ü o a l A g e
McGraw- Hill
Publishing Co m p a n y, In c. Jam es H . M c G r a w , P resident E d w ard J . M e h r e n , V ice-President
D e v o t e d to the O p e r a tin g , Techn ical and Business P r o b l e m s o f the
C o a l M i n i n g I n d u s tr y Jo h n M . Ca r m o d y
Editor.
V o lttm e 3 3 N e w Yo r k, Ju n e, 1 9 2 8 N u m b e r 6
Who W ill Be N ext?
M A R K T W A I N is credited w ith the shrew d ob servation th at everybody complained o f the w e a th e r but nobody, did anything about it. T h i s m asterly inaction in matters m e teo r o lo g ic a l has had a limping counterpart in the handling o f the problem of overproduction in bituminous coal. Since the war, at least, there has been- general agreement th at d ev elo p ed mine capacity has been fa r in excess o f requirements. But few producers have volun teered to begin the ap
plication o f corrective measures at their own properties.
I T IS this unw illingness which gives the re
cent public announcem ent o f a new policy by the C on solid ation C oal C om pany unusual significance. T h i s announcem ent com mits the company to the b elief th at no perm anent re
lief for the industry can be w o n “by further cutting w a g e s b elo w a sound econom ic le v e l”
or by selling coal at prices which do not yield a fair margin over cost. R e co g n iz in g these facts, the C on solid ation com pany has shut down a number o f its least efficient mines for an indefinite period. It couples this action with an appeal to fe llo w producers to join in the m ovem en t.
T h e implications in volve d in the ad op tion o f this p ro g ra m cannot be over esti
mated. T h e te m p orary closing d ow n o f mines— both efficient and inefficient— w hen a continued dearth o f orders leaves no alterna
tive is not new. Concentration o f operations by interests o w n in g several mines has been resorted to b efore, alth ough not to the ex
tent, perhaps, that it m igh t have been. T h e r e is a note in the C on solid ation announcement, h ow ever, which su ggests a m atured decision setting up a long-time policy rather than a short retreat o f expediency.
E m p h a s i s is placed upon this n o te be
cause the willingness to p le d g e the m an agem en t so publicly to a policy which subordinates ton n age to a sound m erch an dis
ing p ro g ra m marks the trail out o f the economic jungle in which the industry has been stumbling. F o r m ore than a decade bituminous coal has been under legislative and social attack. T h a t it so far has success
fully repelled these assaults cannot disguise the w eakn ess in its d efen se— a w eakness born o f a persistent disinclination o f the in
dustry as a w h o le to grap p le volun tarily with the p roblem o f overproduction.
S I N G L E - H A N D E D n either this com pany n or any oth er larg e prod ucin g unit can rescue the industry fr o m its present plight.
A lo n e th ey conceivably can im p rove t h e ir financial position and conserve their assets by rigid adherence to the policy thus laid down. But the benefits to the industry as a w h o le will come in p rop ortion to the number o f responsible op erators w illin g to m ake their individual contributions and sacrifice to the cause o f stabilization. T h e question n o w is not h o w m an y producers are content to sit on the side lines applauding but h o w m any will actually g et into the gam e. W h o will be next?
To Clip Machine-Loading Costs
Institute Time Studies A nd Daily Reports
F
ROM the days of earliest recorded history, m ethods of anal
ysis have been used to detect the waste in industry. T h e universal form of this analysis is bookkeeping, which from the simple notations of total costs and gross realizations has been developed till now there are thousands of complicated systems of accounting, based upon exact in
formation and carried to a concluding figure, sometimes shown in decimals of cents per unit of accomplishment.
All productive operations need these figures, for they are to m odern busi
ness what the eyes are to the hum an body.
As the production of coal by mod
ern machinery calls for a complete revision of the old operating stand
ards and, particularly, a revision of all underground phases of operation, which, be it said, constitute by fa r the largest part of total costs, indicative machine-performance records are as valuable to the company as an ade
quate system of bookkeeping.
As all forms of “pencil w ork”
were delegated in the past to those non - productive w orkers whose authority did not extend past the mine mouth and as the “check sys
tem relieved the m iner of responsi
bility and served the local m anage
ment as the base from which the greater part of total costs were com
puted, the introduction of daily re
ports covering various phases of underground operations called forth
mjLBLE i n i t i a l t a b u l a t i o n o f m e c h a n ic a l-l o a d e r o p e r a t i o n s
n . M in u te s P e r c e n ta g e
mtnHng~ "w a ^ n g ’ c a r c}ianKe,
P o « r g ' s h lit‘n g . e t c 5,180 77.08
C i 25 0.37
$ k l l
M a S o iiin ,.: H f
M S w T ' ring •‘«ceuaneous 255 100 l 7Q1.50 No c,55ii ?rach'T . - A ■ A ;;; t5 022
coal p re p a re d 230 3.57
6,720 100.00
By W alter M . Dake
Consulting E ngineer Joy M anufacturing Co.,
F ranklin, Pa.
W alter M . Dake
a m ighty protest from those who form erly issued and transm itted v er
bal orders and who never signed any paper other than their pay checks.
B ut with the high investm ent cost of m odern cutting, drilling, loading and haulage units, having potential production efficiencies m any times greater than ever before, the time element in machine use enters the coal industry, as it long ago entered into m anufacturing, and calls for an organized effort to attain the contin
uous operation and complete co
ordination of these machines so that their output per shift may be as large as possible.
W ithout adequate and accurate perform ance records, how can un necessary and therefore costly delays be elim inated? Shall we range opinion against fact, where unpro
ductive time is known to be equiv
alent to wasted dollars and cents?
Though the responsibility for the selection of the particular type of loading machine best adapted to local conditions rests jointly with the m an
agement and the m anufacturer, and though the limits of operating effi
ciency are determ ined jointly by the m ining engineers of both companies, the .underground organizations m ust be held responsible fo r the daily operation and maintenance of the equipment.
In addition, the adequacy of . the preparation of the coal at. the face, of the power and transportation .fac
ilities, of the drainage, ventilation and supply service, of the safety pro
visions and of many other production phases, all have a part in determ ining the final costs.
1 he degree to which items singly or collectively affect mechanical- loader operation cannot be correctly analyzed and judged from observa
tion alone. H ow ever, w ith general report systems which can be used for indicative purposes and with special studies fo r the final analysis of spe-
F O R M A — T I M E C O S T S P E R A V E R A G E M E C H A N I C A L L E A D E R U N I T
0 . 0
n 32 £
E m p lo y e d a s Z
F a c e f o r e m a n ...
C u t t e r s ...
D r ill e r s ...
T a m p e r s ...
S h o tf ir e r s ...
L o a d e r o p e r a t o r ...
L o a d e r h e lp e r ...
M o fco rm an ...
M o to r h e l p e r ...
D r i v e r s ...
T r a c k m a n ...
T r a c k h e lp e r ...
T i m b e r m a n ...
T im b e r h e l p e r ...
S n u b b e r s ...
C le a n - u p m e n ...
T o t a l l a b o r ...
P r o p o r tio n s ... ..
G e n e r a l u n d e r g r o u n d ex p e n s e , d e p r e c ia tio n , e tc.
-2.5cSCQ
A p p r o x im a te c o s ts ... %... $ ... $.
June, 1928 — C O A L A G E 335
F O R M C — T I M E S T U D Y R E P O R T
S h e e t N u m b e r ... D a t e ... 192.
C o m p a n y ... ...
L o c a tio n ...
M c li. T y p e ... M c h . N u m b e r ...
T im e S t a r t e d ... .. • .T i m e F in is h e d ... ...
A v . T o n s p e r C a r ... N o . C a r s L o a d e d ...
J ! . 1 . a I I i l ! J g l I I
" 5 ' 1 Q J ZÔ -S1 ¿j g. g J | § J g g l I I
ź 3 o s 6 « « ä ś a S g ° s ,ss
O
(C o lu m n T o ta l in M in u te s ) (S ig n e d ).
cific problems, highly accurate recom
mendations can be form ulated fo r an increase in operating efficiency.
In considering the value and neces
sity for daily reports, for time studies and fo r perm anent records of me- chanical-loader perform ance it m ust be remembered that hand-loading practice differs from that of machine loading in such an im portant though obvious m anner as to w arran t re
peated mention whenever the two methods are compared.
This difference lies in the fact that with mechanical loaders the labor cost per shift for each crew is pre
determ ined by the day-labor wage rates, whereas with hand loading the m iner is paid a contract wage based on his production.
In order to im press this point upon all those who have anything to do w ith the operation of mechanical loaders it is suggested that a list be prepared for each average operating unit in which would appear the face forem an, cutters, drillers, tam pers, shotfirers, loader operator and helper, m otorm an and helper or drivers, track, tim ber and clean-up men, to gether w ith any other labor necessary to deliver the coal to partings.
A gainst these should be placed their rates of pay per shift and the total labor expenditure. T his should be estim ated per shift, per hour and per minute, so as to show the average cost in dollars for each unit of elapsed tim e during a single shift.
T o this should be added a correct proportion of the investment and general m ine-expense charges. This will show the total cost per elapsed
F O R M B — D E M O N S T R A T O R ’S R E P O R T D a t e ... 1 9 2 . . . . C o m p a n y ...
L o c a ti o n ...
M c h . T y p e . . ...M c h . N u m b e r ...
S h if t S t a r t e d ...F in is h e d ...
T o t a l S h if t T im e , in M i n u te s ...
L e ss L u n c h T im e , in M in u te s ...
T o t a l O p e r a tin g T im e , in M in u te s ...
A v . T o n s p e r C a r T o t a l L o a d e d ...
D e la y s * M in u te s s T o t a l
P o w e r ...
C u t t i n g --- D r ill in g ...
S h o o tin g ...
P r o p s ...
P ic k i n g ...
T r a c k ...
T r a n s p o r t a tio n ..
C a r s ...
M c h . O ilin g ...
M c h . R e p a i r s . . . M ia c ...
N o c o a l...
( N o te A d d itio n a l o r U n u s u a l D e la y s on
B a c k ) T o t a l . . . .
D e m o n s tr a to r M in e S u p e r in t e n d e n t
m inute, hour or loading-machine unit shift. I t will represent the actual dollar output per unit of sh ift time, against which m ust be balanced the actual tonnage produced. A method of tabulating this approxim ate cost per mechanical loader unit is shown as F orm A.
In other words, mechanical-loader unit costs per m inute, at m oments when there is no production, repre
sents direct expenditures per m inute w ithout return. Inversely, low costs are possible only when there is a com
plete co-ordination of all operating phases which will insure a continuous output of product at m axim um unit efficiency.
Beginning with indicative records of loading-unit operation, the demon
strato r’s report, F o rm B, is based on the theory th at while he is operating his machine a mechanical-loader oper
ator cannot note the actual shift-tim e distribution, but th at he can time and note all accidental or avoidable delays which shut the machine down. T h ere
for^, spaces are provided for the entry of m inutes of delay due to power failure, derailm ents, lack of mine cars, failure of transportation, etc.
By recording the starting and finishing tim e of the sh ift and deduct
ing the lunch period the total time available for operation is shown, from which is deducted the time noted as chargeable to accidental or avoidable delays, leaving an estim ated operating tim e covering the necessary phases, such as loading, shifting m a
chine at the face, car change, mov
ing machine from finished to new face, etc.
Though these records do not con
stitute accurate shift-tim e distribu
tion, their com parative percentages for consecutive days or weeks of operation show conclusively the main causes of unnecessary time losses.
F o r instance, consecutive daily re
p o r t s s h o w in g h ig h p e r c e n t a g e s of l o s t ti m e d u e to th e it e m “ P ic k in g ,”
w h ic h r e f e r s to r e l e a s i n g o f tig h t f a c e s b y t h e u s e o f t h e p ic k , w ill p o i n t d i r e c t l y to i m p r o p e r f a c e p re p a r a t i o n , w h ic h m a y b e c a u s e d . by
“ g r i p p e d ” c u t t i n g , b y in c o r r e c t plac
in g o r c h a r g i n g o f d r i ll h o le s o r by la c k o f a s u f fic ie n t n u m b e r o f holes p e r fa c e .
I f e i t h e r o f t h e it e m s “ N o c a r s ” or
“ T r a n s p o r t a t i o n ” s h o w s h ig h p e r
c e n ta g e s o f lo s t tim e t h e c a u s e m ay b e f o u n d in la c k o f m i n e - c a r sto ra g e r o o m n e a r t h e m a c h i n e s , la c k o f co
o r d i n a t i o n o f p r i m a r y a n d s e c o n d a ry h a u la g e , i m p r o p e r t r a c k g a g e o r c u r v e s c a u s i n g c a r d e r a i l m e n t s , etc.
T a b l e I is a t a b u l a t i o n o f d e m o n s t r a t o r s ’ r e p o r t s r e c o r d e d d u r i n g a p e r i o d o f 14 c o n s e c u t iv e d a y s ,, an d w o r k e d o u t f o r in d i c a ti v e p e rc e n ta g e s o f t o t a l s h i f t tim e .
A n a n a ly s is o f t h e f o r e g o i n g table q u ic k l y s h o w s t h a t t h e g r e a t e s t p e r
c e n ta g e o f u n n e c e s s a r y lo s t tim e is c h a r g e a b l e to “ N o c a r s , ” a n d t h a t this
F O R M D — D A I L Y R E P O R T O F S E C T IO N F O R E M A N
D a t e ... M a c h in e N o ...
C a r s L o a d e d ...
T o n s D u m p e d ... ...
C h e c k
E m p lo y e d a s N o . H o u r s C ost
O p e r a t o r . ...
H e lp e r ...
M o to r m e n ...
T r i p r id e r ... ...
T im b e r m e n ...
T r a c k m e n ...
C le a n - u p m e n ...
C u t t e r s ... ...
S n u b b e r s ... . . . ...
D r ill e r s ...
S h o t f i r e r . ...
M is c e lla n e o u s ...
C u t t i n g ... y ...
M a in te n a n c e l a b o r ...
C o s t, p a r t s u s e d ...
L u b r i c a n ts ...1... ^ T o t a l ...
A v e r a g e p e r to n ...
... S e c tio n Forem an ...M in e Forem an
(T u r n to page 372)
336 C O A L A G E — Vol.33, No.6
S h a llm a r’s H eritage From the P a st
Keeps
P r o d u c t i o n C o s t s
Low
By R. Dawson H all
E ngineering E ditor, Coal A g e
O N T IN U IN G the quest for a mine w ith a better record for steady operation than most of those in its field, I came upon the Wolf Den mine, owned by the Shall- mar Mining C orporation, at Shallm ar, Md. Said H . A. M arshall, the su
perintendent, in reply to a question regarding the steadier ru n : “ Yes, we run about four days a week where other mines in the region are running two or less. A num ber of operations have had to drop out entirely. T here were 42 mines in this region where now there are only 13.
“I t’s a hard pace, and probably the only thing that keeps things going as they do is the fact th at from the first the company has had a good, well- considered plan of operation and kept to it. I t m ight have clipped a few corners in the housing of its men, but from principle it has continuously given them considerate treatm ent, which pays in the long run. I t might have gutted its coal; but if it had, after these ten
years of opera
tion, it w o u l d have had badly h e a v e d road
ways, bad bond- 1 n g , squeezes, broken roof in the headings and a l o n g haul.
With a f e w exceptions, a n d then only when retreating t h e gangway stumps, the coal has been taken out clean, the gobbed areas have fallen tight and t h e weight
coal in place, only to make the new w ork m ore rem ote than it need be, m aking more feed w ire necessary, tim ber costs excessive, roads bad and ventilation difficult. The m ain entry at this mine is still w ithin 3.000 ft.
of the d rift mouth. T he th ird pair of panel entries has yet to be started, so the mine though ten years old is still small, still in that sense young, even though the coal is only 4 ft.
thick and the content per acre is not large.
“E verything has been driven to sights. T he main entry has three headings that advance on the butt up a 4\ deg. grade. A t about 250 ft.
from the d rift m outh pairs of head
ings called panel entries have been driven right and left. Those to the left are driven on the face, in which direction they rise, those to the right are driven on the strike, thus m aking less than a right angle w ith the butt entry. A t distances exceed
ing t h e lengths o f tw o rooms, triple-entry butt h e a d i n g s are driven till they meet other panel d o u b l e entries above at a dis
tance o f about 1,250 ft. In two cases, instead of t r i p l e entries double butt en- t r i e s w e r e driven, but th at practice has not has been removed. No squeezes have
occurred in the main and chain en
tries, in which the bulk of the hauling has to be done. W h at squeezes have occurred have been in w ithdraw ing butt-entry stum ps a fte r all the rooms have been finished and pillars drawn.
“T his trouble is now eliminated, for the rooms are driven from the inby outw ard, so that as soon as the rooms are driven and their pil
lars removed the stum ps can be pulled back also. Because of the complete
ness with which the coal has been extracted the m ap hanging in the mine office does not bear evidence to the time the mine has been running.
A m ine map should always belie the age of the operations it records.
“ Too m any mines have been de
veloped in which 30 or 50 per cent of the development has been throw n away by leaving that percentage of
Shallm ar, Gay W ith F orest and Planted Trees
ttme, 1928 — C O A L A G E 337
been followed elsewhere in the mine.
“All the rest of the w ork is just as originally planned. Rooms are driven, on sights, from the butt head
ings, in both directions to meet. In order to avoid downgrades they are not driven at right angles to the face or to the butt headings, but on a grade of about 1 per cent and always on sights. A s the roof is none too good the rooms are driven only 18 ft. wide w ith 30-ft. pillars between them, which is quite conservative and a f
fords assurance at all times that, with the cover existing, it will be possible to draw the room pillars without squeezes.”
A
L L this is not exceptional, with - such companies as the Consolidation Coal Co. or the H . C. F rick Coke Co. or in regions such as the P o cahontas, but the smaller companies usually are not quite so careful and methodical and if they are the plan is likely to go to the winds when times like the present come. B ut this m ine has had but two superintend
ents, Thom as Griffith, who planned and built the plant and died about two years ago, and H ow ard M arshall, who now m anages it. F ortunately, they have never been tempted to gain a few m onths’ advantage at the cost of the fu tu re successful operation of the mine.
“ M r. Griffith tried,” said M r.
M arshall, “to keep the mine in such condition that the unforeseen could not happen. Sometimes the unusual has occurred, however, such as the big cloudburst over the E lk G arden w atershed and the Potom ac in general that nearly swept away, our village and brought houses from up the river tum bling past our works. But, in general, any mine that finds itself facing the unexpected has not been properly laid out or maintained;
In a Clearing A lo n g the Potom ac
“H ere is an experience that may be useful to those who are troubled with low voltage. Some time back I noted that the voltage was low at the end of the line. I did not w ant to lay a feed line if the trouble could be cor
rected without it. I concluded to try to improve the bonding and I put in several cross-bonds. I had the rail bonds examined and where defective replaced, but the resistance in the re
tu rn was not enough th at any im provement in the bonding would greatly increase the voltage.
“Trolley lines ru n into both of th e outside headings of the main entry and by connecting the wire in the left heading with th at in the right at a point well w ithin the mine a distinct im provem ent in the voltage was obtained. H ow ever, as soon as the third panel entries, with some of their butt entries, have pro
gressed a little fu rther, a feed wire W here Shallm ar
Generates I ts P o w er
will be necessary and will be supplied, but the interconnection between the two roads will still be all to the good and will m ake for better voltage. One trolley w ire will act as a feeder for the other. Electrical engineers may regard this cure for low voltage as somewhat obvious but it may not have occurred to everyone having this kind of difficulty.
“T he seam w orked is the Lower K ittanning, or B, and it is split by a middle rock 12 in’, thick, which at times is much thicker. In general, that is tru e of all the Potomac field, but in the southern part, where the Davis Coal & Coke Co. is working, the lower bed is the thinner, whereas in our mine the bottom split is 4 ft.
thick and the upper only 12 in.
“T he headings are driven so that the bottom of the lower split is the floor of the heading and the top of the upper split is the roof. In the rooms, however, it does not pay to remove the m iddle rock, especially as the upper split is not as free from ash as the lower.
“T he removal of the upper split in the headings makes them of good height and gives a better roof than is found in the rooms. Y et the road
ways are kept to a w idth of 10 ft., so that no tim ber may be required.
T his in itself is a great aid to venti
lation and saves a large expenditure fo r timber, though not so much as in some mines because, owing to the excellence of the ventilation, hardly any fungous grow th can he discerned at our mine.
“A t first the headings w ere driven wide in the lower split and 10 ft.
wide in the middle rock and upper split. T he rock from the middle stratum was stowed in the widening of the lower coal bed. B ut this ma-
(T n r n to page 355)
338 C O A L A G E — Vol.33,N o.6
M e c h a n . i z a t i o n
Captures Industry
A t Cincinnati Convention M
e c h a n i c a l loading nolonger is on the defensive.
No longer do practical oper
ating men ask: “ H ow will it be accomplished?” T oday the pioneers in the movement are kept busy telling their fellows how it has been done while the unmechanized find it in
creasingly difficult to dodge a dis- tinctily personal “why aren ’t you doing it.”
Today the doubters are less bold—
because the failures in the application of mechanization to underground loading are so much few er than they were only three short years ago.
Now the advocates of the machine age in handling coal at the face are much more confident and the suc
cesses back of them are much m ore numerous.
Doubts die hard but they found little encouragement to fu rth e r living in the fifth annual convention of practical operating men held under the auspices of the A m erican M ining Congress at the M usic Hall, Cincin- mati, Ohio, M ay 7-11. T h at g ather
ing proved to be a field holiday1 for the proponents of mechanized mining.
The spirit of m echanization captured the meeting and all other discussions seemed to assum e im portance only as they fitted into and became parts of the larger picture.
Beginning w ith the statistical sum mary of w hat has been accomplished m a few years in the way of increas- Hig the tonnage of ■ mechanically loaded coal— from 1,879,726 tons in 1923 to 10,022,195 tons in 1926—
and proceeding through the im pres
sive roll call of states to the more detailed exposition of achievements m mechanized m ining a t individual operations, the record m ade for the machine age was too convincing to give much com fort to those who hold that the old ways necessarily m ust he the best.
The four-day program of the convention, in which mechanization
occupied so large a place, made it plain that the whole burden fo r the success of mechanical loading cannot be placed upon the machine. B etter m anagem ent, better tracks, larger and better cars—all are needed to give the loading machine an increased opportunity to function profitably.
These aids, it is true, w ere needed before, but the introduction of the loading m achine has m ade their em ploym ent imperative.
H ow the m anufacturers o f equip
m ent fo r coal mines are keeping pace w ith the broader requirem ents of the coal mines— requirem ents which, to m ention only one instance, absorbed one-third of all the auto
m atic substations sold to industry at large last year— was shown in the exposition of equipm ent sim ulta
neously held at the M usic H all under the auspices of the m anu factu rers’
division of the Congress. New developments in loading machines, bigger locomotives, im proved screens and fu rth e r refinem ents in accessories w ere on display to help the delegate
H arold A . B u zb y
to the convention visualize the m e
chanical side of the new m achine age.
T he broader problems of m anage
m ent claimed attenton at the opening session of the convention on M ay 7, when H . A. Treadw ell, Chicago, W ilm ington & F ran klin Coal Co., told how the w orld’s largest bitum inous m ine m et the issues of general un
derground supervision, and IT. S.
Gilbertson, Lehigh Coal & N avigation Co., contributed an address on the selection and train in g of personnel.
These addresses, as well as other features of the technical sessions of the convention, are treated at length in the repo rt appearing on pages 341 to 355 of this issue of Coal Age.
New equipm ent developments are covered on pages 361 to 372.
T he cause of rock-dusting was ex
pounded by Charles Enzian, Berw ind- W hite Coal M ining Co., and J. E.
Jon es/O ld Ben Coal C orporation,w ho pointed out th at 97 per cent of the output of F ranklin County, Illinois, came from rock-clusted mines. Daniel H arring ton, U . S. B ureau of M ines, presented the case of safety equip
m ent as an accident preventive, and R ichard D. Maize, Pennsylvania state m ine inspector, discussed the ventila
tion o f gaseous mines.
H aulage systems and power were the topics of the m orning session on M ay 8. In the course of a paper on m ine-car design, C. E . W atts, B erw ind-W hite Coal M ining Co., suggested detailed specifications to put all bidders on an equality, use of copper-content steel and gave com
parative figures on lubrication costs.
R. L. Adams, Old Ben Coal C orpora
tion, gave common practice in haulage in large mines a jolt by advocating the use of gathering locomotives to handle cars from the room entries to the sh aft bottom. T he u nd er
ground transportation system of the Ebensburg Coal Co. was described by R. M. Flem ing.
O ver 150 autom atic pum ping sta-
fune, 192S — C O A L A G E 339
tions in the anthracite region are saving the operators $500,000 an
nually in labor, according to T. J.
Jennings, Philadelphia & R eading Coal & Iron Co. The advantages of autom atic substations w ere treated by W . C. Shunk, Stonega Coke & Coal
Charles C. W haley
Co. Discussion of these tw o papers closed the session.
T he battle of the wets and the drys in coal cleaning began at the a fte r
noon session. D ry cleaning and its advantages w ere presented by Thom as F raser, consulting engineer; E. J.
N ew baker, B erw ind-W hite Coal M in
ing C o.; R. G. P erry, New R iver &
Pocahontas Consolidated Coal Co., and W . J. O ’Toole, Am erican Coal Cleaning Corporation.
T he side of the wets was heard the next morning, when J. B. M or
row, research engineer, P ittsburgh Coal Co., presented a paper outlining the fundam ental factors to be con
sidered in the selection of a cleaning plant. B. C. Osier, Sham okin Coal Co., and G. P . Bartholomew, A m er
ican Sm elting & Refining Co., de
scribed R heolaveur installations, and Thom as F. Steele, South P en n Col
lieries Co., a Chance cleaning plant.
•Developments in cleaning in the past fifty years w ere reviewed by Eli T.
Conner and Col. E dw ard O ’Toole.
Discussion of m echanization proper began at the afternoon session on M ay 9 and continued through the two sessions held on the following day. P robably the most dram atic feature of these sessions was the roll call o f progress by states. . A s is shown in the tabulation appearing on this page, while the progress is spotty, some notew orthy gains have been m ade by a num ber of districts.
T he various papers presented at these sections are covered in pages 348 to 354 of this issue o f Coal Age.
Technical discussions closed F riday m orning with a session devoted to problems of cutting, shearing, snub
bing and blasting. C utting and shear
ing were handled in a paper prepared by I i . C. M cCullough, Consolidation Coal Co. T. W . Gray and J. T. Clark, P ittsbu rg h Coal-Co., offered a paper on recent developments in drilling equipm ent and practice. T he use of the CO s cartridge was the subject of a paper by P aul W eir, Bell & Zoller Coal & M ining Co. S terling S.
Lanier, Jr., N o rto n Coal M ining Co., discussed the use of explo
sives in a self-tam ping recoverable cartridge.
D r. L. E. Young, vice-president, P ittsb u rg h Coal Co., was chairm an of the general program committee.
M rs. Young headed the ladies’ aux
iliary.
T he meeting of the board of gov
ernors of the m an ufacturers’ division of the Congress resulted in the elec
tion of H . A. Buzby, K eystone L u bricating Co., as chairm an of the division, vice H . K. P o rter, H y a tt R oller B earing Co., who becomes an honorary chairm an. Charles W haley, M yers-W haley Co., was elected third vice-chairman. C. L. H erbster, Hockensm ith W heel & M ine C ar Co.,
L . W akefield Shugg
succeeded M r. Buzby as first vice- chairm an, and F. J. Maple, John A. R oebling’s Sons Co., advanced from third to second vice-chairman.
P. H . Grunnage, Westinghouse Electric & M fg. C o .; E. R. Heitzman, Central F ro g & Switch Co.; J. T.
R yan, M ine S afety Appliances Co., and R. H . Jeffrey, Jeffrey M fg. Co., were added to the governing board of the division.
L. W . Shugg, General Electric Co., again served as director of exhibits.
A nalysis o f M echanisation Progress and Tendencies by States
S ta t e A la b a m a .
P r o g r e s s P r o g r e s s s lo w in fa c e o f diffi
c u lt c o n d itio n s
A r k a n s a s .
C o lo ra d o .
Illin o is a n d I n d ia n a K e n t u c k y . . . .
M a r y la n d . . . .
M o n t a n a ...
M in in g M e th o d s C h a n g e s in m e th o d s te n d in g
to w a r d lo n g fa c e a d v a n c in g ( le n g th o f fa c e s b e in g i n cre a se d
L o n g w a ll f a v o r e d a n d d e v e lo p e d b e y o n d e x p e ri
m e n ta l s ta g e
P r o g r e s s f a i r ... C h a n g e s r e s tr i c te d b y rig id e n f o r c e m e n t of m in in g la w s
P r e d o m i n a ti n g M achine T y p e s C o n v e y o r s
R a p id p r o g r e s s in P a r is b a s in C o n v e y o r s
3 v o rs ; m in e s
C o n v e y o r s ; few loading m a ch "
P r o g r e s s s a t i s f a c t o r y . . L i t t l e p r o g r e s s ...
N e w M e x ic o ..
O h io ...
O k la h o m a ___
P e n n s y lv a n ia W e s t e r n . . . .
L i ttl e p ro g r e s s ; lo w r e c o v e ry o f e a r lie r m in in g r e t a r d s p ro g re s s a t p r e s e n t L i ttle p r o g re s s ; j u s t s t a r t i n g . . O n ly b e g in n in g ...
A t a s t a n d s t i l l ...
S lig h t p r o g r e s s ...
R o o m a n d p il la r ...
O ld la y o u ts b e in g c h a n g e d m o r e o r le ss ; s o m e ro o m - a n d - p i lla r m in in g S o m e lo n g fa c e e x p e r i m e n t s ..
N o n o ta b le d e p a r t u r e fro m o ld m e th o d s
S e v e r a l lo n g fa c e e x p e rim e n ts L o n g fa c e e x p e r im e n ts ..
M u c h e f f o r t; p r o g r e s s slo w ; a t t e m p t i n g to m a s t e r d r a w - s la te
C e n t r a l . . . . M a k in g r a p i d p ro g re s s .
A n th r a c ite U t a h ...
V ir g in ia ...
W e s t V irg in ia N o r t h e r n . .
S o u t h e r n . . .
W y o m in g ..
N o tic e a b le p r o g r e s s ...
G o o d p r o g r e s s ; u n d e r g r o u n d c o n d itio n s c h a n g e a b r u p t ly ; e a c h m in e a n in d iv id u a l p ro b le m
M e r e ly s t a r t i n g ...
D is c o u ra g in g ; li t t l e e ffo rt to w a r d m e c h a n iz in g ; c o n d itio n s d iffic u lt
P r o g r e s s in g ; o n e c o m p a n y w ith p r o p e r t y e x te n d in g in t o V irg in ia is c o u n t r y ’s la r g e s t p r o d u c e r o f m e c h a n ic a lly lo a d e d co a l P r o g r e s s h ig h ly s a tis f a c to r y
R a d i c a l d e p a r t u r e s f r o m r o o m - a n d -p illa r m e th o d s h a v e failed
R o o m a n d p illa r a n d m o d ifi
c a tio n s th e r e o f fo r c o n v e y o r V s y s te m fo r s c ra p e rs S lig h t m o d if ic a tio n s ...
R o o m a n d p il la r ...
R o o m a n d p illa r..
R o o m a n d p il la r ; s o m e lo n g fa c e m o d ific a tio n s
L o a d in g m a c h in e s M ix e d e q u ip m e n t ty p e s
A few c o n v e y o rs
A fe w lo a d in g m a ch in es C o n v e y o r s a n d sc ra p e rs
S e v e ra l c o n v e y o r u n its C h ie fly lo a d in g machines;
s o m e c o n v e y o rs
C o n v e y o rs , s c ra p e rs and r o c k - n a n d lin g lo a d e rs S h a k in g c o n v e y o rs M o s tly lo a d in g m achines; a
fe w c o n v e y o rs a n d sorapers
L o a d in g m a c h in e s a n d sev
e r a l s h a k in g co n v ey o rs
L o a d in g m a c h in e s , conveyors
R o o m a n d p illa r w ith m o d i- S h a k in fic a tio n s
ta k in g c o n v e y o rs wlt d u c k b ills , a lso scrapers a n d lo a d in g m a ch in es
.340 C O A L A G E — Vol.3 3 ,No.6
p RACTICAL OPERATING MEN
Hold Fifth Annual
Experience Meeting
W I T H M E C H A N I Z A T I O N as the m a g net, hundreds o f practical coal op eratin g men again w e re drawn to Cincinnati, Ohio, last m onth to attend the fifth annual con
vention o f %operating men held under the auspices of the American M in in g C on gress and the exp osi
tion of coal mine equipment stage d by the m anu
facturers’ division o f the sam e o r g a n iza tio n at the Cincinnati M u sic H a l l, M a y 7 -1 1 .
Since the com plete success o f m e ch an ized m in
ing depends.not only upon equipment but upon the co-ordination o f every p hase o f o p eration by a sympathetic and alert m a n a g em en t the p ro g ra m made provision fo r the discussion o f these com ple
mentary themes. B egin n in g w ith a discussion o f management and s a fe ty problems, lead in g on
th rou gh p ow er and underground h au lage to a review o f d evelop m en ts in w et and dry cleaning, the convention then swung into a consideration o f m ech anization proper and ended w ith a session d ev o te d to recent p rogress in cutting, shearing, snubbing and blasting.
Possibly the m ost significant d e v elo p m en t in the discussions w as the gen eral acceptance o f the principle o f m ech anized mining. W h e r e , a fe w years ago, the question u pp erm ost in the minds o f m ost practical op eratin g men w a s “ can it be d o n e ” interest at the Cincinnati convention centered around w h a t producers had achieved in m ech a
n ized op eration s and h o w th eir experience could be given application in solv in g the prob lem s o f th ose mines which h ave not y et fallen into line.
Quality of Man Power a Tangible Asset
ACCORDING.to H . A. Treadwell, TV engineer, Chicago, W ilm ington &
Franklin Coal Co., who spoke at the opening session relating to m anage
ment and safety problems, mines now often have so m any men in them as to necessitate a new type of m anage
ment. This m ust -be based on ac
curate reports, made by subordinates, showing the status in every p art of the mine at all times.
In a large mine the organization should be as designated in the chart shown on the following page.
Each face boss is mine m anager for his section. Because he has under him only 75 to 100 men, he is able to give intensive supervision to all operations.
The motor boss is really the chief dectrician of the mine. H e has direct charge of the repair w ork on m otors, of the advance of feeder cable and {he bonding of track. ' H e it is who should limit the num ber of cars on a triP» which m otorm en too often try to make the largest possible, regard
less of damage to equipm ent or tmlure to accomplish results.
L . Robison
T he haulage boss should direct transportation through a good tele
phone system and a dispatcher sheet showing time of arrival, num ber of
loads, from w hat parting, tim e of d eparture from bottom, num ber of' empties and the p arting to which they are destined.
T o H . S. Gilbertson, director of personnel, Lehigh Coal & N avigation Co., L an sfo rd , Pa., the quality of the m an pow er is ju st as tangible an asset to the plant as the freight rate d if
ferential or th at of coal quality. Men who are intelligent, who do their u t
most, who w ork as a team, are as likely as a low freight rate or a high standard coal to m ake a mine a suc
cess. T o get th at result labor prob
lems m ust be considered in term s of the future. T h e conditions of to m orrow are the outcome of the present.
M en should be chosen fo r jobs, said M r. Gilbertson, who are physi
cally and m entally fit, but they must in addition be individually trained.
E ffort m ust be m ade to provide som ething m ore than w hat he picturesquely term ed “the folklore m ethod of training.” T h ere is a right way of doing everything, which the w orkm an has not always discov-
h'ne, 1928 — C O A L A G E 341
F ifth A nnual Practical Operators’ Experience M eeting
ered or learned from his fellow laborers.
A third means of increasing p ro duction by improved man power is thorough training in organization, which is needed because the attitude of the managem ent itself often is wrong. E very man has a leader, the m an to whom he looks for guidance, the man on whom he leans fo r help.
W ho is it?
T he forem an is near him every day. If he cannot lead the workm an, the forem an m ust be lacking in the qualities of leadership. Care should be taken that the forem en know how and in w hat direction to lead.
In the absence of Charles Enzian, mining engineer, B erw ind-W hite Coal M ining Co., W indber, Pa., R. G.
P fahler, his assistant, read his paper.
T o M r. Enzian it seemed that rock- dusting had been delayed m ore by a lack of conviction of its efficacy on the part of the operator than by any desire to curtail expense at the risk of life.
M r. Enzian gave the status of rock-dusting in the various E astern states. In Pennsylvania about 33 per cent of the mines w ere thus protected and in M aryland about 5 per cent.
H e said that in the latter state many of the mines were quite wet and free of gas, rendering the use of rock dust less general than in some other states where the coal was dry and gas was prevalent.
J. E. Jones, safety engineer, Old Ben Coal Corporation, W est F ra n k fort, 111., declared that 97 per cent of the production in F ranklin County, Illinois, came from rock - dusted mines. T he count}' had a capacity of 105,000 tons of coal daily in 1927 and 102,500 tons of that capacity was from mines rock-dusted. In southern Illinois as a whole 30 per cent of the mines needing rock-dusting w ere so' treated. The strip-pit mines did not, of course, need rock-dusting ■ and those having longwall and other w ork
ings under a soft shale roof are safe
without such protection, for the con
tinual crum bling of the roof provides the needed inert dust.
M r. Jones said that the haulage roads of the Old Ben Coal C orpora
tion were given so complete a rock- dusting as to render the road dust wholly inert. D ust was shot into rooms from the room n e c k s,. but no fu rth e r provision was m ade for their rock-dusting. A ircourses if tracked were rock-dusted, and if trackless were guarded by troughs.
Daniel H arring to n, chief engineer, safety division, U . S. B ureau of Mines, W ashington, D. C., declared in his paper th at of 54 ignitions, fires and explosions th at occurred in 1927 and caused 229 deaths, 21 w ere due to electricity. T here also were 13 ignitions, fires and explosions w ith 31 deaths from the use of open lights and 13 disasters from blasting with dynam ite or black blasting powder w ith 37 deaths attendant thereon.
In 1927 non-permissible electrical equipment caused, by ignitious, fires Diagram o f Underground Officials, C. W . & F .d o a l Co.
M IN E MANAGER.
M a c h i n e B o s s
R epair Machine
m e n Men
A s s i s t a n t M i n e M a n a g e r
A s s i s t a n t M in e M a n a g e r
i •i
S ix o r Eight Fa ce B o s s e s
S ix o r Eight Face B o s s e s
M o t o r a n d
W ire B o s s S a f e t y
B o s s
H a o la g e B o s s o r D isp a t c h e r
I
A s s i s t a n t H a u l a g e B o s s (Travels Roads)
and explosions, at least 151 deaths;
in 1926, 123 deaths. Between Jan. 1, 1921, and Jan. 1, 1928, ignitions, fires and explosions from non-permissible equipm ent caused 700 out of 1,820 such disaster fatalities.
M r. H arrin g to n declared a device was needed that would test both for explosive gas and oxygen content.
T he industry also needed an efficient and not too expensive permissible storage battery to displace electric w iring in mines, an effective and not too costly fireproofing material for mine tim ber, a device for detecting unsafe or unstable roof, a more de
pendable roof support than timber, a safe substitute fo r all kinds of ex
plosives, a device or method for handling hangfires or misfires, a safe and efficient flood light, a wholly en
closed mine car and a car wheel that would not break, a reasonably inex
pensive belt haulage to eliminate mine cars and locomotives, a trailing cable that would not arc on being attached or detached from power lines and would not become short-circuited by falls or when wheels passed over it.
H e also suggested the need for a device on cutting machines for the complete removal of bug dust from the kerf, a method, for propelling m ining machines from place to place without “ nipping,” a device'to warn men autom atically whenever the m ethane content exceeds 2 per cent, a method of stopping man trips on grades ranging from 35 to 70 per cent in case of breakages of couplings, pins or ropes, an inexpensive, fire
proof, efficient door.
In discussing. M r. H a r r in g t o n ’s
paper Jo hn T. R yan, Mine S afety
Appliances Co., P ittsburgh, Pa., said
that 12 to 17 per cent of the fatalities
were due to explosions and that 99 per cent of the unfavorable publicity
the industry received because o f its accident record was based on this small percentage of its accidents. It should make every effort by rock-
dusting and ventilation to rid itself
of this cause of accident.
W . H . Glasgow, Secretary of M ines, S tate of Pennsylvania, Harris
burg, Pa., presented a paper by R ichard D. Maize, state inspector.
Uniontow n, Pa., on the ventilation of gaseous mines. M r. Maize stressed
the im portance of having two driving units fo r each fan, either one of which could speedily be connected m case of the failure of the other, to-
342 C O A L A G E - ■ V o l.3 3 ,^ -6
F ifth A nnual Practical Operators’ Experience M eeting
gether with an auxiliary gasoline drive incase the other two failed.
He advocated that the intake a ir
way capacity be m ade greater than that of the return w herever the in
take air is conducted through the haulageway, which is the proper a r
rangement. The intake, he said, is
always m ore or less obstructed by trips and needs to be the bigger despite the textbooks th a t lay too much stress on the volume of the gases added to the mine air. H e thought the velocity of the air should be kept down to 850 ft. per minute, especially at the face, to prevent the
transpo rt of coal dust by the air current.
C. P. B yrne said that there should be pressure over pillar falls so as to drive the gas either to heading
“bleeders” or to drillholes. W . L.
Robison, Youghiogheny & Ohio Coal Co., Cleveland, Ohio, presided.
Servicing the Men at the Face H
AULAGE systems and powerwere topics at the T uesday m orn
ing session, at which A. C. Callen, professor of mining, U niversity of Illinois, presided.
C. E. W atts, mechanical engineer, Benvind-White Coal M ining Co., read a paper describing the present trend, and advocating certain changes, in mine-car design. H e recommended that the mining company keep a set of plans and specifications extending to minute details, in order th at bidders be placed on an equal basis and the user have an opportunity to record and follow up im provem ents th at may be suggested by service.
The use of copper-content steel which has an appreciable resistance to corrosion, was advocated. U se of thinner sheets of this m aterial crimped for extra strength, malleable castings, alloy or heat-treated axles, smaller wheels, neater brake rigging, and tight ends in place of gate ends, was sug
gested as a way of increasing the present 60- to 66-per cent ratio of live load to total weight.
TUBRICATION costs over yearly
■‘-'periods in Berw ind mines were
?2.39 and $2.05 per car per year for two groups of plain-bearing cars, and 33c. per car per year fo r a group equipped with tapered roller bear- mgs. The data pertain to about 14,000 cars.
Mr. W atts explained that 600 of the Berwind cars, six years old, are
°f open-hearth steel and the balance copper-content steel. T he form er deteriorate by shedding large scales 0I" rust but the copper-content cars show only slight pitting. Recently 1-050 more cars w ith copper content Were ordered. T he percentage of c«PPer is 0.15 to 0.25.
. D. Hockensmith, Hockensm ith ''heel & M ine C ar Co., called at
tention to the improved plain bear- lngs that are available today, and said hmc, 1928 — C O A L A G E
A . C. Callen
►
that the pushing of cars, one arg u m ent for the use of anti-friction bearings, is fast passing out of date.
In reply M r. W a tts stated th at his company ran 18,000 tapered roller bearings 18 m onths on one lubrica
tion. H e believes that a mine car equipped w ith anti-friction bearings will ru n 4,000 miles per lubrication.
C
O M M O N practice in locomotive haulage fo r large m ines was given a jolt in a paper by R. L.Adam s, chief engineer, Old Ben Coal Corporation, W est F ra n k fo rt, 111.
John L and, assistant to the u n d er
ground m anager of the company, read the paper, and at points elaborated on the text.
Old Ben No. 8 mine, opened in 1910 and brought to a production of over 5,000 tons per day by 1920, uses no m ain-haulage locomotives, but in
stead the gathering locomotives haul
the trips of 7 to 14 cars directly from the room entries to the sh aft bottom.
Grades vary from 0 to 5 and 7 per cent, and the cars carry an average of 2.5 tons.
As the production was increased additional gathering locomotives were added, and passing tracks near the shaft bottom extended until now the m ain roads are double-tracked fo r a half mile from the sh aft bottom in each direction. O f the twelve mines operated by the Old Ben company, the three which were opened by that firm contain no m ain-haulage loco
motives. Costs over a two-year period show th at the haulage in these three run s approxim ately 2c. under that in the other m ines of equal pro duction but equipped w ith main- haulage locomotives.
A dvantages claimed are : few er mine cars needed because none stand idle on partings, locomotive waits at"
partings eliminated, wrecks less severe and m ore locomotive help available fo r clearing a wreck, and better supervision of haulage men because they periodically come to *he main bottom.
“ H p H A T ’S w hat you call railroad- X ing,” was the comment of an operator a fte r hearing a paper by R. M. Flem ing, engineer, Ebens- burg Coal Co., describing the un der
ground transportation system at the com pany’s No. 1 mine in Cambria County, Pennsylvania.
Tw o 224-ton and four 15-ton loco
motives, assisted on sections of 4-per cent grade by 15-ton pusher locomo
tives, handle the m ain haulage.
R ound-trip distances are from 2 to 7 miles, th e num ber of cars handled is 48 to 64, and the mine production is 4,000 tons p er day.
T h e.co a l is 34 ft. thick and the track gage 36 in. T h e car equip
m ent consists of 1,710 wood-bottom copper-content steel cars weighing
F ifth A nnual Practical Operators Experience M eeting
The m agnitude of anthracite pum p
ing operations was indicated by a statem ent that the annual power cost of pum ping is about $5,000,000.
A utom atic substations were treated in a paper by W . C. Shunk, general m anager, Stonega Coke & Coal Co., Big Stone Gap, Va.
A
S U R V E Y as of A pril 1, 1928, revealed that there are 819 auto matic equipm ents in the m ining industry and these total approxim ately 235,000 kw. D uring the last calendar year 93 autom atic equipments, or roughly 33 per cent of' the total num ber sold, w ent to coal mines.
T he advantage of autom atic sub
stations from the standpoint of sav
ing in feeder copper was indicated
R obert M . Lainbic
said that the first installation in a mine of the Lehigh company was made in 1924, and that to date 33 units have been installed.
- u
2,700 lb. each, m ounted on Tim ken roller bearings and having a capacity of l-J tons.
M an power, except where local conditions demand a hoist, is used between the room face and the room heading. Locomotives of 10-, 12- and 15-ton capacities assemble the cars on the side tracks ready for the main haul. T he average daily output per loader is 9 \ tons.
T he W estinghouse 224-ton loco
motives are equipped with 90-hp.
m otors and semi-magnetic control.
The center axle has flangeless tires fo r perm itting easy travel on curves.
T he wheels are 36 in. in diameter.
M r. Flem m ing gave the minimum radius for the 224-ton locomotives as 150 ft., and said th at the dispatcher times the trip starts so fa r as pos
sible to avert unnecessary load peaks.
A
F U R T H E R advantage that can .b e credited to automatic pumping is the feasibility of installing pumps at the various levels, thus saving the lifting of much of the w ater from the lowest level where a m anual pum p station of large capacity would be located. A s to the “squirrel cage or slip rin g ” question, Mr. Wag
ner said his company is using success
fully' a 550-hp. squirrel-cage pump m otor, and th at he keeps the starting disturbance to a m inimum by' careful adjustm ent of the relays. One re
quirem ent is to time the closing of the line contactor to occur before the w ater in the discharge line attains velocity'.
Tim e clocks are used in connection with float controls to help keep the pum ps off the power peaks.
T N C L O S IN G his remarks Ur.
A W agner emphasized that automatic control does not provide automatic maintenance, and th at auxiliary con
tacts should be so constructed as to w ork w ith certainty without frequent or daily polishing. “O u r experience with autom atic pum ping stations has been very' satisfactory; in fact we have had less trouble than with the m anual.”
F . L. Stone, of Schenectady, said that cleanliness and satisfactory op
eration go hand in hand. “Show me an autom atic pum ping station that is not kept clean and it will be one that gives trouble.”
R. J. W e n s l e y , o f W estinghouse, s a i d t h a t c o n s i d e r i n g t h e sm all extra
I
N T H E absence of J. T. Jennings, Philadelphia & R eading Coal &Iro n Co., his paper was read by Dr.
H en ry Mace Payne, consulting engi
neer of the Am erican M ining Con
gress.
The paper described a 7,000-gallon- per-m inute autom atic pum ping sta
tion made up of three 500-hp. six- stage centrifugal pum ps operating against a 600-ft. head. Details of the control sequence were given.
A supervisory system, not a com
mon accessory to pum ping plants, is an interesting feature of the plant.
It consists of a panel in an outside substation on which lamps of various colors, a m eter and a gong indicate the im portant station conditions and the duration of the starting cycles.
O ver 150 autom atic pum ping plants are in use in the anthracite mines of Pennsylvania and these are saving $500,000 per year in labor.
M rs. L . E . Y oun g Chairman, Ladies’ A u x ilia ry by' citing the case of a company which in 1915 replaced five power plants, serving six mines, by substations near load centers, and thereby recovered sufficient copper to meet the entire demand of eight m ines fo r eleven years. These eight mines produce about 3,000,000 tons per year.
T h e discussions of autom atic pum p
ing and autom atic substations w ere combined. M r. W agn er gave credit to M r. Jennings for being the first to put over the idea of full-autom atic control of mine pum p stations. H e
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