Document yrOkggdMBKjOpGyoyV0jav8v6
FILE NAME Riley Stoker RS DATE 1942 Apr 16
DOC RS001
DOCUMENT DESCRIPTION Trade Journal Article - Protection Against
Industrial Dust
Vol 66
WITH WHICH IS INCORPORATED THE IRON
-
JOURLY
Thursday April 16 1942
JOURLY
Killy Esta fill
fill fill fill
puts
JOURLY ee
Stokes Stokes with fad
press
ponent
No. 1339
THE FOUNDRY TRADE JOURNAL
Council of Ironfoundry Associations
of standardisation ol design
Ripley methods of moulding composition
and
01
of metal
4. Wellington Street Londan W.C.1
Chairman Fitzherbert Wright The Butterley Company near Derby
fuel
economy
and
technical help in
WARTIME ADDRESS to which all communications should be sent
Westminster F
until further notice
Secretary V. Delport 2. Caxton Street
5.W.I.
achieving the production of high grade
- 3 Amersham Road HIGH WYCOMBE Bucks
fighting Telegraphic Address ;
"
Zacatecas
High Wycombe
Telephone HIGH WYCOMBE 1792 43 lines
@ PUBLISHED WEEKLY Subscription Terms Home and Oversees Zie
All Subscriptions are payable in advance
per annum
Participating Associations National Ironfounding Employers Federation
Bratish tronfounders Association
Association
National
of
Malleable Ironfounders
Ironfounders Ironfounders
Ironfounders National Confederation
British Bath Manufacturers Association British Malleable Tube Fittings Association
Cast Iron Chair Association
castings It would advise the Director of Steel Castings and operate with the services in the simplification of design We
leave the obvious utility of such an organisation for post development to the imagination of the leaders of the steel foundry industry The American counterpart of the General Stee
OFFICIAL ORGAN OF
The Council of Ironfoundry Associationi
The institute of British Foundrymen
Enamellers
Enamellers
The Instiute of Vitreous
The Welsh Engineers and Founders Association
The Foundry Trades Equipment and Supplies Association
Greensand Pips Founders Astociation of Scoriand
Cast Iron Heating Boiler and Radiator Manufacturers
Association
Cast Iron Segment Association National Ingot Mould Association Cast Iron Axlebox Association Institute of British Foundrymen affiliated British Cast Iron Research Association affiliated British Grit Association affiliated
Castings Association has provided all the neces
sary pointers It is obvious that by the creation of such an organisation as we have outlined that the industry will gain in status for it mus
be borne in mind that employers association
except those negotiating with the trade unions exist for three purposes only One is to ensure an economic return for their efforts the second
Institute of British Foundrymen
PRESIDENT : 1941-42
Major R. MiesM.Eng Head Wrightson & Company Limited Thornaby
LIST OF SECRETARIES
Ganaral Secretary T. Makemson Sait John Deansgate Manchester 3. London Office Street Deansgate
Street Chambers > 49. Wellington
Agricultural Engineers Association affillated
One More Committee
It appears to us that for the better prosecution of the war there is need for the creation of
still one more committee This superficially
to provide a voice to speak for the industr in matters concerning Governmental orders and
other influential bodies and the third which w
rate us of equal importance the giving of service
to its customers
At the moment the all-
important customer is the Government through its various departments and we have overv
reason to believe that the step we propose will
BRANCHES
Birmingham Coventry and West Midlands A A Timmins F.JC 21-23 St. Paul's Square Birmingham 3
Ear Midlands S. A. Horton " Three Mostyn Avenue Little
over Derby
Lancashire : A. Boyer ** Roseville 7 Kirkstall Road Davyhuime
Manchester
London V. C. Faulkner 3. Amersham Road High Wycombe
Middlesbrough pro tem J. K. Smithson Essgarn from
Refining Company Limited Stillington Stockton : Newcastle C. Lashly Sir W. G. Armstrong White
worth & Co. ronfounders Ltd. Close Works Gateshead
Scottish : J. Bell 60 Sc Enoch Square Glasgow Sheffield W. Webb B.Sc. 20 Brookfield Avenue
Swinton
Mexborough Yorks
Waier and Monmouth : J. J. McClelland 12. Clifton Place Newport
West Riding of Yorkshire S. W. Wise 110 Puilan Avenue
Eccleshlil Bradford
South Africa :
and Commissioner
F. C. Williams Mutual Building Corner of Harrison
Johannesburg
Streets
Johannesburg
SECTIONS
Bristol ; A. Hares 167 Ridgeway Road Fishponds Bristal
Burnley : H. Buckley Ellsmere Norfolk Avenue Burnley Lancs
Anglian East
: 1. L. Francis 12 Glenhurst Avenue Colchester Road
Ipswich
Falkirk : T. R. Goodwin " Viewfield Falkirk Road Bonnybridge
Scotland
Lincoln E. R. Walter M.Sc. The Technical College Lincoin
The Institute of Vitreous Enamellers
President : Professor 3. H. Andrew D.Sc. Department of Applied Science The University St George's Square Sheffield
Chairman W. H. Whicde W. H. Whicle Limized Eccles near
Manchester
Hon Secretary Dr. G. T. O. Marc~-n 21-23 St. Birmingham 3
Paul's Square
does not have the appearance of adding to our popularity but there is a serious gap in the Organisation of the steel foundry industry which requires filling Through lack of foresight on the part of past Governments the not inconsiderable steel foundry industry of the last war
was allowed to shrink during the slump to
dangerously small proportions Just before and
during this war there has been a very considerable expansion moreover established firms
are being required to tackle new types of jobs
and some make an immediate success of them
Whilst others require more time than can be
spared at the present for getting into production The weights of some castings vary in
order to take care of machining allowances by
more than 25 per cent This inter alia causes much coming and going between foundries in
specting each other's methods A comparison with the iron foundry organisation reveals
exactly where the steel foundry industry is weak In ironfoundry research work is carried on by
the B.C.L.R.A. which additionally and probably
preferentially is undertaking much development
work That is it makes itself familiar with new
Jobs and where difficulties in production arise
it sends its officers to the actual foundries to get
things going Then the Directors of Iron Castings have their own technical advisory committee and so has the Council of Iron Foundry
Associations
Moreover a committee of the
be enthusiastically received by the clientele we sincerely hope that our proposals will be
equally well received in steel castings circles
Book Review
New Methods for Sheet Metal Work by W
Cookson Published by The Technic
Press
Limited
.
Piccancot
Gloucester
Road Kingston Hill Surrey Price 7s 6d
The reviewer often wonders whether or no
an engineer's patternmaker could derive advan tage from a study of the methods used by sheet metal workers in setting out their jobs
The main difference of course is that metalla
sheets can be bent and wood cannot yet when
. one examines the patternmaking for a propelle
consisting as it does mainly of sweeps on sees that there can be a connection This book
appeals to the reviewer as being much more practical than the average treatise on the sub ject the illustrations which are so very im
particularly portant in this type of book are
clear Added interest is given by the fact that
entirely new methods are disclosed
Contents
One More Commutter Book Review
Foundry Trades Equipment and Supplies
Association
President G. E. Halifax
Acting Secrecary : Surrey
France August's Miss L. Cox 52.
Limited Surbiton
Thorn Tree Works
Hill Park Surbiton
Welsh Engineers and Founders
Founders
Founders Association
President W Clement C.B.E. Moria Youndry New Dock
Llanelty Secretary : . D. D. Davis 9 Royal Metal Exchange Swansea
Institute of British Foundrymen has been ener-
getically employed in creating what eventually turned out to be a group of steel foundries
The steel foundry is well served for pure research work through the joint auspices of the British Iron and Steel Federation and the Iron
and Steel Institute supported by the Genera
Steel Castings Association there is no development and advisory work in progress such as there is with iron castings and this is the very committee we suggest should be formed Moreover the committee we visualise would not
Old Metal and New
Notes from the Branches .
Random Shots .
:
wee
Foundry Production Problems with Special
Reference to High Alloy Cast Iron
War Directory of the Enamelting Industry
Tin Smelting in South Africa
24
Metallurgical Literature
Warture
oe
24
The Foundry Industry and Air Warture
241
Protection Agamat Industrial Bust
24-
Conditioned Blast
254
2
A Ministry of Fuel
Magnesium Dust Extraction
.
25
The New Patents and Designs Act
2
Cathodic Protection of Pipe Lanes
Organisation of Production
: :
De
Wholesale Price Changes in 1939-1941
28
be merely a periodic assembly of dozen BRITISH CAST IRON RESEARCH ASSOCIATION or so of the hetter known foundry managers
The Registered Office and laboratories of the B.C.J.R.A. are but the reinforcement of such a body by a high
Laboratories 11-25 ST PAUL'S SQUARE BIRMINGHAM
grade competem official supported by a staff
Telephone Colmore 4274-4275
Telegrams CIRA
The work of this permanent and perhaps some
The B.C.I.B.A. Scottish Laboratories are
what curious committec would include questions
- Foundry Technical Institute Mok's Road Falkirk Phone 332
South African Iron and Steel
Wiring of Foundries
Patent Specifications Accepted
Workers
Clothing Coupons for Industrial Workers
Fer ochureme American Ferrochureme
:
The Wook's New in Brief
Steel
Higher Prices for Speed Steel Strop ..
Raw Material Markets
Protection Against Industrial Dust
coal sugar destine cocoa various cered dusts
york shoddy and rags sulphur wood flour vittaes resins and dyes and plastics malt tea magnesium
and alummium to name but few
By KENNETH L. GOODALL M.Sc. F.Inst.P.
Oxidation of combustible material is surface
phenomenon and so is most rapid and capable of Causing explosion with material in the finely divided
Industrial dust presents two main hazards to the
Sworkers in factory and nune 1 tasks to health
risks to life and lumb through fire and explosion
from certain types of dust Many factory opera-
ions give rise to dust the chief including crushing breaking disintegrating grinding abrading drilling
sawing turning muxing seving rumbling sand-
for blasting and almost any operation in
volving material which is itself a dust or contains
2 percentage of dust The risks to health
from
industrial
dusts
arise
from the damage they can cause to the respiratory system and from the action of certain dusts as general systemie poisons or skin irritants Thus the finhalation of silica on ashestos dusts which is
cumulative in effect can cause the incurable lung
diseases of silicosis and asbestosis respectively in
which the lung tissue is gradually destroyed with the result that blood aeration diminishes the
Finhalation of animal or vegetable dusts and ot some mineral dusts such as limestone glass cement
passages catarrh
and and The
emery may affect the respiratory give rise to bronchitis asthma of
breathing of certain metallic oxide
fumes such as zinc oxide magnesium oxide manganese dioxide and copper oxide can give rise to metal fume fevers while the inhalation or swallow
zing of certain toxic dusts such as lead arsenic cadmium or manganese and their compounds
leads to poisoning Of these dangers to health the most serious are undoubtedly those due to silica and asbestos dusts and to the poisonous dusts such
as lead
Physical principles are involved at many stages in the estimation and control of dusty conditions
in the working atmosphere
Protection Against Industrial Dust
By a suitable combination of the
chemical methods which are the Paper a fair assessment of the
nature of the dust clouds being
physical and
described
amount and
breathed by
workers in any particular case can be made
Methods of protection to suit can then be devised This is the ideal approach to the problem which
can only be adopted at present in a limited number of cases on account of the time involved in such
surveys
In practice a selective survey of dusty
conditions associated with typical processes in an
industry offers valuable guidance for more general application of protective measures to generally
similar conditions in a whole industry
E In the normal individual the human nose throat
Sand lungs in themselves provide a defensive
mechanism for arresting fine dust and preventing
s reaching the ultimate air sacs in the lungs The nose traps large particles in the nostrils and finer
particles in the maze of passages above the nostrils in which dust is deposited from eddy current action
particle aggregation and from impingement on the
E
sticky secretion of mucus which lines all the air passages from the nose downwards The wind B pipe and air tubes of the lungs are also lined with E minute whip processes known as cilia whose function is constantly to sweep upwards to the windpipe for expectoration the mucus and the dust B particles it has trapped the process being aided by the rhythmic contraction of the smaller muscular air tubes Fine particles which succeed in reaching the air sacs of the lung are attacked and ingested by phagocytic cells some of which manage to carry the dust back into the air tubes where they can be expelled The importance of nose
breathing in dusty atmospheres in order that all
the natural deferces of the respiratory system may
be brought into full play will be appreciated though individuals differ widely in the power of
these defences of The main methods of protection against indus-
trial dust take a wide variety of forms
The
purpose of general ventilation is to dilute with
fresh air the dust laden air hable to be breathed
other pa of the room or the plenum system in which clean warmed and possibly humidified air is blown unto the workroom under slight positive pressure through a ducting system the air finding its way out the doors windows or other openings These methods of dealing with dust in worktoumis or a combination of them both are of strictly limsted application and are only successfully applied where the dust concentrations are generally diy seminated in the workrooms Even then the use
of general mechanical ventilation is often a confession of failure to provide what is more effective namely adequate localised exhaust ventilation
Localised Exhaust Ventilation
Localised exhaust ventilation is the commonest
and most usually effective way ol protecting
workers against local dust concentrations
The
basic idea is to capture the dust or fume as near
as possible to its point of origin by means of
concentrated air currents flowing into suntable ex-
haust hoods which need to be designed on sound
physical principles to suit each individual case The collected material is sucked away through
ducting by a fan and passes to filtration plant It is found that most industrial dusts can be captured
by exhaust hoods designed to produce a linear an
speed of from 100 ft to 500 ft per min at the
point of origin of the dust
Ducting resistance is an important item contri-
buting to running costs and proper application of
the laws governing the flow of laden air in pipes will enable resistance to be reduced to a minimum by securing a symmetrical layout of
adequate small
vided
sectioned piping fed by branch ducts at angles in the direction of air flow and prowith gradual bends tapered connections to
fans cleaning panels suitably sited smooth joints
and the like The type of fan used for dust
exhaust systems is the paddle type receiving the
dusty air approximately radially and discharging
it tangentially against resistances which may reach as high as 14 in w.g. In many cases the fans are
placed downstream from the air cleaning plant
which is thereby kept under suction an advantage
where fillers are against the best practice some
times located in workrooms The fan itself also
thereby handles practically clean air
The main types of dust collecting apparatus are
all based on physical principles and include gravi tational and centrifugal settling chambers inertial separators viscous type filters wet scrubber
filters bag filters and electrostatic precipitators Considerable use is also made of the wetting of
materials to prevent dust creation but Watson has
pointed out that in certain cases this practice may be more dangerous than dry working In some cases safe material may be substituted for dan-
gerous dusty material for example in the classic cases of the substitution of steel shot for sand in
the operation of sandblasting iron castings and of alumina for powdered flint in the process of
china bedding in the pottery industry
All dusty processes should of course be separated from other processes so as to limit the
number of workers exposed to any particular dust
risk By what is called good housekeeping a great deal can be done to protect workers from
dust for example by widely spacing dust producing
machines by storing dusty materials not in imme-
diate use outside workrooms and by keeping plant
and workiooms as clean as possible preferably with
the aid of vacuum methods of cleaning
The
periodical medical examination of workers now required statutorily in a number of dusty industries is of great value whilst much may also be achieved
by the education of workers in the risks they run
and in their personal responsibility for preventing
and suppressing dust clouds A respirator of good design and with high filtering emciency for low breathing resistance is useful as a secondary line of
defence against dusty conditions
state tr with dusts and particularly when these
are in suspension in all as dust clouds The in crease of Surface area with decrease in constituent
particle size for 4 given weight of dust is striking thus Berger on the basis of certain assumptions shows that the surface of a cube of aluminium
weighing 1 grm is approximately 3 sq cm whereas weighing the cube is comminuted until the thickness of
the resulting lamelle 35 10. coarse staraped powder the surface increases to 429 sq cm Tl the process is continued unal the thickness of the lamella is reduced to 0.6 tfine stamped powdery the surface of the 1 grm of metal becomes 14,2901
cm while for the finest powder prepared industrially in large quantities with lamellas thick
ness 0,3 the surface of a gramme becomes 28.570 sq cm The increase in intensity of explosion of
dust clouds with decrease in constituent particle size ws also of interest in this connection Glwitzky
obtained the following figures from expermental explosions of three types of commercial aluminium pigment powder in a bomb of 53.000 . capacity for two powder concentrations
Particle
size K
12 8.6 0.3
| Duration of Explosion
explosion
sec tor
700 mg
700 mg pet
part part
pressure ) alm
pe
580 mg
:
edi
03
'
0 012
~~ 8.h Ua)
7 9 11.6
The maximum pressure of 11,6 atmospheres for a powder concentration of 580 mg.'l is higher than the maximum pressures recorded for the explosion of gas mixtures including the hydrogen mixture with which 9.7 atmosphere has been obtained Pressures up t ' 18 atmospheres have been recorded for coal dust and flout explosions
at certain concentrations and finenesses Much
greater values still have been measured for starch dast The dangerous potentialities of the finely divided carbonaceous and metalle dusts for fire and
explosion are manifest since factory buildings unlike mines are not capable of withstanding such high pressures and rates of pressure rise For each combustible material there is an upper and a lower limit of concentration and beyond these limits the
material will not burn Within these limits there
is also a minimum temperature or ignition temperature below which the material will not ignite Safety measures against dust cloud hres and explosions therefore aim fundamentally at keeping concentrations outside and in practice usually be-
low the inflammable concentration limity and avoiding sources of ignition and if this should not
be successfully achieved and a fire or explosion should result one should aim at so designing the
plant concerned and arranging the manner of working the process that there is a minimum of damage 10 workers and plant
Electrostatic Charges
is of interest in connection with sources of
ignition
ignition to mention that electrostatic changes are known to be formed when powder issues fromN nozzles or is blown into a dust cloud or rubs frie-
tionally against machine surfaces Belts running over pulleys also accumulate charges Discharges
of such accumulations may ignite dust clouds and although very little is known about this danger it needs to be taken into account Safety measures take the form of keeping the ad as humid as pos
sible or in special cases ionised using electrically conducting belting or suitably earthed collectors and of bonding all plant to earth to prevent accumulation of charges 1 has also been claimed by Wolf that where aluminum foil or powder is prodiced it can be ignited not only by fire and sparks
but also by the effect of light In the case of grinding particularly dangerous
so that the resulting dust concentration is_below is_below
Fire and Explosion Risks
dusts such as magnesium the only safe practice as
the toxic or otherwise harmful limi Such ventilation can take two forms the extraction system
with wall fans removing the contaminated workroom air which is replaced by warmed fresh air
fentering through suitably disposed openings in
* Extracts froin Paper m the " Journal of Spientific Listen-
F
The extent to which protection is needed against the risk of fire and explosion from many industrial
dusts under certain conditions is not generally
realised yet such dust fires and explosions frequently involve serious loss of life and injury to workers and extensive damage to factory premises and plant Examples of dust liable to burn or
to prevent any worker being in the mill 100m whilst grinding is in progress to which end the grinding mill door should be so interlocked with the elec-
rical control to the grinding mill motor that unless the door is shut the gunding plant cannot be set in motion and the door cannot be opened until
the current has been switched off and the mill has
ments March 1912
HM HM Engineorius Inspectoorf Factories
exploite under appropriate conditions are pulverised come to rest
CONVERTOR STEEL CASTINGS
The quality of convertor steel castings depends on the skill of the steelmaker and the grade of raw material at his disposal The regular application of the Sodium Carbonate Process
to cast iron before blowing ensures a low
sulphur content and freedom from objectional
metallic inclusions so that the finished
product possesses a high degree of ductility
and shock resistance Skill is thus enabled to build on a sound foundation
For further information apply to
IMPERIAL CHEMICAL INDUSTRIES LIMITED
LONDON S.W.
CN 1037
A new circulating
FAN for
HEAT TREATMEN
FURNACES
A very strongly made propeller type fan for internat Circulation of high temperature gases and air in various types of heat treat-
ment furnaces
PATENTED
|
FURNACE CIRCULATICIRULNATNG G
Blackman
CIRCULATING
KEITH BLACKMAN ITD MILL MEAD ROAD LONDON N.17
In sheet or cast metals
Expressly designed high for
handling extremely high
temperature gases
WRITE for PARTICULARS TN TOTTENHAM 4522 TA KEITHBLAC
PHONE
LON
INDEX TO ADVERTISERS PAC
J. & Co. t^ PAOX
PAGE
PAGE
2 Roper E A. & Co.
Ltd
2
Core Olls Ltd.
.
7 Jackman W.
o
.
Howland F. E & Co. Ltd
Adaptable Moulding Machina Co.
Coru Products Ltd
Ltd.
_
Jacks William & Co. I.r.
.
Huntless tron Co. Ltd. Tho
Ltil The
Ltd.
ory
A. E. ~/Products Ltd.
Aer graph Co. Ltd Albion Man Rand Co
Alldaye & Dulons Ltd. Allen Edgar & Co. Ltd.
Allen T. Fearmiey & Son . Andern Co. Ltd ..
oe -
o .
20
Cumming W. & Co. Ltd.
Devidson & Co. I.td.
Co.
Ltd.
Jiptingtor Hematite Iron Co. Ltd.
The
,
Chenilraft
Co.
District Chenilraft Co. Ltd. Durrans Janies & Sons Ltd.
9 14 & 8
20
Durrena John & C
Armstrong 312 20 Anglardia Ltd.
Whitworth
Armstrong Whitworth
& Co. Ironfounders
Whitworth
Toula Ltd
.
Aska Wm & On td
Sirw
Sirw Sirw Gi
1.td.
o>
Pneumatic
.
on
Enston & Johnson Johnson Ltd. .Electric Furnace d'^ , Ltd. Elertroomgarts 1 td
Kther Ltd.
~ td
:
Every H. & ~ td oe Byre Smelting Co , Ltd.
Atlas Preservative Co. Ltd.
312
August's Ltd.
.
Railard F. J. & Co. Ltd. 17
Brakhane Ltd. Henry
--
.
ry
Blixton Stove & Steel Truck Co.
1 -1 9 Birmingham Electric Furnaces Ltd.
Risthe Colour Works Ltd
:
& Bradley Foster 1.td.
M. Supplles ltd fladlay A. Co. Ltd Fordath Fngineering Co. Lud
11 .
oe
Foundry & Engineering Co. West
Bronwlchi Itd
Machinery
,
1111 Foundry Plant & Machinery Ltd
Foundry Services Ltd. Fullers Earth Unton Ltd. The
Bradley Thomas & laano Ltd.
HBrriatnissehrtInH sulA ated&CaCb. lesLtL d td. 11-119
British Moulding Machine
British Oxygen Co. Ltd.
Co.
British Pigirons Lid
ws
o
Hrish Rema Manufacturing Co.
Gadd Thos Electric
se
The
General Electric Co td The
1 1 General Galvaulzers It .
General Refractories Ltd. .
Gibbon Bros. Ltd
Ltd.
Gray Thoe B. & Co. Ltd.
Greet Grorge o
o
Guest Keen Baldwins Iron &
:
Steel
std
..
Britan Steelmaker The
Thomson Bouston
AritlahAritlah
2 -Co.
: Co. Ltd
:
.
:
Hammond Alex
(
Willen
Hamer W. Son & Co. Willen
w Land
tall Lid T.
C^
+.
a
Brockhouse Casting- Ltd .. Butterworth Bros. Ltd. Carborundum Co. td The
an
Yih .
Worke
Climax Rock Drill & Eng Worke
Ltd.
Equipment Paundry
Equipment
Coggen Paundry Equipment Ltd
Cohen Hons & Co. Lt George
...
...
Foundry Equipment
Co '
Coleman Commipretal Structur^'s3.td.
12 l
Consett from Co. Ltd.
ae
.e
Constructional Constructional Engineering Co.
Ltd Development
Development
Association
Copper Development Association
22
Baukinn & C^..
Bengal Sand Co. Ltd. The
Herbert Allred Itd
Ltd.
Heywood H. & Co. Ltd.
...
Hill Jones Thop Lid
:
All Patent Haring Co. Ltd.
Holmes W. C. & Co. Ltd
od
Ikord Ltd.
Chemical
Industries
Industries
Imperial Chemical Industries Jurandescent Heat Co. Ltd.
International Alloys ltd .
It^
It^
G
od
10 --
International Furnace Equipment
Co. Ltd.
.
a
+
Keith Blackman Ltd.
Ltd
we
King Uro Stourbridge Ltd
Latstge Co. Aluminous Aluminous Cement LatsgLeatstge
Aluminous AluminoAluuminouss Cement
Co.
,
15
- =
Sk 2
Bugluzera St. Georga'a
Safety Products Ltd.
Ltd
ne
septrlige Coal & Iron Co Ltd
Smith Albert & Co
Labi Trew & Co. Lsd
Langley Alloys Ltd
.
Lavin Loudub td
toyd
FH & Co. Ltd. .
7 '*
2
23 21
i)
=
Streeton John A. Ltd.
Smooth Mig Co.
Sommerke
...
Spencer & Halstead Ltd.
Lord
8. 1.rd.
.
Lukt & Spencer Ltd.
.
[.
Coe
SStpaenrtmoonliInroLntwdorks Co. Ltd. The . a
Macnah and Company Limited ..
Staveley Coat & Iron Ltd.
.
Major Hobiuron & l'o td
wo Steel John
.
:
Mansfield Standard Saud Co. Ltd.
Steels & Cowilhaw ..
an
= Marro Conveyor & Evglucoring Co.
Stein & Atkinson Lt^
a
id
Stein JG Co. Ltd. -
t .
Electrical
Co.
Lu Metropolitan Metropolitan Electrical Co.
Sterling Foundry Specialties
.
22 Sternol Ltd.
+ >
Mkland Bunolithic Furnace Liping Co. Lid The . 1
Stewarts and Lloyds Ltd.
Surrey Industries The
a
Mircles fife karton & Nay td Marlees Watson Co. 1 bd..The
Furnaces and Stoves Ltd.
~
Telen Th : Eqaipment
7
Eqaipment & Ragg co
Thermic Compressor Tiebman's Co. Molhraux Foundry Equipment
Air
Ltd. W
.
:
Moud Nickel Co. Ltd. The
wo
=+ Tilghman's Patent Sand Blast Co. '
Morris
Ltd.
: - dt 1.10
Ltd.
Herbert Ltd. Neild C.
.. Noteutt
P. Ltd
8 Tretmans
L^ ^
@ Tungum Sales Co.
Walter Wharf Co. Ltd
-
Caited Steel Companies Ltd. The -
NortonNorton Grinding Parish
J.
'
on .
Jones & Co
Parker Frederick Ltd.
owe
Paterson Hughes Engineering Co.
28
VViacutgohraR n ay Corporation Ltd
1.1
Pearson
ltd E.
ltd
PkfiHJ. W. C. 3. td Plekford Hulland & Co. Ltd
J'veulco td
C.
.
.
Precision Prenswork Sons Co. Ltd. Precision
,
Ltd.
oe
Prenswork Prace J. Co. Ltd.
:
Rapid Magurtting Machine Co , Ltd.
Revell A Co td
Ltd.
Rihardaun 3 & Son Ltd.
Kidsdale & Co Ind
:
7 Illey Stoker Co. Ltd
.
Rolson Retractories Ltd. ..
Walsall Sandblasting Walsall
Sandblasting
W.
Co. Ward Thow ,
Waring Bros. Warner & Co Iud
Co. Lt.Lt.
.
TThhe e oat
Watson's
Metallurgists Ltd Webster Webster &
Co
Co
SkSkeemmeellddii
Ltd
:
& Bengers 1.ta
. Refining
West Midland Refining Co` Ltd
Co
Wilkinson Thus & Co Lt^"
Wconward Brus & Copeau Laa
50 Workington Iron
Steel
50
= Hranch of T'he United
+81
-
Companus Lt
to war as an
conditions indication
made of raw materials in short supply owing
are advertised in this paper should not be taken
that they are necessarily available for export
eee