Note: Descriptions are shown in the official language in which they were submitted.
~ 1 ~3 8~
METHOD OF E~EC~RO~LAG ~ELDI~G BY ~A'l'E-TYPE ~LECT~O~ES
~D ~LU~ U~ED I~ 'mE'i~ELDING PROCESS
~IELD ~ T~rE INVENTIO~
~ he inventio~ relates to welding and moIe particularly
~o electroslag welding b~ plate-type electrode~ u~der the
harm~ul i~f`luence of external mag~etic field~ o~ high mag~e-
tic inductio~,
The expre~sion "el~ctroslag welding b~ plate-type
electrodes'~ is used to de~ote electroslag weldi~g method
characterized by the use of electrodes Iormed with plates
of largs cross sectional area~, commensuIable with the gap
between parts being welded.
~ arm~ul i~flue~ces of ex~ernal ma~etic ~ields upon
the welding proces~ maniXest themselves, Xor exampla,
durin~ the in~tallation o~ heavy aluminium bus bars ~or
reduction cells employed at ~on~errous metallurg~ and
chemical indust~y plants where exterllal mag~etic ~ields
are active.
.
. , . . ' ' .
38'~)0
BACKGROUND (:),F THE IN~ENTIoN
To date, the profilem of ~elding in external m~gnetic
fields has not been solved to an~ satisfactory degree. Hand
arc welding by nonconsumable electrodes in an inert atmos-
phere and under a b~anket of flu~ fails to ensure the neces-
sary weld qual~ty, particularly in installation of items,
such as reduction cell bus ~ars, featuring considerable
thickness ~100 to 200mml. Under usual conditions, thiS type
lQ of item can readily be welded together by electroslag we].d-
~ng w~th plate-type electrodes. However, in stron~ external
magnetic fields, the process becomes unstable due to the
fact that ~n electroslag welding a metal is melted by the
heat of-molten slag itsel~ heated by a electric current pass-
ing therethrough (see Slovar-spravochnik po svarke~Welding
Dictionary-Handbook/, "Naukova dumka" Publishers, Kiev,
1974, p.l87~. The external magnetic field acts upon the
melt of slag and metal as a current conductor, imparting it
a motion pulse leading to a loss of stability by the process
manifest~ng ~tself in a sharp misalignment of welding pool
open surface.
It has been experimentally found that satisfactory
welds are obta;nable if welding pool surface deviates from
the horizontal by not more than 15. A greater misalignment
results in a single-sided lack of penetration of edges
being welded and splashing of molten bath.
2 -
' .' - .
~1~38~)~
~ here is known, f`or example, a me-thod for electroslag
welding by a pla-te-type elec-trode (cf.USSR Inventor's Cer-
-tificate No. 149,166) consis-ting in tha-t par-ts being welded
are set a specified dis-tance apart and provided wi-th moul-
ding arrangements composed o* a pocke-t-t~pe pan~ sid~ moulds
and -top discharge planks intended to hold a sla~ ba-th at ~the
final stage of the welding process. A portion o~ weldlng
flux is placed in-to the pocket of the pan, then a plate-type
elec-trode is introduced in-to -the gap be-tween edges of par-ts
being welded and connec-ted to one of the poles of a source o~
welding curren-t, the other pole being connec-ted to par-ts
being welded and the pan. 'rhe welding process is intitiated
by making -the eQd face o~ the electrode con-tact the pocket
bottom, this producing an elec-tric arc which melts th~ p~or-
tion of flux to ~orm a slag bath. Molten s~ag being an elec-
-tric conductor, shunts the arc and so initiates the electro-
slag welding process consisting in -that a welding curre~t
passes through and overheats molten slag.
In turn, -the overheated slag heats in-tensively the
edges of parts being welded and -the electrode, so that the metal
they are made from melts. ~'he molten metal wi-th a bla~ke-t
of molten slag over it forms a welding pool, side areas o-f
which are formed beneath areas of non-fused metal o~ the ed-
ges shaped as steps whose wid-th corresponds to the depth of`
mel-ting (penetra-tion) of the edges. As me-tal mel-ts, -the
level o~ the m~lt in the gap rises -to heat and mel-t new areas
.
,
'. ~
3~
4 --
of edges and of the electrode, -the above steps and the weld-
ing pool as if contlnually moving upwards.
A-t the same time, -the ~e-tal solidi~ies in -the bot-tom part
o~ -~he weldi~g pool producing a welding seam as the welding
pool moves from bo~ttom up. 'rhe weld thus obtained features a
high ~uality owing to homogeneity of weld me-tal and good
welding -thereo~ -to the metal o~ the parts involved.
However, if the a-bove electroslag welding process is
carried out in an external rnagne-tic ~ield, -the result is, due
tO the reasons mentioned, a sh~rp misalignmen~t o~ ~the welding
pool sur~ace (up -to 90 ~rom the horizon-tal), accompanied by
projec-tions o~ the welding pool melt ~rom -the gap. r~hese
phenomena are encouraged by a relatively large open part o~
the welding pool sur~ace, because of which the magnetic ~ield
induced by the welding current is incapable o~ ~eutralizing
-the ac-tion o~ the ex-ternal magnetic ~ield throughout the
open part o~ the melt sur~ace ~nd of preventi~g a vertical
motion o~ the melt on any peripheral area of the sur~ace, -this
resulting in the misalignment o~ the open par-t of the welding
pool surf`ace.
As mean-t here7 the open part o~ the welding pool sur~ace
is the part of the melt sur~ace limi-ted by the projection
of the gap area upon the above sur~ace,
'~he term "gap area" is used here and below to denote
the area limited by the edges of the parts ~eing welded, nu-
merically equal t;o the product o~ the gap width by the edge
wid-th.
, ~ ' ,
' ' .' ;
~ ' ' '
1~38~l~
r~he misalignmen-t of the open part o~ the welding pool
surface incIeases the area wetted by the melt of one o~ the
edges being welded, so redistribu-ting the welding current
between the edges. ~his, in turn, results in a lack o~ pene-
tration on one o~ the edges and a ~ore intensive meltinK o~ the
other edge, so that the step o~ non-melted metal on this edge
acquires a gentl~ sloping shape of'~er:in~ no obstracle ~o the
external magne-tic ~'ield to displace the mel-t previously con-
-tained by the step, with the e~fec-t that the whole o~ the
welding pool sur~ace is misaligned, and the melt, projected
from the gap.
A ~airl~ wide gap, and, in consequ~nce, a large open weld-
ing pool sur~ace area are then necessar~ to preven-t the harm~ul
turbulent processes in the welding pool, as narrowing of the
gap hinders the removal o~ gases evolving actively as a result
o~ the heating o~ the slag-forming ~luæ and causes a satura-
tion of the welding pool metal with gases.
The term "slag-~orming fluxl' is used here and below to
denote a welding ~lux which is melted to create a slag bath.
Intensive evolution o~ gas `~uring welding process is due
to that the currently employed ~luxes boil readily under the
e~fect o~ welding temperature and give o~ volatile compounds.
This type o~ fluxes includes, for example, a ~lux ~'or welding
aluminium according to the U.~.~.R. Inventorls Certi~icate
No. 279,3119 containing in per cent by weight:
lithium fluoride 20 to 22
3E~
sodium fluoride 28 -to 30
po-tassium f`luoride 15 to 20
sodium chloride 30 to 35
SU~AL~Y ~F THE INVEN~ION
I-t is thereo~re an objec-t of the inven~ion to provide a
method for electroslag welding by a pla~te--type electrode
and a welding flux ensuring -the stability of the welding pro-
cess in external magnetic ~ields -through op-timization of the
dimensions o~ the open par-t of -the welding pool surface.
Another object o~ the presen-t invention is -to raise the
boiling point of the flux.
The above and other objects o~ ~the invention are attained
in a method for electroslag welding by a plate-type electrode,
comprising providing a gap be-tween edges of parts being wel-
ded, in-troducing a plate-type elec-trode into the g~p and mel-
ting the electrode and the edges by -the heat of an electri-
cally heated slag to create an upward-moving welding pool,
side areas of the surface thereof being formed, as -the edges
melt~ underneath moving steps of non-m~lted me-tal, according
to -the ~nvention~ parts to be welded are brought toge-ther to
form a gap, the sur-~ace area "B" thereof being in a ratio
to the area "A" of the horizontal cross sec-tion of -the elec-
trode and to the area ~a~ 0~ the projection o~ the surface
of -the welding pool upon a horizontal surface of A : B : C =
.
1 ~ ~ 38~ ~
= 1 (1.2 to 1.5 : (2.5 -to 4.5) in order -to keep the misa-
lign~nt o~ the ~el~ing pool surface within 15 with the aid
of the moving steps~ which limit -the vertical motion o~ the
side areas of the welding pool sur~ace~ equal in area -to
between 40 and 75 per cent of the area thereo~, and o~ the mag-
netic ~ield o~ the elec-trode.
'rhe above method for elec-troslag welding by a plate~-type
elec-trode ~ea-tures s-tability o~ -the process in ex-ternal mag-
netiG ~ields through -tha-t, for a given ratio o~` the sur~ace
areas A, B, C, the open part o~ the welding pool sur~ace has
such dimensions that -the magnetic field of` the plate--type ele-
c-trode neutralizes -the action OL stron~ external ma~netic ~ield~
and prevents splashing o~ the melt. ~dditionally~ the moving
steps ha~e su~icient dimensions and a ~avourable shape for
containing the side areas of the welding pool sur~ace no-twith
standing the action of the external magnetic fields.
It is good practice to impart the moving steps a speci-
-~ied shape by applying upon the edges of parts being welded
an electric insulating ma-terial having a brea~down tempera-ture
~ rll aDove the melting point "~m" of the metal of the parts
being welded by a f`ac~or o~ 1.1 to 1.5.
Placi~g the moving steps in a speci~ied position; ~or exam-
ple, close to a hori~ontal one7 enhances their capability of
preventing -the misalignment o~ the side areas of the welding
pool sur~ace under the ac-tion of external magnetic ~ields~
The moving s-teps acquire a speci~ied shape because -the
~1~38~(1
insulatlng material restric-ts the we-tting of the unmelted
metal by the melt, and, therQ~ore~ the intensity of -the
thermal action, -to predeterm:ined areas. If ~br~l~ m, -the
electric insulating material will break down below the surface
of -the slag ba-th, and so no speci~ied shape of steps will be
obtained. If ~br> 1.5 ~m' ~he insulating material will
not have enough time to break down completely be~ore it comes
into contact with the me-tallic ba-th, -this resulting in slag
inclusions in -the weld.
~ he electric insula-ting material should pre~erably con-
tain a non-organic compound - sal-~ - and/or mixture of salts
of ~a, Na, K, Mg, Ca~ Zn, B, Al and /or their oxides and/or
their carbides, as these compounds poss~ss the necessary ther-
mal chara~teristic~.
It is also suggested -that the electric insulating ma-
terial contain an organic compound, such as cellulose, ve-
neer, organic resin, as this type of materials possess the
necessary thermal charadteristics and, additionally~ can rea-
dily be secured to the surface of edges of parts to be wel-
ded.
~ he above and other objects are attained also by providing
a flux for electrosla~ welding, comprising lithium fluoride
and sodium fluoride, and according to the inven-tion9 additi~
onally containing potassium fluoride a~d calcium fluoride in
the f`ollowing proportions, per cent by weight:
~38~
lithium :Eluoride 60.0 to 90.0
sodium ~luoride 5.0 to 20.0
calcium ~luoride 1.0 -to 5~0
potassium ~luo.ride 4.~ -to 15~0
'l'he above flux has a boiling point higher than the wo.r-
king electroslag welding temperature, ~his sharply reduci.ng
gas e~olution during weldi.ng, requiring no large ~ap between
the edges of par-ts belng welded ~or removal of the gases and
making i-t possible -to decrease the sur~ace area of the open
part of -the sur~ace of welding pool~ so as to, as men-tioned,
stabilize -the welding process where carried out in an ext~rnal
magnetic field.
It is also advantageous to provide a calcium fluoride to
sodium fluoride ratio of l-to-5~ -the proportions of all the
components being as follows7 per cent by weight:
li-thium fluoride 6000 ~o ~0.0
sodium fluoride 5.0 to 20.0
calcium fluoride 1.0 to 4.0
potassium ~luoride 4~0 to 15.0
~he above calcium fluoride to sodium fluoride ra-tio achi-
eves a maximum activity of -the -flux with respec-t to a metal
being welded.
BRIEF D~S~RIPTION 0~ ~EE DRAWINGS
~ hese and other objec-ts and fea-tures o~ -the inven-tion
become readily apparent from one embodiment thereof which
:
3~3QO
~ lo --
will now be d~scribed b~ wa~ of example with re:~erence to
the accompanying drawing~ 7 ln which:
Fig l is a schema-tic longi-tudinal ver-tical sec-tion of a
general welding setup with moulding arrangements f`or assemb-
ling parts to be welded and carrying ou-t the electroslag
welding method, according to the invention;
~ ig.2 is a schematic longi-tudinal ver-tical section o~` a
se-tup with moulding arrangements ~or par-ts -to be welded whose
edges are half covered with an insulating material;
Fig.3 is a schema-tic horizontal section of a setup, in-
cluding moulding arrangements, Yor assembling parts to be
welded with selectively coated sur~aces o~ edges;
Fig.4 is a schematic horizontal section o~ a setup with
moulding arrangemen-ts ~or a heavy single-piece part and an
assembled packe-t o~ parts;
Fig.5 is a scheamtic longitudinal vertical section o~ a
setup, inclu~ing moulding arrangements, ~or parts to be wel-
ded with alternative coating o~ edges ~or welding elements
of various heat removal capacities.
DESCRIPrIION OF r~HE ~REFER~ED EMBODI~E~'~
The me-thod ~or electroslag welding is carried out in
an active magne~ic Yield having a magne-tic induction o~ up
to 40 or 45-10-3 '~0
'~he edges of parts 1 and 2 (see ~ig.l) to be welded,
~or example, ~us bars~ are coated with an electric inaulating
313~(~
ma-terial 3 having a breakdown tempera-ture ~br by a ~'actor of
1.1 to 1.5 higher -~han the meltin~ point ~m of -the parts,
no-t less than 5G% of the sur~ace area of the edges being
coated and -the parts being posi-t:ionecl so as to provide a gap
between -the edges~
~ he moulding arrangemen-ts consistlng of a pan 4 having a
pocket ~, side moulds 6 and top discharge pl.anks 7 are mounted
nex~ on the parts 1 and 2~ A portion of a slag-~orming ~lux
is charge~ into the pocket 5, the composition of the Ilux
being as ~ollows, per cent by weight:
lithium fluoride 60.0 -to 90.0
sodium fluoride 5.0 -to 20.0
calcium fluoride 1.0 -to 5.0
po-tassium fluoride ~ to 15.0
A pla-te-type electrode 8 con~ected -to one of the poles
of a welding current source (omi-tted on -the drawings) is
i~troduced into -the gap t the other pole of -the welding cur-
rent source being connected to the parts to be welded 1 and
2 and the pan 4.
~ he parts 1 and 2 are brought -together so as to form -the
gap Y~hose surface area 77B7~ iS in a ratio to -the sur~ace area
"A" of the horizontal cross section of the electrode of
A : B - 1 , (1.2 to 1.5).
~ he welding process is s-tarted by bringing the end ~ace
of the electrode 8 in-to contact wi-th the bo-t-tom of the pocket
5, this initiating an elec-tric arc which mel-ts the abo~e por-
~1~3~300
-- 12 --
tion o~ ~lux to produce a bath 9 of molten slag. '~he mol-ten
slag shwnt~ -the arc, and so startc;-the elec-tIoSlag welding pro-
cess. A welding current passes through and overhea-ts -the
molten slag, -the heat ~hereof causing, in the areas where the slag
comes in-to direct con-tac-t with the me-tal of the electrode
and o~ the edges o~ the parts to be welded~ an int~nsive mel-
ting of the me-tal which flows in-to -the pocket 5. The mol-ten
me-tal -together with the bath 9 of mol-ten slag covering i-t .Eorms
a welding pool 10 ~vhose side areas are formed beneath areas
of non-melted metal of the edges having the shape of moving
steps 11 and ~3 whose width corresponds -to -the depth o~ pe-
netration of the edges. ~he depth of -the penetra-tion is such
that .;~he area "A" and -the horizontal cross sectional area
of the electrode are in a ratio to the area "Cl' of the pro-
jec-tion of -the surface of the welding pool upon a horizontal
plane of 1 : (2.5 to ~.5) 'l'his is achieved by adjusting the
parameters of the welding process Iw and Unl~ which are
respectively the in-tensity of -the welding current and the
no-load voltage of the weldi~g current source.
As the edges o~ the par-ts 1 and ~ are coa-ted with an
electric insula-ting material 3, the moving steps 11 and 12
are in a posi-tion close to -the horizo.ntal, as the area o~ the
intensive ther~al action of the slag bath ~ upon the metal
o~ the parts 1 a:nd 2 is limited to -tha-t of direct contac-G.
'1'he ex~ernal magne-tic ~ield acts upon the welding pool 10
as upon a current conductor, impar~ing a mo-tion pulse there~o.
.
~l143~0~13
-- 13 --
However, since the proce~s is car:ried out a^t the specified
ratio of -the surface areas A, B, C, the open part of` the
surYace of the welding pool 10 has such a size -that the
magne-tic field of the plate--1-ype electrode 8 neutralizes
-the action o~ -the external magnet:ic field, whereas
the moving steps 11 and 12 have suf~icient dimension~ and
e
a shape adquate for restricting the displacement o~ -the side
areas of -the welding pool surface. ~hi.s enables the misalign-
ment of the welding pool -to be kep-t withln the range of 0 to
15 from the horizontal and the effec-t of the ex-ternal
magnetic ~ield -to be neutralized. ~he welding process acquires
stabili-ty with the ef-~ect that -the weldi..ng pool rises withou-t
misalignment up -the gap-as the metal of the edges and of -the
electrode melts and the steps 11 and 12 move upwards. At the
same -time, -the metal solidi~ies in -the bottom part o~ the
welding pool to form a weld..
The invention will now be described by the following
illustrative E~amples.
Example 1.
~ luminium bus bars 1 and 2,140 mm thick, are electro-
slag-welded in a magnetic field o~ a magnetic induction of
40-10 3 ~. Edges to be welded of bus bars ha~e bee~ coa-ted
in advance with an electric insulating material 3 based on
~aCl whose breakdown temperature is ~br=800 to 900C, i.e~
b~ a factor of 1~2 to 1.3 higher -than -the melting poi.n-t
~m ~ 660C of aluminium~ A welding pla-te-type electrode 8
.
3~0
Irom aluminium was 20 mm -thick. ~le process was stabllized
by providing a ra-tio of A : B : a = 1 : 1 . 2 : 2.5, the wid-th
of the gap be-tween the welding edges and the depth of pene_
tra-tion of -the welding edges having been accordingly calcula-
ted equal ~o respec-tively ~4 and :L3 mm.
In accordance with -the calculations, ~he bus bars 1 and
2 were brough-k together -to provide a gap between the edges o-
~24 mm.
Moulding arrangements consisting a pan 4 with a pocke-t 5,
side moulds 6 and -top discharge planks 7 were assem'bled on
~he bus bars 1 and 2D
As the boiling poin-t ~bsl ~ -the slag-~or~ning~ I'lux had
to be greater than the welding tempera-ture of the aluminium
bus bars TW=1200 to 1400C, the ~lux had -the composition 'below,
% by weight:
lithium ~luoride 60.0
sodium -~luoride 20 ~ 0
calcium fluoride 5.0
potassium ~'luoride 15.0
the boiling point being ~-b=1500C.
~ portion o~ slag~~orming f'lux was charged into ~he po-
cke-t 5. ~ plate--type electrode 8 was then in-kroduced into
the gap, and an elec-troslag welcling process was initia-ted.
A required depth of penetra-tion was achieved by conducting
the process under ~he conditions below:
w = 7~ kA
~nl = 44 V
~1~313()0
~ he resul-ting moving s-teps 11 and 12 had R posltion close
to the horizontal, and the misalignment of -the sur~`ace o~
-the welding pool was not more tha~ 15C
~he effec-t of this procedure was a quali-ty bus bar weld
50 mm wide.
Example 2
Ingots of an alloy based on aluminium and containing 5-8~o
magnesium, 140 mm thick, were electroslag-l.velded in a magne-tic
field o~ a magnetic induc-tion o~ 40-10 3 ~
~he mel-ting poin-t o~ the alloy was '~m-654C. Edges were
insulated electrical]~ with a coat of Na3AlF6 having a break-
do~ point of '~br=1000C
~he plate-type electrode was 20 mm -thick.
~he ratio of the areas was A : B : C = 1 : 2.3 : 3.5.
Gap width was 26 mm.
~dge penetra-tion dep-th was 22 mm.
Welding conditions :
~ Iw = 9~5 kA
Unl = ~2 V
~he welding temperature: ~W=1200 to 1400C.
~he ~lux had the chemical compo3ition below, % by wei~h-t:
lithium fluoride 90.0
sodium fluoride 5.0
calcium fluoride 170
potassium fluoride 4~0
.
: . . , ~ -
'
38VO
-- 16 --
The boiling poin-t o~ -the flu~ was r~b=1510C.
The moulcling arrangements were assembled, anrl the elec-
troslag welding process, ini-tia-ted~ as in -the EXA~E 1. '~he
mi~alignment of -the surface of the welding pool was no-t greater
than 15 ~rom -the horizontal. 'l'he resul-t of the above proce-
dure was a quality weld, 70 mm wide.
Example 3
B ~e
~ orgings ~sx elec-troslag-welded in a magne-tic field o~ a
magne-tic induc-tion of 40010 3~.
~ he material o~ the ~orgings and of the electrode was
an iron alloy containing, ~0 : C, 0.10; Si, 0~54; ~n5 1.10;
Cr, 17.75; ~i, 9.3; ~i, 0.51; ~e, the balance to 100.
Tm = 1385C-
Ingot thickness was ~00 mm.
The coat material was a mixture o~ MgSo4 and A1~03 taken
in a ratio of l-to-l.
~ br=1530 C.
'~he coat was applied over 50 % o~ the area o~ edges,
in their -top part (see ~igo2)~ 'L'his led to a more intensive
initial stage of ~he weldi~g process with -the position o~
the stops being kept close to the horizontal.
~ he plate-t~pe electrode was 12 mm thick.
'L'he ratio of the areas was A : ~ : C = 1 . 1.5 : 4.5 .
Gap width was 18 mm.
Edge penetratio~ depth was 18 mm~
Welding condi-tions:
' ~ "' . '
.
386~(~
17
Iw = 6 kA
Unl = 38 V
'rhe welding temperature was TW=1540C~
r~he flux employed had -the ~ollowing compc3ition~ ~0 by
weight:
lithium ~luoride 70.0
sodium ~luoride 20.0
calcium ~luoride 4.0
potassium ~luoride 6.0
~b = 1520C.
~ he moulding arrangements were assembled, and the elec-
troslag welding process, in-titiated, as in the EXAMP~E 1.
Welding pool surface misalignment was not greater than
15 from.the horizontal.
~ he procedure resulted in a quali-ty ~orging weld, 54 mm
thick.
~xample 4
Forgings were electroslag-welded in a magnetic ~ield
o~ a magnetic induction of 40-10 3 ~
The material o~ tke ~orgings a~d o~ the electrode was an
iron-nickel based alloy con~taining~ %: C, 0.04; Si, 0.51;
Ni, 0.27; Cr, 19,60; Ni, 27.~0; B, 4.78; Mn~ 2.90; Nb~ 1.05
~e, the balance to 100.
~ m = 1~20C.
Ingot t~ick~ess was 100 mrn.
~43800
~ 18 -
'~he material o~ the coat was a mix-ture of Na203, K207
Li20, CaO -taken in a ra-tio of 1 : 1.1 lo
'~br = lL~0C.
IrO economize ~he ma-terial, the coa-t was applied onto the
boundaries o~ the edges -to be welded (see Fig,3~ so as to
cover 50% of the sur~ace area -thereo~ `he moving steps
remained prac-tically horizon-tal during welding.
~he plate-type elec-trode was 10 mm thick.
~he ratio of the areas was A : B : C = 1 : 1.3 : 3~5.
rlhe gap wi~-th was 13 mm.
'~he edge penetration depth was 11 mm;
The welding conditions were as follows:
Iw = 2.0 kA
Unl = 36 V
~rhe welding temperature was TW_1500C.
'~he composi-tion of the flux, % by weight:
lithium ~luoride 85.0
sodium fluoride 4.0
calcium fluoride L~ . o
potassium fluo~ide 7.0
Tb = lslsa.
r~he moulding arrangements were assembled~ and -the
electroslag-welded, initiated, the same as in -the ~XAMPIE 1.
rl`he misalignment of the welding pool ~ur~ace was not greater
than 15 from the horizon~al. '~he procedure yielded a
~uality weld o~ -the ~orgings, 35 mm wide.
.
~3~30
- 19 -
Example 5
Bus bars were electroslRg-welded in a magnetic
-~ield o~ a magnetic induc-tion o~ 40 10 3 '~.
Ma-terial of -the bus bars and -Ghe electrode was copper.
~m = 1080C.
bus bar thick~ess was lO~ mm~
A l1~he ma-terlal o~ the coat was based on
-
' q! = lL~20C.
The plate-type electrode was 20 mm -thick
~he ratio o~ the areas was A : B : a ~ . 5 : 4.5.
~he gap wid-th was 3G mm.
11he edge penetration depth was 30 mm.
Welding conditions:
Iw = lO kA
Unl = 44 kA
~w = 1450~
~lux composition, ~0 by weight:
lithium ~luoride 90 0
sodium ~luoride 5.0
calcium fluoride l.0
potassium ~luoride 4~0
Tb=1505C.
The moulding arra~gemen-ts were assembled, and the
electroslag welding process, initiated, the same as in -the
:E5X ~PIæ 1 .
. ~' ''`''' '- ' .
. ~
1143800
~ 20 --
~ he misalignmen-t of the welding pool sur~ace was not
greater -than 15 from the horizontal.
r~he pro~edure yieldecl a qualit~ ingot weld 90 mm -thick.
E~ample 6
Aluminium bus bars were electroslag welded in a magne~ic
field. 'rhe bus bar 1 was formed with an ingo-t, and the bus
~ar 2, wi-th a package of sheets (see ~ig.4), ~he magne-tic in-
duction of the field was L~O- 10 3 ~,
~ he bus bars were 140 mm -thick.
'~m = 660C.
~ he material of the coat a veneer shee-t 2 mm thick.
~ br = 730-750C.
The edge of the bus bar 2 was covered completely, and the
edge of the bus bar 17 from the top -to half -their width (see
~ .5), this to allow for the differen-t hea~ removal proper-
ties of the bus bars 1 and 2.
~ he pla-te-type electrode was 20 mm thick.
~ he ratio of the areas was A:B:C - 1 : 1.2 : 2.5.
~ he gap width was 24 mm.
~ he ed~e penetra-tio~ depth was 13 mm.
Welding conditions:
Iw = 7- kA
U~
~w = 1200C.
The composition of the flux was as follows 3 % by weight:
,'
ll1~380(~
- 21 -
lithium ~luoride 75.0
sodium ~luoride 15.0
calcium ~luoride 3.0 -
potas~ium ~luoride 7.0
tb = 1500C.
~he mouldi~g arran~emen~s were assembled, and the electro-
slag welding process 3 intitiated, -the same as i~ -the ~XA~PIæ
1.
'l`he procedure yielded a quality weld 50 mm thick.
Example ~
I-tems were welded in a magnetic ~ield o~ a magnetic
induction of 40-10 3 '~'.
: 'I'he material o~ the ~orgings and o~ -the elec-trode was an
iron-based allo~ containing, % : C, 0.10; Si~ 0.54; Mn, 1.10;
Cr, 17,75; Mi, 9~3; ~i~ 0~51; ~e, ~he bal~nce.
'~m = 1385C.
: ~hickness o~ the ~`orgings was 140 mm.
~he material o~ the coat was rosin with a CaO ~iller.
=1530 C.
~he b,--ickness of the plate-type electrode was 12 mm.
~: ~he r~tio of ~he areas was A: B: C - 1: 1.5: 405,
.: The width o:~ the gap was 18 mm.
:~ ~he depbh o~ pene-tratio~ of the ed~es was 18 mm.
;~ Welding conditions :
w = 6 kA
U~l = 3
. .: ~ . . - . . . - :
.: - : - :
:"
: ; ~ ~ . . .
1143800
- 22 _
~w = 15~0~.
~he composition o~ -the ~lux was as ~ollows~ % ~y wei~ht.
li~hium ~luoride 6~.0
sodium ~luoride 20.0
calcium ~luoride 5.0
potassium fluoride 10.0
~b= 1550C.
The moulding arrangements were assembledg and the electro-
slag welding process, ini-tiated, as in the EXAMP1E 1. ~he mi-
salignment o~ -the welding pool was no-t greater than 15 ~rom
the horizontal.
'~he above procedure yielded a quali-t~ weld o~ -the
forgings, 54 mm wide.
Example 8
~he ~orgings were electroslag-welded in a magnetic field
of a magnetic induc-tion of 40-10 3'~.
'~he material o~ the forglngs and o~ the electrode was an
aluminium-based allo~ containing 5.8 % magnesium.
'~m = ~54C.
'~he thickness o~ the ingots was 140 mm~
'~he material of the coat was based on cellulose.
~br = 730C.
'~he thickness of the plate-type electrode was 20 mm.
~he ratio o~ the areas was A : B : C = 1 : 1.3 : 3.5.
~he width of the gap was 26 mm.
:
~1~380
23 _
~he depth of -the penetration of the edges was 22 mm.
Welding conditions were as follows:
Iw = 9 5 kA
Unl = 42 V
The co~o~l~io~ ~ the ~lux was as foIlows, % by weight:
lithium ~luoride 75.0
sodium fluoride 15.0
calcium fluoride 3.0
potassium ~`luoride 7.0
rrb = 1490~-
'~h~ moulding arrangeme~ts were assembled, and the electro-
~lag welding process, initiated, as in the ~XAMP~E 1. r~he
misalignment of the surface o~ -the welding pool was not
greater than 15 ~rom ~he horiæon-tal.
~he procedure yielded a quality weld o~ the forgi~gs
70 mm wide.
E~ample 9
Ingots were electroslag-welded in a magnetic Yiedl of a
magnetic induction o~ 40-10 3 '~.
he material of thé ~orgings and of the electrode was
~ an iron-and-nickel-~ased alloy containing, ~0 : C~ 0~04;
; Si, 0.51; Mn, 0.27; Cr, 19.6 ; ~i, 27.8; B, 4~78; Mo, 2.9;
Nb~ 1.05; Fe, the balance.
r~m = 1320C.
he~thickness of the ingots wa~ 100 mm.
~` 'rhe ma-terial of the coat was laminated ins~latio~.
.
-.................... , ~
~,
11~38~0
-- 24 --
'~br = 1460C.
~he -thickness o~ ~he plate-t~pe electrode was 10 mm~
~he ratio of the areas was A : B : G _ 1 : 1.3 : 3.5.
The width of the gap was 13 mm~
~l~he aepth o~ pene~ration of ~he e~g~s was 11 mm.
Welding conditions:
Iw = 2.0 kA
U = 36 ~,
nl
= 1500C.
~he composition o~ the flux was as follows, ~0 by weight:
lithium fluoride 75.0
sodium ~luoride 15.0
calcium fluoride 3.0
potassium fluoride 7.0
Tb= 1510C.
The moulding arrangements were assembled, and the electro~
slag welding process, lnitiated, the same as i~ the EXAMPI~ 1.
~he misaligment of -the welding pool surface was not greater
than 15 from the horizontal.
~he procedure yielded a qualit~ weld o~ the ~orgings,
~ 35 mm wide.
:~ :
Example 10
Bus bars were elec-troslag-welded in a mag~etic -~ield.
The magne-tio induotion of the field was 40-10 3 ~.
; ~he material o~ -the ingots (bus bars) and of the electrode
was copper.
; ~:
'':
:: : ~ . .
3800
~m = 1080C.
'~hickness of -the i~gots was lO0 mm.
~he material of the coat was te~olit,
'~br ~ 1420C.
~he thickness of the plate-t~pe elec-trode was 20 mm~
'~he ratio of the areas A : B : C = l : 1.5 : ~,5.
'~he wid-th of the gap was 30 mm.
'~he dep-th of the pene~ration o~ the edges was 30 mm.
Welding condltions:
Iw = lO kA
Unl = 44 ~.
r~ = 1450C.
. .
The co~po~ition o~ the ~lux was as follows, ~0 b~ weight:
lithium ~luoride 80.0
sodium ~`luoride lO~0
calcium fl~oride 2.0
potassium ~luoride 8~0
~b = 1505 C.
~he moulding arrangements were assembled~ and -the
elsctroslag welding process, initiated, the same as in the
EXAMP1E 1. '~he misalignment of the weldi~g pool surface
~ was not grea-ter than 15 ~rom the horizontal~
`~; rL'he procedure yielded a qualit~ weld o~ the ingots,
90 mm wide.
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