be easily knocked out or pulled out by falling coal or climbing. so you set the top slightly up pitch so you can pull on them and they not be dislodged.

heres a video put out by the independent miners and associates on building a 3 piece timber set:

http://www.youtube.com/watch?v=K_B3XwyU63o

heres us retimbering an old gangway in the pioneer tunnel mine tour:

http://www.undergroundminers.com/pioneerwork.html

timbering and mine layout images:


Image

Image

Image

_________________
Come over to the Dark Side....... We have Cookies!


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 7:23 pm 
Offline

Joined: Thu Jun 26, 2008 3:39 pm
Posts: 170
Location: West Virginia
Thats pretty interesting. Still give me a joy 14-15 any day. I would like to have some property in this part of VA. I would open me up an anthracite mine.

_________________
_______________________________________ www.pickandshovel.org "For Miners By Miners"


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 7:42 pm 
Offline
User avatar

Joined: Mon Jul 09, 2007 5:11 pm
Posts: 899
Location: NEPA
To each his own I guess, give the boss a case of coalite 8S to take a cut for me to load and I'm happy 8)

_________________
"We don't look for any money all we look for is a little help and the only help we get is for the government to shut us down and if you go to the gas station and buy the gas you'll see why..........................you'll see why"


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 8:26 pm 
Offline
User avatar

Joined: Tue Sep 16, 2008 6:51 pm
Posts: 1423
Location: SW Indiana
Chris and Banks,

Thanks for the information that sheds quite a bit light on the subject. It is hard to comprehend the high pitch and how things have to work. At the extreme angles it seems like it would take considerable effort to keep from sliding back down the chute, let alone working. Essentially it would be like working on a steep roof.

Do you have any pics of drilling at the face? I'm assuming that is all done with air or hand drills.


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 8:30 pm 
Offline
User avatar

Joined: Tue Sep 16, 2008 6:51 pm
Posts: 1423
Location: SW Indiana
Coalfire wrote:
Thats pretty interesting. Still give me a joy 14-15 any day. I would like to have some property in this part of VA. I would open me up an anthracite mine.


I'd like to see you get that Joy up in that chute. But then again, I'd just like to get to see a Continous Miner in person.


Top
 Profile  
 
 Post subject:
PostPosted: Fri Sep 26, 2008 8:32 pm 
Offline
User avatar

Joined: Tue Sep 16, 2008 6:51 pm
Posts: 1423
Location: SW Indiana
Mike A wrote:
To each his own I guess, give the boss a case of coalite 8S to take a cut for me to load and I'm happy 8)



Mike,

Since you brought up the subject. What does a typical shot pattern look like?


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 29 posts ]  Go to page 1, 2  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 7 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group