IITISH
WITH WHICH IS INCORPORATED THE IRON AND STEEL TRADES JOURNAL
V O L . 73. N o . 1458. J U L Y 27, 1944 rsm«i* Copy 6d. By Po« 8d
I A n n u a l S ubacriptlo»\, H o fr.
Registered at the G.P.O. as a Newspaper* Offices: 49. W e llin g to n Street, Strand, Lonaon, W .C .2 . |_an<j O ve rs ea s, 21 /• (P re p a id .
OULDING ACHINE C ° L TD
F L U X IT O L for Perfect Castings or Ingots C U P O L IN E for Furnace or Cupola
Repairs
E F F IC IE N T service, with consultation RO BSO N REFRACTORIES L IM IT E D
MANSFIELD MOULDING SAND
VERSHAM. KENT.
4 7 . C o n ls c lif f e R o a d , D a r l i n g t o n 'Phono: 2441 'G ra m s : C u p o l l n e
• P U L V E R IS E D R E A D Y F O R U S E I F R E Q U I R E D
A L B IO N (M ansfield) S A N D CO.
t h o s! w. w a r d°l t d. A l b i o n W o r k s , S H E F F IE L O Telephones: S h e ffie ld 76311 ( IS line») M ansfield 3 7 1
M O S T P R O G R E S S I V E F O U N D R I E S USE
D Ê S T R I B O M D
IT IS THE PROVEN substitute for
B E N T O N IT E
^ SOMETHING NEW
^ DEFINITELY NO IRRITATING FUMES
50% S A V I N G I N F U E L
P O W D E R E D C O R E C O M P O U N D
HIGH GREEN STRENGTH— HIGH POROSITY
EASY COLLAPSIBILITY— C A N BE USED W IT H W E T SAND
THE D IS TR IC T CHEM ICAL CO., LTD.
C O M M O N W E A LT H HOUSE, 1-19, N E W O XFO R D STREET, L O N D O N , W .C .I
A N D F O U N T A IN H O U S E , 81 F O U N T A IN S TREET, M A N C H E S T E R , 2
See
W I C K E L * 0 V
l r t i s e m e h t
Pneulec C U P O L A S
T H E CUPOLA W I T H TUYERES PLACED B E L O W IN STEAD
. .. . OF IN S ID E T H E B E LT
B u ilt by
PN E U LE C L T D ., S M E T H W IC K , N r . B IR M IN G H A M
STEEL WÖÄKS PLANT
A D A M S O N - A L L I A N C E
CO. LTD .
165 F E N C H U R C H S T R E E T , L O N D O N , E.C.3. W orks: Alliance, O h io , U.S.A., and Hyde, Cheshire
J O S E P H A D A M SO N & C O . L TD ., P .O . Box 4, Hyde, Cheshire.
M a n u fa c tu r e r s o f B o ile rs o f e v e ry d e s c r ip tio n , P re s s w o rk . ,C ra n e s ,, W e * : '- ? W n r i
FOUNDRY TRADE JOURNAL
JU L Y 27, 1944
BIRLEC 3-phase, direct arc L E C T R O M E L T F U R N A C E S are now installed in many foundries fo r the production of BLAC K H EA R T MALLEABLE
iron by cold melting or by duplexing.
The furnace illustrated is rated at 600 kw. and has a capacity of 15 cwt.
BIRMINGHAM ELECTRIC FURNACES LIMITED
E R D I N G T O N • B I R M I N G H A M 2 4 .
T E LE P H O N E — EASt 1471 (9 Linei).
T he f a c t th a t goods m a d e o f r a w m a te r ia ls in s h o rt s u p p ly o w in g to w a r c o n d itio n s a re a d v e rtis e d in th is p a p e r sh o u ld n o t be ta k e n as an in d ic a tio n t h a t th e y a re n e c e s s a rily a v a ila b le f o r e x p o rt
FOUNDRY TRADE JO U R N AL J U L Y 27, 1944
There are over 1 ,0 0 0 sep arate bits and pieces in a m odern gun o f 1 944 a s a g a in st th e h a lf d ozen or so in th e early brass ca n non o f 1344. A nd yet th ese m odern w eapons h a v e to be produced at a speed th a t w ould h o v e staggered the old can non fou nder. O xygen plays an im p ortant part in this speed -u p , fro m s te e l- m a k in g to cu ttin g o u t and w eld in g m an y o f th e com plicated parts. T he variou s processes o f m a n u fa c tu r e need oxygen and oxygen needs cylinders. A nd so , a s cylinders m u st be kept in circu la tio n , p lease h a v e yo u r em pties ready for collection w hen our lorries call.
r THE BRITISH OXYGEN COMPANY LIMITED
L O N D O N & B R A N C H E S
,,ł* J U L Y 27, 1944 FOUNDRY TRADE JOURNAL 5
\
. . * T a e power-loading o f thefuture aeroplane will be revolutionary — more and more, light alloys w ill cut the weight whilst adding to the strength. New achievements are daily made possible by these new materials. Higher speeds, higher carrying capacity, stronger structure— in all these ways, 'IN T A L*, makers o f the f n e s t aluminium alloys, will be proud to help.
6 FOUNDRY TRADE JO U R N AL J U L Y 27, 1944
o u t ) « A t e s c . . .
Single stroke, chain driven mobile eggnogger.
m r n !
G E O R G E COHEN, Sons & Co., Ltd.
Scrap Merchants since 1854 * Broadway Chambers, Hammersmith, London, W.6 {Riverside 4 1 4 1 )
Quadrant St., Canning Town, E.16 {Albert Dock 3104) • 6oo, Commercial Rd., E.14 {Stepney Green 3 4 3 4 )
And at Sheffield, Birmingham, Manchester, Newcastle, Belfast, Swansea
ONE OF THE
600 GROUP
Oj COMPahih
J U L Y 27, 1944 FOUNDRY TRADE JOURNAL
W A L L W O R K G E A R S L I M I T E D
F O U N D R Y E Q U I P M E N T D E P A R T M E N T
O C E A N I C H O U S E , l a , C O C K S P U R S T R E E T , L O N D O N , S.W.I
| Telephone: W hitehall 8 051/2/3 Te l e g r am s : W a llw o r k O c e a n illa Lesquare L o n d o n
8 FOUNDRY TRADE JO URNAL J U L Y 27, 1944 j j
IrvlWiWV»
P i g in t he r a w
W h a t w ith ores n o t b ein g w h at th ey w ere an d coke v a ry in g in q u a lity , th e lo t o f th e p ig iro n m a n u fa c tu re r is a p t to be h a rd . T h e s u lp h u r d e m o n is e v e r- p re s e n t an d tig h te n in g his h o ld : h e m u s t be even m o re s te rn ly e x o rc ise d if y o u a re to b e p ro u d o f y o u r pig. S o d iu m C a rb o n a te is th e g re a t a n ti- s u lp h u r a g e n t. O p e ra te y o u r b last fu rn ace fo r m a x im u m o u tp u t an d d e s u lp h u ris e in th e la d le w ith d e n se s o d iu m c a rb o n a te . T h is is th e m o d e rn m e th o d , p ro v e d fa r s u p e r io r to th e
c o n serv ativ e p ro c e d u re o f k eep in g d o w n s u lp h u r c o n te n t b y u sin g a large q u a n tity o f lim esto n e in th e fu rn a c e c h a rg e . S ir, d o n o t let y o u r p ig ru n w ild — c o n siste n t, b e tte r q u a lity p ig is so easy a n d so econom ical if you m ake use o f th e S o d iu m C a rb o n a te p ro c e ss.
I M P E R I A L C H E M I C A L I N D U S T R I E S L I M I T E D
U N . U u
JU LY 27, 1944 FOUNDRY TRADE JOURNAL 9
TITAN CORE MACHINES
are daily solving new core-making problems
and r e m o v i n g b o ttle-n ecks in war production
T H E
T e le p h o n e : M ID 4 7 5 3 -4
ENJGTNFERING C9 UP
T I T A N W O R K S B I R M I N G H A M , 12
T e le g ra m s :
" S tru c tu ra l B irm in g h a m ”
Saving in Skilled Labour,
A girl can operate the Titan machine. Intricate cores may be blown in one operation (one movement of the hand lever).Faster O u tp u t.
Up to tenfold increase over hand methods.Better Cores
of uniform quality, greater strength and maximum permeability.The machine illustrated is fitted w ith a sand co ntainer of 75 lbs.
capacity (which can be re charged in a couple of minutes) m o to r-d riv e n sand ag itato r and autom atic compressed air h o ri
zontal clamp. This machine takes boxes up to 20 ins. long by 12 in. w ide by 24 in. high w ith o u t rem oving the clamps.
EARLY DELIVERY
Provided motors for standard current are required, we can offer early delivery of machines of the above type for work of certified priority.
Ask f or Folder 204
FOUNDRY TRADE JO U R N AL J u ly 11
.
1944" f e w ® , B
C o r e on
T h e
for I R .O N castin gS
, T t a
s » « » " S S * ■ * ? £ > * *
s 0 H s c »
i j v W V t S - ; lL l^
J «tv \ N O ^ S * , nd 57 P V 4<£N '*
Kan«* T l
JU LY 27, 1944 FOUNDRY TRADE JOURNAL II
S A N D S L I N G E R S
F O R E X P R E S S R A M M I N G
Sandslinger on Power-driven Truck— Gear enclosure removed.
Illu s tra tio n sh o w s S a n d s lin g e r w ith 12 ft. ra d iu s a r m —c a p acity 5 cubic ft.
of ra m m e d sa n d p e r m in u te . U n it can m ove fro m p o in t to p o in t a t cran e speed an d is u sed fo r r a m m in g la rg e m o u ld s an d c o res fo r all classe s
of c a s tin g s .
FO U N D RY PLA N T & M ACH IN ERY LTD. Il3'
g l a rs g o w t s t12 FOUNDRY TRADE JOURNAL J U L Y 27, 1944
F o r O ven s and F u rn aces o f all Sizes
B r it is h “ R e m a ”
PULVERIZED FUEL FIRING EQUIPMENT
The illu stratio n shows a typical self-contained feeding and firing equipm ent using pulverized fuel from a main storage bunker. Suitable for use w ith all types of furnaces or other installations.
Any num ber of separate firing points m ay be employed w ith complete individual control.
C o m p l e t e I n s t a l l a t i o n s S u p p l i e d
B R I T I S H “ R E M A ”
MANUFACTURING CO., LTD.
(P ro p . : E dgar A llen & C o., Ltd.)
I m p e r i a l S t e e l W o r k s S H E F F I E L D , 9
F .T .J .
A S E A ELECTRI C
P U L L E Y B L O C K S
T he robust totally enclosed construction and close lift make the ASEA electric pulley block the best handling equipm ent for foundry use. Its range of usefulness is almost unlimited throughout the various foundry departments, for instance : Cupola feeding (block arranged with fast
lift).
Handling core boxes and pouring (block fitted with inching attachment giving 5 control to '02").
Knocking out cores and fettling (as illus
trated).
Loading the finished castings for despatch.
( We will gladly send particulars on request.
A S E A E L E C T R I C L I M I T E D
{Associated with Fuller Electric & M anufacturing-Co. L td .) H E A D OFFICE : FU LBO UR NE R O AD , W A L T H A M S T O W ,
L O N D O N , E. 17 ' Telephone : Larkswood 235 0 (10 lines)
'Telegraph : A utosyncro, T elex, London
J U L Y 27, 1944 FOUNDRY TRADE JOURNAL 13
:rCOMPRESSORS ‘ PNEUMATIC TOOLS• ELECTRICTOOLS• DIESEL ENGINES VACUUMPUMPSCONTRACTORS EQUIPMENT • ROCKDRILLS DIAMONDDRILLS OILWELLTOOLS
14 FOUNDRY TRADE JO U R N AL J U L Y 27, 1944
W O R L D F A M O U S
FOR HIGH QUALITY AN D QUICK DESPATCH IDEAL FOR NON-FERROUS METALS
TELEGRAPH OR TELEPHONE
MANSFIELD ST A N D A R D
GOLD MEDAL
MOULDING SA N D
M A N S FIE LD S T A N D A R D SA N D C2. L IE
M A N S FIE LD ,
E N G L A N D . P U L V E R IZ E D OR U N M IL L E D AS R E Q U IR E D TEL. 201—2
r ■ i i*.r —iii.-é!, i T.fii v ii'h i vrï
DAYLIGHT'S CLOSEST RIVAL
T o improve the health and the efficiency of workpeople on essen- t‘a^ war production, to increase V output, they need natural daylight
» to work in. W here th a t’s im possible, the next best thing is daylight’s closest rival —“ s i e r a y” Fluorescent T ubular Lighting. This proved system of industrial lighting cuts out interfering shadows, throw ing a perfect, even working light over the whole workshop. T h ere’s a big saving too — in current. Siemens “ Sieray” Fluorescent T ube is approximately three times as efficient as an ordinary gas filled lamp of comparable wattage.
F R E E A D V I C E — A Siemens industrial lighting specialist will, w ithout obligation, advise on existing lighting systems. H e m ay be able to suggest improvements which possibly w ill save current charges an d the N a tio n ’s Fuel.
F L U O R E S C E N T T U B E
” Oke, V a / i d s t i o k o j G o o d £ ¿ q kU * iq ‘
S IE M E N S E L E C T R IC L A M P S & S U P P L IE S L T D ., 38/39, U pper Tham es Street, London, E .C.4
; 'Ł
É S m
J U L Y 27, 1944 FOUNDRY TRADE JOURNAL 15
For w h a te v e r purpose you are using heat — steam raising, fo u n d ry w o rk , o r m etal tr e a t m en t, satisfactory o u tp u t is d e p en d e n t on th e g rea test econom y. Both in ex tra c tin g th e utm o st fro m lim ite d fu el, and increasing prod uction th ro ug h th e co m p lete c o n tro l o f te m p e ra tu re and conse
q u e n t lack of “ spoils,” M ir r - lees s to k e r installations are proved th eso u n d es t econom y.
T h e y ’ re available now .
y o I I i t <L> P tf/ i t /V O W
H E A T W IT H E C O N O M Y
C O M B U S T IO N E E R A U T O M A T IC STOKERS
g u a r a n t e e e c o n o m ic h e a t
M IRRLEES B IC K E R T O N & D A Y L TD .,
H A Z E L G R O V E : S T O C K P O R T : C H E S H I R E
T H E M IRRLEES W A T S O N CO. LTD .,
S C O T L A N D S T R E E T :: G L A S G O W , C .S
M e m b e rs o f th e U n d e rfe e d S to k e r M a k e rs ’ Association
d m 1103
w it h WHICH IS INCORPORATED T H E IR O N A N D S T E E L T R A D E S /O U R N A L
4 9 , W e llin g to n S tre e t, London , W .C .2 .
W A R T IM E A D D R E SS to which all com m unications should be sent I __
3 , A m e r i h a m R o a d , H I G H W Y C O M B E , B u c k r.
'G ra m s i “ Zacatecas, High W y c o m b e .”
’ Phone i H IG H W Y C O M B E 1792 (3 lines).
P U B L IS H E D W E E K L Y i 21s. p e r annum (H o m e and O v e rs e a t)
O F F IC IA L O R G A N O F i
C O U N C I L O F I R O N F O U N D R Y A S S O C I A T I O N S C h a irm an I F ltz H e rb e rt W r ig h t , T h e B u tte rle y C om pany R ip ley , near D e rb y . S ecretary I V . D e lp o rt, 2 , C a x to n S tre e t, W e s tm in s te r, S .W .I.
P articipatin g Associations i B ritish Bath M a n u fa c tu re rs ’ A ssociation ; B ritish Iro n fo u n d e rs ’ A ssociation ; B ritish M a lleable T u b e Fittings A sso ciation; C ast Iro n A x le b o x Association ; Cast Iro n C h a ir Associa
tio n ; Cast Iro n H e a tin g , B o ile r and R a d iato r M a n u fa c tu re rs ’ Association*
C ast Iro n S egm ent A ssociation ; G reensand Pipe Founders’ Association o f S cotland; Iro n fo u n d e rs ’ N a tio n a l C o n fe d e ra tio n ; N a tio n a l Associa
tio n o f M alleable Iro n fo u n d ers ; N a tio n a l In g o t M o u ld Association ; N a tio n a l Iro n fo u n d in g E m p lo y e rs ’ F e d e ra tio n A s so ciation o f A u to ^ m o b ile and A llie d H ig h D u t y Ir o n fo u n d e r s ; B ritish C ast Iro n Research Association (a ffilia te d ); B ritish G r it A s s o c ia tirn ' (a ffilia te d );
Flushing C is te rn M a k e rs ’ Association (a ffilia te d ) ; In s titu te o f B ritish F o u n d ry m e n (a ffilia te d ). _____
I N S T I T U T E O F B R I T I S H F O U N D R Y M E N P R E S ID E N T , 194 3-44 : D . S h a rp e , F o u n d ry P la n t & M a c h in e r y , L td . 113 W e s t R e g e n t S t r e e t , G lasgow .
G en e ra l S ecretary i T . M akem son. A c tin g S e c re ta ry , J. B olton Saint John S tre e t C ham bers, Deansgate, M anchester 3.
BRANCHES
Birm ingham , C o v e n try and W e s t Midlands t A . A . T im m in s, F .I.C 3 3 . C a r te r s L a ne, Q u in t o n . B ris to l and W e s t o f E n g la n d : A . H ares, 2 0 , G r e e n b a n k R o a d , H a n h a m , B ris to l. E. Midlands i S. A . H o rto n ” T h r e e ,” M ostyn A v e n u e , L lttle o v e r, D e rb y . Lancs : H . B u c k ley, E lle s m e re , N o r f o lk A v e n u e , B u rn le y . London : V . C . F a u lk n e r, 3, A m ersham Road, High W y c o m b e . M iddlesbrough (pro tern.) j J. K . S m ithson, N o rth -E a s te rn Iro n Refining C om pany, L im ite d , S tillln g to n , S to c kton-on-Tee s. N e w ca stle-u p o n -T y n e : C . Lashly, S ir W . G . A r m s trong, W h it w o r t h & C o . (Iro n fo u n d ers ), L td ., Close W o rk s , G ateshead.
Scottish i J. Bell, 60, St. Enoch Square, Glasgow. Sheffield : T . R. W a l k e r , M .A ., English S te e l C o r p o r a tio n , L t d ., S heffield. W a les and M o n m o u th i A . S. W a ll, 14, P alace A v e n u e , L lan d aff, C a rd iff. W e s t Riding o f Y o r k s h ir e : D ouglas Jepson, M .S c., 9 , A m b le sid e A v e n u e , B ra d fo rd . South A fric a : B. P. S k o k , M utual Building, Johannesburg.
S E C T IO N S
B urnle y i H . Buckley, E llesm ere, N o rfo lk A v en u e. B u in le y , Lancs.
Cape] T o w n : K . Z w a n z l_ e r, P .O . Box 346, Cape T o w n , S. A fric a . East À ngllan i A . N . S u m n e r, 5 1 6 , N o r w ic h R oad, Ipswich F a lk ir k : T . R. G o o d w in , ” V le w fie ld ,” F a lk irk Road, Bonnybridge. Lincoln i E.
R. W a lte r , P h .D ., T h e Technical C olleg e, Lincoln.
A S S O C I A T I O N O F B R O N Z E A N D B R A S S F O U N D E R S P r e s id e n t : H . Blssell, J. S to n e & C o ., L td ., L o n d o n . S e c re ta rie s : H e a th c o te & C o le m a n , 2 5 , B e n n e tts H ill, B irm in g h a m , 2
T H E I N S T I T U T E O F V I T R E O U S E N A M E L L E R S President : W . H . W h it t le , W . H . W h it t le , L im ite d , Eccles, near M anchester. C h a irm an i W . T o d d , P ark inson S tov e C o ., L td ., Stech- fo r d , B irm in g h a m . H o n . Sec. : W . T hom a s, A .I.C ., Bank H ous e , H ig h S tr e e t, R ic k m a n s w o rth , H e rts .
F O U N D R Y T R A D E S ’ E Q U I P M E N T A N D S U P P L I E S A S S O C I A T I O N
P resident I G . E. France, A u g u s t’s, L im ite d , T h o rn T re e W o r k s , H a lifax . H o n o r a r y S e c r e ta r y : K . W . Bridges. A ssistant S ec retary i Miss L. C o x , 5 2, S u rbiton H ill P ark , S u rb ito n , S urrey.
W E L S H E N G I N E E R S ’ A N D F O U N D E R S ' A S S O C I A T I O N P resident i W . E. C le m e n t, C .B .E ., M orfa F oundry, N e w D o c k , Llan elly.
S ec retary t J. D . D . Davis, I , St. James G arde ns , Swansea.
B R I T I S H C A S T I R O N R E S E A R C H A S S O C I A T I O N A lv e c h u rc h , B irm in g h a m . ’P hone and ’ G ra m s : R e d d itc h 7 1 6 . S c o ttis h L a b o r a t o r ie s :— F o u n d ry T e c h n ic a l In s t it u t « ,M e e k ’ s R o a d , F a lk ir k . (P h o n e i 33Z ?
16 FOUNDRY TRADE JOURNAL JU L Y 27, 1944
T h e n ee d fo r all p o s s ib le c o n s e rv a tio n o f m a n p o w e r ; th e d e m a n d fo r th e m a x im u m o u t p u t o f v ita l c a s t m e ta llic p ro d u c ts ; th e in s iste n c e u p o n th e lo w e s t c o s t o f p r o d u c tio n ; a n d th e n e c e ssity o f m a in ta in in g , a n d ev e n im p ro v in g , th e q u a lity o f th o s e p ro d u c ts .
A ll th e s e c o n d itio n s c o m b in e to p o i n t to th e o n ly s a tisfa c to ry s o lu tio n to all th e s e p ro b le m s —
b u t it m u s t be m e c h a n is a tio n p a r tic u la rly c o n s id e re d , d esig n ed a n d a d a p te d to th e in d iv id u a l s ite c o n d i t i o n s ; to th e p a r tic u la r p r o d u c t ; a n d w ith fu ll re g a rd to
a llth e fa c to rs , e c o n o m ic , g e o g ra p h ic a l an d h u m a n , w h ic h m ay h av e any b e a rin g o n th e p ro b le m .
In o th e r w o rd s c o n s u l t :—
“ The Specialists in Foundry M echanisation”
M E C H A N I S A T I O N
w h o se p ro d u c ts
“ Set the Standard b y which Foundry Plant is ju d g e d .”
L IM ITE D
’Phones : 6 1 2 4 7 & 8
H A L I F A X , E N G L A N D
’C ra m s : August, H a lif a x Sole Licensees a n d manufacturers for British Empire (excluding C a n a d a ) of the Simpson S a n d MixerFoundry Trade J o u r n a l,lu ly 2 1 , I 944
established /$02
W IT H W H IC H a IF K O V O M T E D THE IRON AND STEEL TRADES JOURNAL
Vol. 73 Thursday. July 27, 1944 N o . 1458
A Splendid Lead
W h eth er B irm id In d u s trie s, L im ited , have been a little p re m a tu re in th e lau n c h in g o f a cu t-an d - dried a p p re n tic e s h ip schem e is d e b a ta b le , in view of the g en eral ch an g es as envisaged by th e E d u c a tion Bill n o w b e fo re the H o u se o f L o rd s. T h e scheme is set o u t in a w ell-illu strated b ro c h u re from w hich all w a rtim e activities h av e been speci
fically excluded. T h e re a re m a n y fe a tu re s in the scheme, w hich is b ased o n a five-year perio d , o f a wholly sa tisfa c to ry c h a ra c te r. O u tsta n d in g a m o n g st these is a flexibility w h ich allow s the “ b rig h t ” apprentice n o t to en d by b ein g a tra d e sm a n , b u t a technician q u alified to o ccupy th e m o st p ro m in e n t position o n th e ex ecu tiv e staff. By lim iting the dates o f en try to th re e fixed tim es each y e a r, an attem p t is m a d e in itially to stagger h o lid ay s an d to facilitate th e ac tu a l o rg a n isa tio n o f th e shops.
Because B irm id In d u strie s is to -d ay such a very large o rg a n isa tio n , it c a n offer a w ide ran g e o f trades an d executive p o sitio n s. I t h as a lre a d y m a d e arran g em en ts w ith th e S m eth w ick M u n icip al School to give th e necessary th e o re tic a l in stru c tio n . The sch em e envisaged is essentially a san d w ich course, em b ra c in g th re e term s, tw o o f w hich are spent in th e w o rk s a n d one a t sch o o l, w here a th irty -h o u r w eek te c h n ic a l co u rse is to be p r o vided. T h is w ill e n a b le c u ltu ra l activities to be u n d ertak en a n d , w h a t is to o u r m in d m o st im p o r
tant, to e n ab le ev en in g class study to be u n d e r
taken th r o u g h o u t th e p e rio d . I t p resen ts a n ideal m eans fo r d e te rm in in g w h ich a p p re n tic e s a re su it
able fo r receiving specialised tra in in g an d w hich can be safely re g a rd e d as b ein g the m ak in g s o f good c raftsm en . T h e legal ag reem en t, w hich is set o u t in the b ro c h u re , is co u ch ed in term s easy o f u n d e rs ta n d in g by th e a v erag e y o u th . It insists on a few essentials, a n d it w o u ld be as w ell if th e ap p re n tic e sh ip m a s te r w ere to issue a set o f a d d i
tio n a l “ h in ts ” to n ew -co m ers, co v erin g p e rso n a l hygiene, safety m easu res an d th e d an g ers boys usually e n c o u n te r w hen e n te rin g a large industrial estab lish m en t, o f w hich g am b lin g is not the least.
T h e rew ard s offered by the schem e set o u t are ex trem ely attractiv e. T h e b rig h test boys are
p ro m ised a c o u rse a t th e F o u n d ry School, o r at th e U n iv ersities o f L o n d o n o r B irm ingham . T h e idea o f p resen tin g all this in fo rm a tio n in a n illus
tra te d b ro c h u re is specifically d esigned to c a p tu re th e im a g in a tio n o f schoolboys. T h is is n o w ad ay s re g a rd e d as essential, as som e o th e r com petitive in d u stries c a rry th eir ow n very superficial g lam o u r. T h o u g h th is b o o k le t is in ten d ed fo r th e y o u th s living n e a r to th e w o rk s, w e a re su re th a t B irm id In d u strie s w ill m a k e it av ailab le fo r m a n u fa c tu rin g co n cern s w hich a re now th in k in g a ro u n d the sam e subject. P ro v id ed th a t th e schem e satis
fies th e p ro v isio n s o f th e new E d u c a tio n Bill, w hich w e believe it does, th e n th e re is presented to th e m etallu rg ical in d u stries a clea r-cu t case of h o w th e fo u n d ry can en su re an a d e q u a te supply o f staff, b o th o f th e skilled w o rk m a n a n d ex ecu tiv e type, in th e p o st-w ar p erio d . M o reo v er, b o th types a re c a te re d fo r in th e sam e schem e, w hich to o u r m in d is a n excellent featu re.
According to a statement issued by the Geological Society of London, the total num ber of British geologists wholly engaged in a professional capacity in pre-war years was probably less, than 600, nearly one- quarter of whom were occupied in the teaching of the science, principally in the Universities. To some extent this high proportion of geologists engaged in academic spheres is due to the fact that large classes of technical students in mining, metallurgy, civil engineering, and agriculture require tuition in geology as a part of their professional training. Within two years after the cessation of hostilities it seems likely th at considerably more than 100 recruits will be called for to fill gaps and augment the ranks of professional geologists.
Contents
4. S plendid Lead, 247.—C e n trifu g a l C astin g M ethods, 248.—
Iro n fo u n d ry F u el N ews—X I I I , 248.—S an d slin g er M oulding P ra c tic e , 249.—T he Use of B o u g h t C ast-Iro n Scrap in the .fo u n d ry , 254.—M essersch m itt H ead er T an k , 255.—C orrespond
ence, 257.—B ritis h S ta n d a rd s In s titu tio n , 257 —M ould and Core Surfaces a t P o u rin g T e m p eratu res, 258.—M echanical H a n d lin g in F o u n d ries, 259.—N ews in B rief, 262.—P erson al, 262.—O b itu a ry , 262.—C om pany R esu lts, 264.—R aw M aterial M ark ets, 266.—W ag es of AVelders an d D ressers in Steel F o u n d ries, 266.—New C om panies, 266.
248 FOUNDRY TRADE JO U R N AL J U L Y 27, 1944
CENTRIFUGAL CASTING METHODS
Centrifugal casting is used in cases where soundness and cleanliness of metal are required. Na t h a n Ja n c o
describes m odern practice in the “ Iron Age ” for M arch 30. The methods used in the industry are divided into three different types. The first is true centrifugal casting such as is used for bushes and liners. A centre core is not used and the direction of solidification is from the outside of the casting towards the axis of rotation. The second is semi-centrifugal casting such as is used for odd shaped castings.w hich are spun about their own axis, but which have cooled in two directions rather than in one direction only.
The third m ethod is called the pressure method of centrifugal casting in which the castings are arranged about the centre o f rotation like the spokes of a wheel.
According to the article, the equipm ent used in cen
trifugal castings falls into two general classes, those with vertically rotating moulds and those with hori
zontally rotating moulds. The former are generally used when the diam eter of the casting is large com pared with the length, or when the semi-centrifugal or pressure methods are used. The metal yield by these m ethods varies from 60 to 100 per cent., depending upon the type of casting and the gates required. H ori
zontal machines are used for castings in which the length is great as compared to the diameter, and in which the bore is cylindrical in shape. The metal yield obtained is approxim ately 100 per cent.
Both sand moulds and perm anent moulds are used for centrifugal castings. The form er are used where the outside shape of the casting does not perm it a metal m ould to be used or where only a few castings are required. Perm anent moulds are usually made of iron, steel or graphite, the m ost popular material being an alloy cast iron of about 2 2 tons per sq. in. tensile strength. The moulds must be free from defects, especially at the surface which contacts the casting, and it must be well balanced about the axis of rota
tion. Generally, the use of a refractory wash, uni
form ly sprayed on to the hot mould, increases the life of a perm anent mould. Metal moulds are usually preheated to 150 to 200 deg. C. before casting to ensure that they are perfectly dry. H igher pre-heat tem perature may be used in some cases to avoid laps or cold shuts.
Casting Temperatures
Higher casting tem peratures are used for centrifugal castings than for static casting, especially when metal moulds are used. The rate of pouring and the spin
ning speeds used are very im portant and considerable data are given.
The absence of gates or risers in centrifugal casting simplifies the operation and makes for improvement generally. On the other hand, this type of casting has defects of its own which m ay not occur in static casting. F o r instance, if the spinning speed of a horizontal mould is too low, or the metal is poured in too fast, “ raining ” will occur. M etal falls from the top of the m ould to the bottom, oxidising as it does so and causing bad castings or an excessive am ount
of dross in the casting. The “ raining ” occurs because the metal has not been accelerated to the speed of rotation of the mould. Longitudinal cracks in cast
ings may be prevented by reducing the spinning speed so that the hoop stress does not exceed the hot strength of the casting. Flanges at the end of castings cause circumferential cracks by preventing longitudinal con
traction, unless moulding sand of low hot strength is used. Holes on the outside surface of a casting are usually caused by water or volatile m atter present in the sand. Pits on the inside of a casting occur when the proper conditions necessary for directional solidifi
cation from the outside towards the axis of rotation do not exist. This may be caused by the m ould being too hot at the start, by air circulation through the core of the casting, or by the casting wall being too thick.
The remedy in the latter case may be to use a metal mould, reduce considerably the pouring rate of the last half of the metal, or to introduce into the bore of the casting after pouring an insulating m aterial or pipe eliminator, which m ay be of an exotherm ic type in extreme cases.
IRO N FO U N DRY FUEL N EW S—XIII
N ext to the cupola, the biggest fuel-consum ing unit in the ironfounding industry is the drying stove, and founders operating m ould and core-drying stoves should therefore be sure that the process is carried out efficiently. As the am ount of fuel required to dry or bake a ton of sand cannot readily be fixed within a certain range as can the am ount of coke needed to melt a ton of iron in the cupola, it may well be that num bers of ironfounders do not realise that their stove drying is not as efficient as it might be. It is therefore intended to m ention in the next few articles in this series a few points which, from the experience of the R egional Panel m em bers of the Ironfounding Industry Fuel Com m ittee, should help in reducing fuel consum ption.
As when investigating the efficiency of any other fuel-consuming process, the first step is to know exactly how much fuel is being used. The am ount of, say, coke delivered to the stoves over a certain period will, of course, be know n, but an .endeavour should also be m ade to record weekly the am ount used by each stove. It is not always convenient to do this by weighing, but a very good estimate can be made by carefully recording the num ber of barrowsful taken to each firebox." Incidentally, it is interesting to note that some firms have found that very definite savings have resulted simply from this measurem ent o f the fuel being used, all other factors having apparently been unchanged!
Multi Metals, Limited, is being wound up volun
tarily. Mr. W. J. W att, 20, Essex Street. London W.C.2, is the liquidator.
Mr. A. V. Alexander, First Lord of the A dm iralty has rejected the Tyneside conference com m ittee’s p ro posal that two shipyards at Jarrow and W allsend should be reopened.
J U L Y 27, 1944 FOUNDRY TRADE JO U R N AL 249
SANDSLINGER MOULDING PRACTICE*
By W. Y. BUCHANAN
All moulding operations require the ram ming of a quantity of sand into a space of irregular shape with the object of producing a uniform degree of ram ming on all surfaces of the pattern. This is usually neces
sary also throughout the body o f the m ould itself, although occasionally there is some attem pt to pro
duce higher perm eability in the centre of ram med masses of sand em ployed in moulds or cores. This improvement in perm eability is theoretically obtained by lighter ram ming in parts away from the m ould’s face, but this is usually obtained m ore in theory than in practice.
There are several well-defined methods of obtaining the desired results in moulds and cores, for example:—
(a) Hand ram ming; (b) jolt ram ming; (c) squeeze ram ming; (d) blowing; and (e) Sandslinger. The last method is under consideration here.
Hand Ramming
Hand methods have certain fields of application and also certain limitations. H and ram ming, when well done, consists of the ram ming of small quantities of sand at a time, using a ram m er of small surface area, which can be directed into very restricted spaces. The rammer head, i.e., the flat or rounded area at right angle to the direction o f the ram m ing force, is always kept covered with a surplus of sand during the opera
tion, and the ram m er is progressively lifted so as to incorporate more and more loose sand into the body of ram m ed sand in the m ould or core.
Under ideal conditions the results by this m ethod should be very good, but the m ain objection to hand ramming is that the results depend entirely on the diligence of the w orkm an and to a less extent to his skill, particularly in green-sand work. Moreover, the work is laborious and slow. Then, again, the process of ram m ing with a m etal ram m er, no m atter how small its ram ming surface, tends to make a series of little partings which can actually be demonstrated.
This in turn gives considerable variations in degree of ramming or mould hardness from below the ram mer face to the position of the ram m er face at the last blow.
A nother defect in this m ethod of ram ming is that if the sand be ram m ed too near the pattern, this local hardness already described is a very fruitful source of sand defects, such as scabs, constituting one of the few definite causes of scabs. Similarly, uneven ram ming through the ram m er being moved at too big intervals results in swelling of the casting due to liquid pressure, producing a wavy surface which is particu
larly undesirable in most types of castings left un
machined. The m ain advantage is that the first cost
• Paper read a t the F o rty-first A nnual M eeting of the In stitu te of B ritish Foundrym en. The Author is F o u n d ry M anager, Joh n L an g
& Sons, L im ited .
The Sandslinger as a general- purpose machine
of the ram ming m achinery is precisely nil and, of course, readily portable. H and ram ming has, of course, a long record of generations of successful application, which cannot be lightly set aside in any purely technical discussion.
Jolt Ramming
Jolting consists of raising the mould or corebox filled with sand and allowing it to fall under the in
fluence of gravity, thus obtaining a sudden jar on impact of the lifting table with the solid base of the machine. This action produces a movement of the loose sand towards the surface of the base on which the im pact takes place.
W hen the surface of the pattern is horizontal, con
ditions for effective ramming are ideal and the effec
tiveness of jolting becomes less as the angle of the pattern changes towards the vertical. Ramming on vertical surface is therefore obtained as a result of that property of sand known and measured as flowa- bility.
Re-entrant angles are usually avoided because of the necessity of drawing the pattern from the sand, but where they have not been blocked out, such projec
tions of the m ould itself cannot be ram med without special procedure of a nature entailing hand ramming of this particular part of the box. For example, in ramming the top-part moulding box having bars of the usual vertical shape, the finished top part shows lines of softness under each bar.
This can only be prevented by hand ram ming either before jolting or after finishing jolting. This finishing operation takes more time than the jolting itself. This method of ram m ing tends to give a greater hardness on the flat parting or wide horizontal surfaces of the pattern with a gradual reduction of the degree of ram ming from the surface upwards. F or this reason flat top parts of considerable area are always difficult to jolt-ram owing to the tendency for large surfaces of the m ould face to drop out.
This defect is encouraged by low green-strength.
while at the same time higher green-strength is often accom panied by poor flowability under these condi
tions. Jolting is, of course, very successfully applied to small flat work, particularly where the boxes are carried off by hand and also to larger boxes where the contour of the pattern is followed out to some extent by specially shaped bars.
The defect is not nearly so troublesom e in dry-sand moulds, for these are invariably finished and handled in all subsequent operations with the parting upwards in such position the tendency to softness behind the m ould face may assist venting, and is therefore very desirable, provided it stops short of allowing swelling.
At the same time, the tendency to swelling is not troublesome in moulds which are subsequently dry.
250 FOUNDRY TRADE JOURNAL J U L Y 27, 1944
Sandslinger M o u l d i n g Practice
Squeezing
Squeezing is applied to relatively small boxes because of the high total pressure required. W hen the force is applied from the top of the mass of sand, the degree of packing tends to decrease in a downward direction, resulting in soft ram ming, particularly in small pockets in the pattern face. The best results are obtained on light castings of a flat nature, which can be made in very shallow boxes.
The depth of the box which can be ram m ed by squeezing is therefore limited to little m ore than 6 in. with plain patterns and even less in certain cases.
Squeezing machines, because of the very simple opera
tion, i.e., probably only one m ovem ent of the piston in the making o f each part, last a long time w ithout needing m ajor repairs, in contrast to jolting machines with their very rapid movements.
Squeezing cannot conveniently be applied to boxes having ribs or bars, and a considerable strength is required in the box part itself to prevent sides being pushed outwards by the force of the squeezing action.
This results in a robust design of boxes, at the same time increasing their weight.
A com bination of jolting and squeezing is very successfully applied on small boxes, particularly where even ram m ing on the m ould face is obtained by jo lt
ing, and the tendency to softness in the upper part of the m ould corrected by squeezing after jolting is completed. W here the depth of the box does not exceed 7 or 8 in. a fairly uniform degree of ram ming can be obtained throughout the com plete section.
This com bination of squeezing and jolting cannot be applied to very large boxes, owing to the enorm ous pressure required to effect the squeezing, but each box jolted up is invariably finished by flat ramming on the top, either by hand, or in some cases with pneum atic ram mers. The piston pressure required to produce a reasonable degree of hardness by steady squeezing is evidently much greater than the same energy applied in any form of blow. Machine operators quickly find this out fo r themselves, and most squeezing machines are operated m ore like steam hammers.
Core Blowing
Core blowing, as the name implies, is applicable to cores only or blocks of oil sand used for relatively small moulds, although there is no theoretical reasons why boxes cannot be ram med up in this way if neces
sary. T he use of air under pressure as the carrier for the sand tends to give a very uniform degree of ram ming, free from close packed layers in any par
ticular zone. A lthough some foundrym en are of the opinion that in the act of core blowing, the large grains go to the centre and smaller m aterial to the surface, thus giving an enhanced perm eability in the centre— so much desired in core making practice. All the energy used in the ramming in this case is em ployed in moving the sand only, and thus the power required will com pare very favourably with such
methods as jolting, particularly ram m ing the larger moulds.
Sandslinger
This m ethod of ram m ing resembles the action of throwing a small handful of loam into the m ould, as in loam moulding. The force of the throw is very great, and ram m ing is obtained by the im pact of the sand itself moving at a very high velocity. The mechanism consists of a rotating im peller having only one cup-shaped blade or vane throw ing or delivering sand to the m ould o r core.
The stream of bonded m oulding sand is fed into the path of the cup travelling at a very high speed, where it is caught up in quantities sim ilar to a handful once in each revolution, and expelled from the ram m er head in a downward direction into the m ould. The velocity of this small handful of sand is such that im pact w ith the sand already in the box actually penetrates and packs on, and so builds up a mass of uniform ly ram m ed sand.
This is probably the nearest thing to placing grains of sand in a m ould individually, and should be easily equal to hand ram m ing w hen done properly. The obvious advantages of this m ethod of ram m ing is that all the power is expended on packing the grains, and that the moving parts of the m achine itself are very small. This is particularly noticeable when trying to ram boxes 10 ft. long by jolting, in which case the mass of m aterials lifted on each jolt consists of box parts, table piston, and large mass of sand amounts to, say, 6 to 7 tons. This advantage applies to a lesser extent w ith sm aller boxes.
One im portant advantage of the Sandslinger ram m ing is the aeration which goes on during the process. This has a very beneficial effect on any moulding sand, m ore particularly if the prim ary pre
paration is not w hat it should be. This, in turn, tends to give m uch m ore uniform m ould surfaces and a better perm eability for equal m ould hardness than is the case in moulds m ade by other methods.
F o r example, in jolt-squeeze m achine m aking green sand castings with flat surfaces in the drag, it has been found necessary to avoid jolting drags, otherwise scabs usually result. This m eans that the drags re
ferred to are squeezed only, and are relatively soft on the m ould face. Using the same sand which is largely E rith loam and ram m ing with the Sandslinger, which in turn ram s m uch harder, no trouble is experienced with scabs.
It has been said that the general purposes machine is a myth. This is usually taken as an axiom by well- inform ed founders, and applies w ithout doubt to all machines coming under the previous categories. Most machines are eminently suitable for the type and size of castings or box for which they were designed.
The tru th of this axiom becomes painfully obvious to foundrym en who have a t one time or another tried to dem onstrate to their own satisfaction that there are some exceptions. Thus, the jo lt roll-over machine intended for 30-in. square patterns is not properly em ployed making boxes either bigger or smaller.
O n the one hand, the machine is overloaded, and
JU LY 27, 1944 FOUNDRY TRADE JOURNAL 251 tends to wear out rapidly, while, on the other, the
effort required on the mechanical operation is out of proportion to the results obtained. For example, turn
over boards made to fit 30-in. boxes are both too big and too heavy for any smaller sizes of boxes, and the manual effort has a discouraging effect on time- workers.
The Sandslinger can, however, be called a general- purpose machine, since it will ram moulds or cores within a range practically covering all foundrywork.
It can, of course, w ork in conjunction with any size or type of stripping machine provided there are no high projections which interfere with the travel of the rammer head over the moulding box.
“ Isofirms ”
Fig. 1 illustrates the hardness which results from hand ramming. The spacing of the line indicates the degree of densification. W ith this method of ram ming the variations of this ram ming pattern is theore
tically unlimited, although, of course, it is obvious from everyday experience that good saleable castings can be made from moulds which are well removed from perfectly uniform ramming.
Fi g. 1.— “ Is o f i r m s ” Re s u l t i n g f r o m Ha n d Ra m m i n g.
It is well known that there is a useful range of ramming, and that radical variations from this range are easily detected by placing the finger-tips against the face of the mould— the most elementary and com monest method of judging hardness or degree of ram ming, or it may be better described as a test for soft spots.
Fig. 2 shows a distribution of hardness in moulds or cores ram med by jolting only. In order to obtain the ideal ramming illustrated here, i.e., horizontal straight lines of equal hardness or “ Isofirms ” as they may be called, the moulding sand would have to be introduced into the box evenly, as for example, through a fine riddle in a well-aerated condition, and also by means of a suitable sand fram e to keep a good head of surplus sand above the top of the box itself.
Fig. 3 shows diagrammatically the distribution of ramming density in a m ould made by squeezing in one direction. The depth of the sand, which can be rammed by squeezing is limited, first of all by the total pressure available and also by the surface area of 'the box. F o r instance, as the box becomes nar
rower, the friction on the sides tends to increase, although this factor only appears when the depth is greater than the w idth—a condition which is unlikely to occur in the making of moulds, except when deep patterns are moulded in very small boxes. Thus the pattern is close to the side of the box.
Experimental Data
These theories have a habit of breaking down in practice. Therefore, to check these conclusions, a series of experiments were carried out. A box, 12 in.
square and 9 in. deep, closed top and bottom, was used. F or ramming, the top was removed. It was replaced after ram m ing and the side taken away, so
Fi g. 2 .— “ Is o f i r m s ” f r o m Jo l t i n g.
as to allow hardness testing at regular measured inter
vals from top to bottom of the mass of rammed sand.
Rows of tests were made a t 1-in. interval, that is, commencing 1 in. from the bottom and finishing 1 in.
from the top. The hardness tests were taken by D ietert’s surface hardness tester, measuring indenta
tion hardness in thousandths of an inch and the author’s wire penetration ram ming test. The average of each row of six hardness tests was used to repre
sent the hardness at these levels.
One size of box was used to limit the extent of these experiments, although the size chosen was not equally suitable for all types of ramming, for example,
Fi g. 3,— “ Is o f i r m s ” f r o m Sq u e e z in g.
the Sandslinger does not show at its best because the area presented is sm aller than usual, and the box rams up so fast that the operator has little time for manoeuvring the ram m er head. On the other hand, it is practically ideal for ramming by jolting.
The results illustrated in Fig. 4 show a series of hardness tests, each graph giving the average hard
ness a t varying levels from top to bottom of the box rammed by various means. The heavy black lines indicate the average of each group—thus graph No. 1, the Sandslinger, indicates that the degree of hardness improves slightly towards the top, giving a reasonable uniformly hard" rammed mould.
G raph No. 2 is the average of the group of test
FO U N D R Y TRADE JO U R N A L J U L Y 27, 1944
Sandsl ing er M o u l d i n g Pract i ce
m oulds ram m ed up by jolting only, and this indicates a very rapid falling off in hardness tow ards the top, i.e., from “ hard ” a t the bottom to “ soft ” a t the top.
G rap h N o. 3 is the average of the group o f test m oulds ram m ed by squeezing only, and this indicates a corresponding falling off in hardness from top to bottom , i.e., “ soft ram m ed ” m oulds to “ very so ft,”
a condition w hich is quite useless fo r any form of m oulding. T he p oor show ing o f the squeezing m achine is due to the fact that this box is much deeper than can be handled. If, how ever, the box is refilled and the squeeze o peration repeated, m aking three times in all, the hardness o f the m ould is raised to the hard ram m ed zone, as shown in graph N o. 5.
T he hardness zones m arked out a t the bottom of the graph in Fig. 4 are quoted from D ietert thus:—
. V ery so ft ram m ed m oulds ... 30 Soft ram m ed m oulds ... ... 40 M edium ram m ed m o u l d s ... 50 H ard ram m ed m oulds ... 70 V ery hard ram m ed m oulds ... 85 This point is stressed here because there is som e
times a tendency fo r individual foundrym en to set their ow n interpretation on these figures. S hould there be any tendency to controversy on the point, it is hoped th at the free discussion o f the m em bers will help to clear up the m atter.
Fi g. 4 . Mo u l d Ha r d n e s s a s s h o w n b y: 1, t h e Sa n d s l i n g e r' t b y Jo l t i n g; a n d 3 a n d 5 b y Sq u e e z i n g. No. 4 i s f r o m a n Il l- Ad j u s t e d Sa n d s l i n g e r.
Reference has been m ade, in a P aper* to the Insti
tute in 1933, to the w ire penetration method of m easuring hardness devised by the a u th o r, not as an alternative to the one developed by D ietert, but because no know n m ethod was av ailab le to the author at the tim e. As outlined in a series o f tests carried out to try o u t these m ethods together on the same series o f ram m ed sands, D ie te rt’s m easures a skin hardness because it only penetrates to a distance of a b o u t one sixteenth o f a n inch.
It is som etim es advantageous to be able to measure hardness on a surface o f very lim ited depth, and for this purpose it is em inently suitable, a t the same time it is subject to greater experim ental erro r on that account, but it can be repeated very easily. The wire penetration m ethod m easures ov er the region immedi
ately behind the surface equivalent to the active facing o f a m ould.
T h e graphs in Fig. 5 show this difference in inter
p retation o f the degree o f ram m ing in the experiment ram m ed by jolting. T h ere is evidently a slight loose
ness n ear the sides o f the box an inch below the top surface; this does not rep resen t the average hardness o f the top layer itself.
Special T est
T he foregoing experim ents have dem onstrated that, whereas a sim ple sq u are box o f depth 9 in. cannot be evenly ram m ed by jo ltin g o r squeezing without som e m anipulation, the sam e box was not an adequate test to dem o n strate the abili
ties o f the Sandslinger in this . respect. A box w as therefore designed so as to be particu
larly difficult to ram . There w e re fo u r distinct sections in box, each 9 in.- deep and 6 in. long, but h a v in g breadths 6 in., 4 in., 1 ,in. an d 4 in., as show n in Fig. 6.
A n u m b e r o f experiments w ere carried out by ramming this box w ithout the lower 4-in.
section; the stra ig h t side was then rem oved an d hardness m easured a t reg u lar intervals ov er th e su rfa c e from the top o f th e 6-in. section to the b o tto m o f the 1-in. section.
I t w as intended to carry out a series o f experim ents to show the effect o f flow ability, etc., on the even d istribution and aver
age hardness o b tain ed , and so to m easure the effect of com
m on v ariab les such as grain size, m oisture, a n d b o n d stren g th . H ow ever, after a n u m b er o f such experiments,
* T o u n d rv T ra d e Jo u rn a l, Vol.
X L V III. Pages 171 e t seq., HU e t scq.
