(Hal 1-49) UMM (Underground Mining Method)

7/26/2019 (Hal 1-49) UMM (Underground Mining Method)

1/64

UNDERGROUND MINING METHODS

Arranged by Muhammad Amin

Not revised yet

Although it and oen!"ut mining are used #hen ra"ti"al$ there many situations#here they "an%t

be used& Steely diing narro# vein #ill rodu"e very little ore by sur'a"e

te"hni(ues& Even though an ore deosit may be large$ and "an initially be mined

su""ess'ully by sur'a"e mining te"hni(ues$ a oint may be more e"onomi"al to use

underground methods&

Underground mining methods are "lassi)ed or distinguished 'rom ea"h other by

the tye o' suort re(uired in the stoe& Suorts re(uired may range 'rom almost

nothing to heavy timbers "ombined #ith ro"* bolts suorted by tailings$ sand$ or

mine #aste ro"*& Even in the strongest ro"*$ large underground oenings #ill "ave

eventually& I' the ore is #ea* and "aves readily$ a system o' stoing is sometimes

used that ta*es advantage o' this #ea*ness& These are "alled "aving system& Mining

methods usually 'all into one or more o' the 'ollo#ing systems+

,& Oen stoes-gohering$ glory!hole$ room and illar$ sublevel&

.& /ut!and !)ll-hori0ontal or 1at ba"*$ rill$ re!suing$ and timbered&

2& Shrin*age&

3& Timbered-s(uare set and stull&

4& /aving-to sli"e$ sublevel "ave$ long!#all$ and blo"* "ave&

5& /ombination methods&

6& Solution and in situ methods o' re"overing minerals&

There is some overla& 7or e8amle$ in a room and!illar system$ timber or stulls

may be re(uired to suort #ea* areas& A stoe may be started as "ut!and!)ll$ but

as the ground gets heavy or #ea*$ timber may be re(uired& /onversely$ the timber

method may be "hanged to "ut!and!)ll i' the #or*ings enter stronger ground&

The general underground systems #ill be des"ribed in the order listed in this

art$ #ith the e8"etion

o' long #all and short #all systems #hi"h are des"ribed a'ter the room!and!illar

system& This is done be"ause in some mines one may be substituted 'or the other&

In some "ases$ ne# mining system be more "ost e9e"tive than those in "urrent use&

7or e8amle$ in a mine #here s(uare!set timber seems to be re(uired$ the less

"ostly to sli"e method or sublevel "ave system may be substituted under "ertain

"onditions&


2/64

GO:HERING

Gohering$ used 're(uently in small mines$ is really not a method$ but "onsists o'

'ollo#ing the high!grade ore #herever it goes& The miner uses only the suort

ne"essary& It is very di;"ult to i"ture this system& Gohering 're(uently harms the

ore body 'or 'urther mining be"ause it "auses 0ones o' #ea*ness in the ore$

arti"ularly so i' some systemi0ed mining method is to be used later&

Gust

a "avity in the earth "ontinually enlarged by mining& Generally there #as very little

system used$ and the miners o'ten #or*ed under large e8osures o' ba"* or roo'&

The si0e o' the "avity #as o'ten e8tended to the oint #here "aving #as started$

and the ro>e"t #as abandoned&


3/64

Source+ Eugene :& :1eider$ Sur'a"e Mining

S=STEMATI/ ROOM!AND!:I


4/64

In the room!and!illar method$ 2B to 5B er"ent o' the "oal or other mineral

remains in the illars a'ter the rooms are mined& To re"over the illars E$ a illar E$ a

is mined by using timber 'or temorary suort and then allo#ing the area to "ave&

Then illars E$ b are mined and the ground is allo#ed to "ave& As illar robbing

rogresses$ the #hole mined!out blo"* o' ground "ave 7& This ro"edure is "alled

retreating mining be"ause a'ter the illar re"overy starts no attemt is made to goba"* into the blo"*& It is allo#ed to "ave and is abandoned&


5/64

Source+ oehler S& Stout$ Mining Methods and E(uiment


6/64

Source+ Ho#ard


7/64

MODERN


8/64

DRUM SHEARER

Drum shearer has t#o "utting #heels that "an be ositioned 'rom the roo' to the

1oor o' "oal& The shearer moves on the tra"*s on the "onveyor 'rame #hile the

#heels "ut and load the "oal on the "onveyor$ 7ig& 4 ,F&

A'ter the drum shearer has gone by a se"tion o' suorts the ositioning

"ylinders are a"tuated$ ushing the 'a"e "onveyor the #idth o' shearer "ut "loser to

the 'a"e& The suorts are moved one at a time a'ter the 'a"e "onveyor is in its ne#

osition&

The "anoy o' one suort is lo#ered slightly 'rom the roo'$ and the ositioning

"ylinder is a"tuated #hi"h ulls the suort to#ard the "onveyor& Chen in osition$

the "anoy is again raised and ressuri0ed against the roo'& The roo' ro"* is allo#ed

to "ave in the sa"e le't va"ant by the suort that #as moved& 7ig& @&


9/64

A& Isometri" vie# o' a modern long #all mining

system


10/64

@& /ross!se"tion through "ho"* line

/& /ross!se"tion through "ho"* line



11/64

Source+ Samuel M& /assidy$ Elements o' :ra"ti"al /oal

mining


12/64


mining


13/64


mining


14/64

SHORT CA


15/64

dust ha0ards and methane "on"entrations&

2& The "ontinuous miners do not have to be trimmed as 'ar 'or the ne8t "ut so more

rodu"tion time

available&

3& Re"overy by short!#all is as good as or better than room!and!illar mining #ith

illar re"overy&

4& :reliminary results sho# the "osts are lo#er and rodu"tion is higher er man

shi't than in

"onventional room!and!illar&

In "omarison to the long!#all method$ the 'ollo#ing advantages aear&

,& It is easier to move and more 1e8ible than the long!#all system&

.& It does not re(uire the e8tensive develoment o' long!#all and "an be more

easily integrated into

"onventional mining&

2& It re(uires less "aitali0ation than the long!#all method&

3& It is not as a9e"ted by rolls$ "lay veins$ et"& as is the long #all method


16/64


17/64


18/64

Source+ oehler S& Stout$ Mining Methods and

E(uiment

UNDERGROUND MINING

@y Thomas 7& Edgar

/oal is normally e8tra"ted by underground mining te"hni(ues #hen the deth o' the

seam is greater than 2BB 'eet& The "oal in the states o' :ennsylvania$ Cest ?irginia$

entu"*y$ Tennessee$ and Illinois is largely mined by this method$ #hi"h is a labour!

intensive means o' e8tra"tion& Underground mining te"hni(ues "an be one o' 'our

di9erent tyes+

,& Room!and!illar

a& /onventional "ut and shoot

b& /ontinuous

.& or means o'

suort& :anels are mined 'rom these entries$ the anels "onsisting o' a series o'

mine!out rooms searated by suorting illars$ giving a "he"*erboard attern as

sho#n in )gure 2!3& The main entries are o'ten suorted by #ooden 'rame

stru"tures$ #hile roo' bolts are used in the anels and in the entries to revent

remature roo' "ollase& Uon "omletion o' a anel$ the illars may also be mined

to a degree "omatible #ith sa'ety and subsiden"e restrains& Although "omlete

illar removal 'rom a anel is obviously desirable 'rom a materials re"overy oint o'

vie#$ in ra"ti"e only about 4B J to 5B J o' the total "oal in la"e is a"tually

re"overed&

/ON?ENSIONA< ROOM!AND!:I


19/64

shuttle "ar tyi"ally about 4 to 6 ton er load$ #hi"h travels to a dis"harge oint

#here "oal is unloaded onto a rail "ar or belt "onveyor&

/ONTINUOUS ROOM!AND!:I


20/64


21/64

7igure 2!3& The "onventional and "ontinuous methods o' room!and!

illar under!

ground "oal mining


22/64

Source+ Thomas 7& Edgar$ /oal :ro"essing and :ollution

/ontrol

Source+ Thomas 7& Edgar$ /oal :ro"essing and :ollution

/ontrol


23/64


24/64


25/64


26/64


27/64


28/64


29/64


E(uiment


30/64

Removing ore 'rom a 1at!lying stoe by slushers ulling ore to a "hute "an be seen

on :late 4!,F&


31/64


32/64


E(uiment

SHRINAGE STO:ES

The shrin*age method "an be emloyed in steely diing vein i' the ore and

#alls are strong and sel' suorting& @ro*en ore is le't in the stoe to rovide a

#or*ing 1at 'orm 'or the miners& @e"ause brea*ing the ore in"reases its volume by

3B er"ent or more$ some ore must be ulled out o' the stoe as mining rogresses$

other #ise the bro*en ore #ould "ho*e the stoe&

A//ESS TO STO:ES

At ea"h end o' the lanned stoe$ raises are driven trough to the level above A$

and small dri'ts are driven at about .B!'oot intervals to rovide a""ess to the stoe

as mining rogresses u#ard& This stoe is being develoed #ith "hutes at the

mouth o' dra# holes& Not all shrin* stoes are develoed in this 'ashion& Timbered

or "ribbed raises at ea"h end o' the stoe may be used instead o' unsuorted

raises$ and the short dri'ts are not driven& To gain a""ess to the stoe$ the sides o'

the raise are removed& I' raises are not driven trough )rst$ they must be "arried u

#ith the stoe& The stoe sho#n in @ is 'ully develoed e8"et that the "hute raises

are not yet "oned or 'unnelled out&

A'ter the "hute raises are 'unnelled out$ mining is started !and rogresses ba"*

and 'orth a"ross the stoe D& Air!leg drills are "ommonly used in these stoes$ and a

ben"h as mu"h as 15 feetin length "an be drilled and blasted in one shi't& The

series o' ben"hes a"ross the stoe ma*es one verti"al "ut in the stoes& In utting

bro*en ore a#ay 'rom the solid ore 'a"e to rovide #or*ing room$ "aution must be

e8er"ised not to ull too mu"h$ or the miners "annot rea"h the #or*ing 'a"e& Chen

the stoe is "omletely mined out E$ it is 'ull o' bro*en ore$ #hi"h is then removed 7&

/ommonly a illar is le't near ea"h level so that the dri't #ill not be destroyed& The

stoe may be )lled #ith #aste at some later time& The illars may or may not be

re"overed& The shrin*age mine method also s*et"hed at )gure 5!5&

HIGH :RODU/TION :ER MAN SHI7T

The shrin*age method gives a large rodu"tion er man shi't be"ause s"aling$

drilling$ and blasting are the main oerations the ore in the stoe must be "are'ully

dra#n to avoid losing time by under ulling or over ulling&" big disad#antage is

that a large of mined ore must remain amount in the stope until is completed.


33/64


34/64



35/64

Source+ Cilliam /& :etters$ E8loration Mining and Geology


36/64


37/64


E(uiment


38/64


39/64


40/64



41/64

Source+ Cilliam /& :etters$ E8loration Mining and Geology


42/64


43/64

RI


44/64


45/64


46/64


47/64


48/64

HORIONTAority o' mining methods either mine u#ard on the ore body "alled

overhand stoing$ or hori0ontally$ sometimes "alled breast stoing& In theunderhand system mining is "arried on 'rom the to do#n as sho#n in A& The

reason 'or doing this is to have some *ind o' arti)"ial ba"* or roo' suort o' *no#n

strength "hara"teristi"s so ersonnel #ill not be e8osed to overhead #ea* ore and

#all ro"*& The to sli"e method e8lained in :late !.B is an e8amle o' underhand

stoing&

In some mining situations the ore and #all ro"* be"ome so 'ra"tured and loose

they "ave&

These "aves sometimes are di;"ult to "ontrol$ as #ell as being "ostly and time

"onsuming& The "aves at times are so un"ontrollable that mining is abandoned in

the area& This$ un'ortunately$ leaves a valuable resour"e in the ground$ #ith little

"han"e 'or re"overy&

:illar re"overy o'ten is a roblem #hen a ma>or art o' the ore has been removed

by some other method& 7re(uently the illar be"omes bro*en and unstable$ and

overhand methods haven%t al#ays been su""ess'ul l even #ith timbered methods&

/EMENTED SAND7I


51/64

To "ut do#n on the amount o' timber re(uired$ and to rovide a better overhead

stru"ture in re"ent years$ "emented sand!)ll has o'ten been used& 7or narro# veins$

u to t#elve 'eet #ide$ the system sho#n in @ has been su""ess'ully used& A"tually$

it is similar to the hori0ontal "ut!and!)ll te"hni(ue$ e8"et that a'ter the "ut has

been "omleted$ heavy "as or stulls are la"ed on the 1oor or the "leaned out "ut&

They are #edged and inned )rmly in la"e& /ommonly a 'oot o' unbro*en ore isle't on to o' the "ut as sho#n in @ to rote"t the timber #hen the solid ore belo# is

blasted& These may be 'rom three to eight 'eet aart$ but usually 4 'eet&


52/64


53/64



54/64

TO:! S


55/64


56/64


57/64


E(uiment

SU@


58/64


59/64


60/64


E(uiment

SU@


61/64

NUM@ER O7 :ATTERNS @


62/64


63/64


64/64


E(uiment

Documents

(Hal 1-49) UMM (Underground Mining Method)