68

THE COLLIERY GUARDIAN.

January 11, 1918.

much more than do the negative. It is usual, there-
fore, in a two-pole machine to find distinct trails of
the positive brushes, whether they are staggered rela-
tively to the negative or not. With multipolar
machines, however, the case is different, and it is
possible to get fairly even wear all over the surface of
the commutator.

The staggering should be done in pairs of brush arms,
and not alternate; that is, if we start with a positive
arm, the next arm which is negative should trail the
positive, but the following positive brushes should be
run about half the width of a brush to one side of those
on the first positive brush arm, so that it is possible
to cover the whole width of the commutator with posi-
tive brushes situated at different points around the
commutator.

Lubrication.

Few commutators will work satisfactorily without
some sort of lubrication. In some of the very soft
grades of brushes the graphit’e forms sufficient lubrica-
tion in itself, but the harder varieties of brushes work
much smoother when given a little lubricant.

One of the most beneficial means of supplying this
lubrication is to use just a little paraffin on a clean rag
and apply it to the commutator when the latter is warm
and not when it is cold. The rag should be practically
dry, as any excessive use of the paraffin will cause
dust and other foreign matter to adhere to the brushes
and commutator.

Turning or Grinding Commutators.

When a commutator is allowed to get into bad con-
dition, the only remedy is to have it trued up. This
may be accomplished by turning in a lathe or in posi-
tion, the latter being preferable; but where a suitable
grinding machine is available, it should be used. In
any case, it is more satisfactory to true the commutator
in position, as there is then no uncertainty about its
being true when running.

For turning, the tools should be sharp and the cut
taken very light, as otherwise the copper will be
dragged over into the mica between the bars. This is
specially the case when the mica is below the surface
of the commutator and no support is given to the edges
of the bars.

Iz >

L____________j

Fig. 4.

The edge of the commutator should be slightly
rounded, as shown in fig. 4, in order to prevent the
otherwise sharp corner from being damaged by a slight
knock, and the segments thereby short-circuited. This
also applies to the other end of the commutator next
the armature connections. This edge should not be
left sharp, but carefully rounded off on to the commu-
tator. The radius of the curve for both ends should
be about | in. for small machines, whilst in the larger
sizes the end next the armature may be given a wider
sweep.

Bedding Brushes.

This naturally follows the turning of a commutator,
as the old surface of the brushes will not conform to
that of the newly-turned commutator. The operation
requires care and patience to be carried out properly,
the usual method being to place a piece of emery cloth
around the commutator with the rough side against
the brushes. The emery is then worked backwards and
forwards while the ends are kept flat on the commutator,
no slack being allowed to work up in waves against the
brushes, as this wears off the edges of the brushes and
reduces the contact surface.

In conclusion, it may be said that prompt attention
to commutator ailments is, essential to satisfactory
operation.

New South Wales Coal Mines—A cablegram states that
the New South Wales Government has undertaken to supply
the States of Victoria, South Australia, and Western
Australia with all the coal they need during the next five
years. There appears to be a strong belief that the New
South Wales Government intends to nationalise all the coal
mines in the State.

Coal Mining in Venezuela.—The Gaceta Oficial (Caracas)
publishes the text of a contract entered into between the
Venezuelan “ Ministerio de Fomento ” and Elias Rodriguez
Gonzalez for the working of two coal mines situated in the
El Pilar Municipality, State of Sucre, the Government
leasing the deposits for a period of 30 years. The conces-
sionaire must commence the working of the mines within
three years from the date of the approval of the contract.
For the lease of the mines, the concessionaire will be
required to pay 2 bolivars (Is. 7d.) in respect of every
metric ton of coal produced.

Donetz Coal Basin.—According to calculations made, cer-
tain unfavourable views entertained of the Russian coal
reserves are without foundation, and the corollary that
Russian industry will not be supplied with the necessary
heat is equally unfounded. There can be no doubt that in
the progress in technique that will be brought about quite
likely in the near future in the form of sources of energy,
various natural powers will be largely taken advantage of.
Therefore, industry should not be based entirely on the pros-
pects of obtaining enough* coal. In any case, the ques-
tion before us is that the great development of industry is
a necessity to Russia. Therefore, all possibilities of develop-
ing industrial Russia should be used as skilfully as possible.
In the first place, as to the Donetz coal basin, we must
remember that, of all the reserves in that basin, about a
third is coking coal, and the remaining two-thirds are of
anthracite. The problem of the proper use of the coal pro-
duced is first to adapt all the furnaces and the locomotives
and boilers to the consumption of anthracite; then a con-
siderable portion of coking coal would be released for the
use of the metallurgical industry.

ORGANISING SAFETY WORK IN
MINES.*

By H. M. Wilson and J. R. Fleming.

During the past few years there has been marked
progress in safety work by mining companies. Such
work has usually been started and directed by an
executive, with the aid and advice of individuals or
committees reporting to him, independently of the
operating department. The practice has been to awaken
the interest of the employees in the causes, results, and
avoidance of accidents; to convince them of the
genuine desire of the company to bring about increased
safety; and to obtain the co-operation of officials and
employees in suggesting and adopting protective
measures.

At first there was some doubt regarding the perma-
nency of a movement that had its inspiration in human
welfare and for its prime purpose the safeguarding of
life and limb. The experimental stage has passed,
however, and from the united work of many hands and
minds practical results are being obtained. Many
mining companies have been quick to adopt the more
desirable safety measures, such as the creating of safety
departments and the requiring of more careful super-
vision at the mines. Mining laws have been greatly
improved and more strictly enforced. Various local
and national organisations have been formed for pro-
moting safety and standardising methods. The
enactment by several States of workmen’s compensation
legislation, with the consequent insurance against
casualties, has aided the safety movement. Much
progress has been made in educational work through
various agencies. Altogether the movement is com-
manding much attention and must result in saving
many lives.

As has often been the outcome in movements for
human welfare, additional advantages other than those
anticipated at first have resulted. Accident prevention
has not only meant fewer injuries and consequently
less suffering and distress to miners and their families,
but has increased the efficiency of plant operation, so
that economic gain has followed. The present tendency
is toward standardisation and greater uniformity in the
measures vitally affecting the safety and health of all
employees. It is to be hoped that this tendency will
fully crystallise, so that the valuable data furnished by
experience, scientific investigation and experiment will
serve as a useful basis in solving problems that con-
front the mining industry.

The purpose of this report is to call attention to some ,
of the means adopted for promoting greater safety in
and around mines, in the hope that their presentation
will stimulate activity and aid those endeavouring to
solve safety problems in the different mining fields. It
deals primarily with the organisation of safety work,
which is a fundamental requirement for an effective
campaign in accident prevention. Concerted action by
officials and workmen is essential if this economic and
humane movement is to have the success it merits.

The Bureau of Mines has received many enquiries
regarding safety organisation and the means of
creating and sustaining interest in mine safety. To
meet this demand the mining engineers of the bureau
and the authors of this report have devoted much time
to collecting data concerning the methods adopted by
those companies that maintain safety organisations.

An endeavour has been made to arrange these data in,
such a way as to present a system for practical applica-
tion in either large or small mines, be they coal or
metal. The existing organisation of every mining’
concern is adapted to the creation of a safety organisa-
tion. New employees will be necessary only for very
large operations. It is not expected that a company
employing a comparatively small number of men would
adopt measures on the same scale as a company having
many large operations, but the same general principles
apply, and any variations need be those of degree only.
The expense for safety work will, of course, vary; but
experience indicates that whatever the investment, it
will pay a good dividend.

No special reference is made to the many mining
companies, both coal and metal, that have efficient
safety organisations' in operation, but the recommenda-
tions presented are based on a study of these.

Organisation of Safety Work.

In organising safety work cordial co-operation and
enthusiasm are essential. The definite purpose of a
safety campaign is the immediate reduction of easily
preventable accidents and a gradual reduction of all
accidents. The number of accidents occurring annually
is convincing proof that the problem demands a
vigorous and continuous campaign backed by adequate
financial support, and above all by the active sympathy
and energy of some of the highest officials in each
mining company. Experience has proved that satis-
factory conduct of a safety campaign requires organi-
sation for carrying out three branches of work, as
follow:

1.	An organisation that provides an enthusiastic and
hard-working safety committee or department, an
adequate inspection system, and hearty co-operation of
officials and employees.

2.	A system of education that will assist all
employees to follow more carefully the safe and proper
methods of work and will keep them constantly alert to
the need of caution.

3.	A scheme of safety measures designed to eliminate
as far as possible dangerous conditions that have
caused accidents or may cause them.

The approximate relative values of these different
factors have been estimated by R. J. Young, head of
the safety department of the Illinois Steel Co., as
follow: Organisation, 45 per cent; education, 30 per
cent; safety measures, 25 per cent.

In giving relative values to these factors the majority
of the leading advocates of safety in the various
industries place the greatest emphasis on organisation
and education. The lowest value is placed on safety

* From United States Bureau of Mines, Technical Paper
103.

measures because of their inadequacy in themselves,
so far as preventing most accidents is concerned. The
figures, although a mere approximation at best, form a
practical basis for promoting safety work.

Preventable mine accidents are generally attributed
to carelessness, insufficient inspection, inexperience,
unsafe practices, lack of safeguards, violation of
instructions, indifference, defective equipment, use of
intoxicants, insufficient lighting, poor judgment, and
other indirect causes. The “ safety-first ” movement
, aims at minimising such preventable accidents.
“Safety first” means simply that safety must be the
first consideration during any and all parts of the day’s
work, that every precaution be taken to prevent
accidents by making conditions as safe as possible, and
that the best and safest methods practicable be always
employed so as to avoid unnecessary exposure to risk.
The purposes of “ safety first ” are thoroughly practical.
In some of the leading industries safety campaigns
have resulted in reducing by 30 per cent., and even 70
per cent., the number of accidents that had been
occurring annually for a period of years.

The initiative in safety work must be taken by the
management. Usually in starting an active safety
campaign the officials hold a public mass meeting, at
which data showing the possibilities of the work are
presented to the employees.

Safety Department.

An organisation imbued with the value and impor-
tance of preventing accidents must get its inspiration
from the president or owner. This must be passed
down with undiminished vigour through the general
manager, superintendent, foreman, and subordinates.
The never-flagging interest of these officials in the
safety of their workmen must be expressed and reiter-
ated through the medium of rigid inspection, the
installation of safety appliances, safety committees, the
posting of notices and warnings, promotion of first aid
and rescue training, provision for care of injured, and
such educational means as lectures, rallies, and miners’
field meets.

Organisation of safety work naturally differs some-
what in the various mining fields, largely in con-
sequence of local conditions, whether the mines are coal
or metal, and the number of men employed. With
certain changes to suit large or small operations the
following scheme has proved successful and should
serve as a basis for new organisations:

Safety Inspector.

A large company operating several mines should
have a safety department, in charge of a safety
inspector or a safety engineer, depending upon the
number of mines and the extent of the operations.
His services should be devoted solely to safety work,
independent of the operating department, and he should
report directly to the executive. A person charged
with and responsible to the executive for the adoption
and enforcement of safety measures is far more effec-
tive in producing results than any committee.

The department chief may have one or more assistant
inspectors for carrying on the work according to the
extent of the territory and the number of operations
under his supervision. Regular and careful inspections
of all equipment and of conditions in every mine are
made and proper safety measures are introduced. The
inspector should receive the co-operation and active
support of superintendents and foremen in furthering
such work.

In smaller operations the safety work must neces-
sarily be more closely associated with the operating
department, in which event the inspector may perform
duties other than those connected with mine inspection.

The mine rescue and first-aid department usually
comes under the supervision of the inspector. In some
instances the inspector is called upon to assist in the
welfare and educational work and to encourage, with
the view of improving health conditions, better
standards of living among the employees.

Safety Committees.

Some or all of the following committees should be
maintained according to the size and number of the
various operations controlled.by each company:

1.	A central safety committee, composed of the
general manager, general superintendent, chief
engineer, inspector, secretary, or other officials, which
should hold monthly meetings. Reports and recom-
mendations of the inspector- and of sub-committees
should be received and if practical put into effect, the
causes of accidents studied .and classified, and steps
taken to avoid the recurrence of similar accidents.
Regular trips of inspection should be made and greater
impetus given the movement by frequent public
meetings in the interest of safety. Due publicity will
thereby be given in addition to the constant evidence
afforded by the work as it progresses.

2.	A plant safety committee composed of the
superintendent, assistant superintendent, mine foremen,
captains, firebosses, electrical engineer, mechanical
engineer, mining engineer, and chief clerk. In the
smaller operations this committee might be substituted
for the central safety committee and perform the
functions outlined above; in this event the inspector
would be a member ex officio. Reports should be sub-
mitted to the executive head, usually the general
superintendent The members of this committee would
be the active agents in carrying out the provisions of
the law and such measures as may be adopted for
promoting safety. This committee should hold regular
monthly meetings for the consideration and discussion
of all safety problems and submit monthly a detailed
written report stating the progress made, with recom-
mendations. These reports would give the judgment
and recommendations of men who have had the most
intimate experience with all the various divisions of
underground work and would tend to standardise
underground practice as a whole. It is extremely
important that the foremen become actively interested,
as it is the foremen who must enforce the rules finally
adopted, and service in the committee best acquaints
them with the reasons for these rules.