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APPLYING NEW BLOW-FORMING PROCESSES TO OBTAIN NEW
STRUCTURAL COMPONENTS FOR AUTOMOTIVE INDUSTRY: A-
PILLAR
Víc o Oli e as Mé ida, Ph.D. (p)
Xa ie Agus i Ripoll.
SEAT Technical Cen e .
Ma kus Fe s l
SEAT Technical Body
Abel Zahinos Ruiz
Vic o Clua
SEAT-UPC Chai S uden
Abs ac
The aim o his p ojec is o de e mine he echnical iabili y o he bodywo k manu ac u ing p ocess using
he blow- o ming echnology. Speci ically, he blow- o ming echnology has been s udied o be applied o
manu ac u e he A-pilla . The esul s o using his echnology e eal he ollowing:
- Weigh and CO2 educ ion due o he ac ha his echnology makes i possible o use hinne
high s eng h s eel.
- Passenge s‘ sa e y imp o emen .
- Imp o emen o he d i e ‘s sigh angle as a esul o he smalle sec ion o he A-pilla .
- Reduc ion o manu ac u ing cos s.
- Reduc ion o he numbe o componen s o he A-pilla .
Du ing he de elopmen s age, he ollowing esul s a e also achie ed:
- Ha den ma e ial abo e 1.500 MPa.
- Up o 20% o A-pilla weigh educ ion.
- U iliza ion o ma e ial by 95% s 40% o cu en use.
- Componen numbe educ ion.
Resul s sugges ha he applica ion o he blow- o ming echnology o manu ac u e he A-pilla is
echnically iable and complies wi h he geome ic and manu ac u ing equi emen s.
Key wo ds: Blow- o ming; Manu ac u ing p ocesses; High s eng h s eel; A-pilla .
1. In oduc ion
La ely, he au omo i e indus y sec o is expe iencing a p og essi e ha shening o demands new models
mus mee . A clea example o his ac is he obliga ion o o e ehicles which p o ide g ea e sa e y o
i s occupan s a c ash es s. O he impo an demand is he con inuous educ ion o ehicle consump ion,
and in o de o achie e i , he s a egies au omobile p oduce s use include cons an educ ion o di e en
componen s and pa s weigh . In o de o mee hese demands, which occasionally could seem
con adic o y, p oduce s a e looking o al e na i es o ma e ials adi ionally used o design and
manu ac u e s uc u al componen s. An example o his ype o ma e ials a e ad anced high-s eng h
s eel, which allow o no ably educe he hickness o he pa s, compa ed o pa s designed wi h o he
ypes o s eel, and, he e o e, weigh in pa s wi h s uc u al equi emen s in he bodywo k.
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Howe e , he use o hese ypes o s eel en ails se ious di icul ies. Fi s , when using high-s eng h s eel
in adi ional molding p ocesses, such as cold o ming, se ious p oblems a ise. These p oblems, which
a e no o igina ed om he e y s eel‘s lack o duc ili y, a e due o he magni ica ion o he elas ic eco e y
phenomenon, and o he p onounced wea ing and cons an b eakages o he o ming ools, which obliges
o econside and edesign he ma e ial he o ma ion equipmen a e made o .
These p oblems a e pa icula ly ele an in high-s eng h s eel, highe o 1000 MPa, p ecisely hose which
mos in e es awake in indus y o he ele an weigh dec ease i s use would mean.
Wi h he objec i e o sol ing hese p oblems, in he pas ew yea s, new o ming p ocesses o s eels wi h
up o 1500 MPa o mechanical s eng h a e being de eloped. Ca ied ou in ho , so ha he s eel pla e
de o ms due o he high empe a u e, hese p ocesses seek o exploi he cha ac e is ics o he ma e ial in
i s aus eni e phase, in which he ma e ial has a high duc ili y. A e he ho me al o ming, i is empe ed o
achie e ma ensi ic s uc u es. The empe ing has he peculia i y o being ca ied ou wi hin he o ming
equipmen , whe e i akes ad an age o he low empe a u e o he ool, which makes he subsequen
cooling, which also se es as sel - empe ing, emo e he p oblem o elas ic eco e y. This p ocess, called
ho s amping, which as s a ed abo e, allows wo king wi h high s eng h s eels, is used by SEAT o
manu ac u e A and B pilla s o he new SEAT Ibiza.
This a icle shows he esul s ob ained om he esea ch ca ied ou o he design and de elopmen o
he A-pilla , using high-s eng h s eels and applying new manu ac u ing echniques. The esea ch ca ied
ou has enabled assessing he use o hese new echnologies o he de elopmen o s uc u al elemen s
by ho blow- o ming. The da a ob ained a e o g ea use o he compa ison o hese echnologies wi h
hose adi ionally used, and acili a es decision-making p ocess in ela ion o he possible use o high
s eng h s eels and ho me al o ming in u u e de elopmen p ojec s o ehicles o he b and.
2. P ojec Objec i e
This a icle desc ibes he esul s o one o he p ojec s SEAT has ca ied ou , aimed o educe ai
con aminan emissions om he use o i s ehicles, as di e en Eu opean and au omo i e sec o ‘s
en i onmen al egula ions demand. One o he possible cou ses o ac ion o achie e i is he educ ion o
he o al weigh o he ehicles by he eplacemen o hea ie by ligh e componen s, wi hou ad e sely
a ec ing he pe o mance o he ehicle.
This a icle p esen s he esul s o he p ojec which aims o s udy he easibili y o implemen ing new
o ming p ocesses, speci ically he so-called ho blow- o ming, o he design and manu ac u e o one o
he s uc u al elemen s o he ehicle: he A-pilla o SEAT Leon's u u e model. In addi ion o de e mine
he echnical iabili y o he p ocess, he p ojec is aimed o s udy he cha ac e is ics o he mos
app op ia e ma e ial o he pa 's design and o he e y p ocess used o i s p oduc ion.
I easible, his new o m o ho me al o ming would allow SEAT Technical Cen e (he ea e , CTS) apply
his echnology in o he pa s o he ehicle, o g ea e dimensions, such as he ing, which would help o
achie e educ ions in weigh and la ge emissions.
The speci ic objec i es o he p ojec a e:
- Redesigning he A-pilla , so ha i can adap o he geome ies o be ob ained by he how blow-
o ming p ocess.
- Selec ing he ma e ials o be used o make he piece by his p ocedu e, while main aining
minimum equi emen s a 1500 MPa.
- Analyzing he p ocess o manu ac u ing as a whole, de ec ing po en ial poin s o imp o e and
possible edesign o he piece.
- Analyzing he eques ed pe o mances: mechanical and esis ance o co osion, among o he s.
3. Jus i ica ion and Expec ed Bene i s
The expec ed bene i s, in case he easibili y o he p ocess is demons a ed, a e lis ed below:
- Weigh educ ion and, consequen ly, o CO2 emissions o ehicles.
- Inc ease in passenge sa e y.
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- Reduc ion in manu ac u ing cos s and an imp o emen o he p oduc ion p ocess's impac on he
en i onmen .
The idea behind he use o his ype o me al o ming by ho blowing is he possibili y o using high
s eng h s eels, which allows ob aining pa s wi h high mechanical pe o mance using a minimum o
ma e ial. This implies ha , in case his ype o p ocesses and ma e ials can be used, i could ansla e in
he educ ion o bo h he sec ion o he pa and i s weigh . O he ad an ages ha migh be achie ed,
esul ing om weigh educ ion on he pa unde esea ch, a e a educ ion in CO2 emissions and an
imp o emen in he ehicle dynamics, in he accele a ion as well as in he b aking, and i s beha io on he
oad. This is due o he ac ha weigh educ ion in he ehicle's uppe a ea, place whe e he pa unde
s udy is ound, con ibu es o shi he cen e o g a i y o he ehicle owa ds he g ound.
On he o he hand, he use o mo e esis an s uc u al componen s would p o ide g ea e sa e y o he
passenge s o ehicles hanks o:
- Inc ease o he esis ance o he elemen s men ioned abo e, helping o s eng hen he esis ance
o he en i e ehicle.
- Inc ease o he d i e 's ield o ision, since i is possible o p oduce A-pilla s wi h a smalle c oss-
sec ion, meaning he leas possible hind ance o he ield o ision. This would educe he blind
spo s o igina ed in his a ea and would inc ease sa e y while d i ing.
Finally, i is expec ed ha he use o a amoun o manu ac u ed by ho blow- o ming will help b ing abou
a educ ion in he complexi y o he manu ac u ing p ocess o he ehicles, and he e o e a educ ion in
bo h he manu ac u ing cos s and he impac o he p oduc ion p ocess on he en i onmen . This would be
e lec ed h ough:
- The educ ion o he numbe o componen s ha a e pa o he A-pilla , hus ge ing logis ical
ad an ages, a educ ion in manu ac u ing and handling spending, he use o ewe ools, a
cheape manu ac u e and he minimisa ion o assembly expendi u e.
- The inc ease o he deg ee o be e use o s a ing ma e ial, due o he possibili y o mo ing om
he cu en s amping p ocess o a u u e one o shaping.
In summa y, he implemen a ion o his p ojec is expec ed o educe he weigh o he A-pilla in
app oxima ely 35 pe cen and educe cos s and in es men while main aining o e en imp o ing he
s uc u al beha io o he pa .
4. Me odology and ac i i ies
4.1. An eceden s
This sec ion explains he backg ound and mo i a ions ha led o he app oach o he use o new ma e ials
and p oduc ion p ocesses o design and manu ac u e he ehicle's s uc u al elemen s, as he A-pilla is.
Wi hin he body o a ca he e a e a se ies o high-s uc u al esponsibili y componen s, such as he pilla s
A, B, C and he sill boa d, which o m he so-called ing.
Du ing he de elopmen o p e ious p ojec s, and mainly in hose ela ed o he de elopmen o he
cu en SEAT Ibiza, some decisions we e aken such as he elimina ion o he oo 's cen al beam, wi h
he basic goal o educing weigh , while ensu ing he p o ec ion o he occupan s in he e en o a
collision. This con ibu ed he ollowing bene i s: educing he complexi y o p oduc ion, educ ion on he
numbe o pa s and less logis ical cos s. By elimina ing he new Ibiza's main beam, some measu es we e
aken o gua an ee he p ope unc ioning o he ehicle. Howe e , he ma gins o sa e y ega ding he
side-impac we e signi ican ly educed. This is caused by he ac ha he suppo o he A-pilla should
be ex ended o he C-pilla a ea, unlike wha was done in he p edecesso ehicle se ies, cu en SEAT
Leon, whe e he uppe A-pilla doesn' connec wi h he C-pilla . By leng hening he A-pilla , and no
ha ing an in e media e suppo in he B-pilla a ea, he bending on he zone is e y high, inc easing he
isk o collapse du ing a side impac , and signi ican ly inc easing he in usions in he uppe zone o ha
pilla .
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Figu e 1: Comple e shaped ing, consis ing o pilla A (highligh ed in yellow, he aim o his
p ojec ), pilla B and pilla C
In iew o he esul s in physical es s, i was decided o ini ia e ac i i ies ha enable o ensu e a be e
side c ash pe o mance o he uppe A-pilla in u u e p ojec s.
Resea ch ca ied ou o sol e his p oblem e lec ed ha in case o ha ing an uppe A-pilla made o ho
s amp s eel, ype USIBOR 1500, a much mo e app op ia e beha io is ob ained, o inc ease he ma gins
o sa e y in he e en o side impac .
The s udy also conside ed al e na i es, such as addi ional pieces wi hin he A-pilla , which appea ed
much less e icien , bo h in cos and weigh , han he solu ion based on he use o high s eng h s eels.
Figu e 2: Compa ison o plas ic de o ma ions in he uppe A-pilla du ing Side C ash in he new
Sea Ibiza. Compa a i e de ail o plas ic de o ma ions in he uppe A-pilla in side c ash o he
new SEAT Ibiza
In o de o ca y ou he easibili y s udy o high s eng h s eel o ming p ocess, he CTS Bodywo k
Depa men was eques ed o p opose an uppe A-pilla geome y, and subsequen ly, his geome y was
in oduced in a ini e elemen model o cu en SEAT León o pe o m he necessa y simula ions.
Pilla A
Pilla C
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Figu e 3 shows he s uc u e o he uppe A-pilla ing o cu en SEAT Leon, and he s uc u e de eloped
o his s udy, consis ing o he ein o cemen o he uppe A-pilla , in ed colo , plus he pa ex ended o
each he C-pilla .
Figu e 3: Compa ison o he pa s used in p e ious models oge he wi h he pa s de eloped o
his p ojec
Change o s uc u e in he concep ual simula ion on cu en SEAT Leon (subs i u ion o pa s o se ial
model 100% by pa shaped uppe A-pilla + elimina ion o he oo ‘s cen al beam.
4.2. Requi emen s eques ed o he pa o build
This sec ion desc ibes he equi emen s bo h he new pa de eloped and he manu ac u ing p ocess o
ob ain i mus comply wi h.
The A-pilla is a s uc u al componen o he ehicle ha has o comply wi h he equi emen s de ailed
below:
- S i ness. As a piece o he bodywo k's s uc u e, i mus b ing he necessa y igidi y as an
indi idual pa , as well as in he whole body s uc u e.
- C ash. I mus mee he equi emen s o gua an ee he in eg i y o he compa men in case o
acciden .
- Cos . Like any o he ehicle pa , i is subjec ed o some a ge cos o ul ill.
- Package. Compa men Package is he space a ailable o he occupan s inside he ehicle. Due
o he size o he space a ailable o p o ide, logical es ic ions o he shape o he pa ake
place, since he s ay o he occupan s wi hin i should be as com o able as possible.
- Weigh . As well as cos , weigh is a e y impo an pa ame e , cons an ly con olled and
moni o ed du ing he de elopmen o a ehicle. As s a ed abo e, a dec ease o weigh
au oma ically implies a dec ease in pollu an emissions.
- Vision. Gi en he posi ion o he A-pilla , loca ed in he d i e 's ield o ision, his pa in e e es in
his/he side ision, especially in s ee cu es and u ns. The smalle he sec ion o i , he wide
he ield o ision o e ed and he e o e, g ea e sa e y migh be expec ed.
- Design/Aes he ics. As a pa isible in g ea ex en , whose geome y a ec s and in luences he
colo p opo ions o he body seen, i s size and o ien a ion is an impo an dimension o he
designe .
- Pedes ian p o ec ion. The A-pilla is a pa which a pedes ian could collide wi h, in case o being
knocked down. Tha is why i is essen ial o a oid e y jagged a eas ha can p oduce se ious
inju ies in he e en o an acciden .
Cen al Roo beam elimina ed
(100% se ial pa in cu en
Leon)
Binding pa added o C-pilla by
elimina ion o cen al beam.
ein o cemen o he
uppe A-pilla
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Conce ning he manu ac u ing p ocess, cu en ly he piece is manu ac u ed h ough a cold- o med mic o-
alloyed s eels p ocess o ela i ely low ca bon con en ha o e elas ic limi s in he en i onmen o 220 o
340 MPa in ecei ing s a e (la e on, p o iling inc eases hese p ope ies). This gi es ise o p oduc ion o
he componen h ough he union o up o i e pa s, which in o al weigh 12.2 kg/ca . An al e na i e
solu ion, o which SEAT has al eady some expe ience in he new Ibiza, would be making his pa using
ho s amping and he p ocess is educed o only h ee pa s ha weigh 8.4 kg/ca .
An e en mo e demanding op ion aised in his p ojec , since i is es ima ed ha i could be achie ed wi h
he blow- o ming echnology: o design he en i e pa as a single componen , educing i s inal weigh o
only 7.9 kg/ca .
4.3. Ho s amping p ocess
The ho s amping p ocess is a p ocess pa en ed by he company Linde-Wieman, who pa icipa es as
ou sou ced company in he p ojec . The p ocess consis s o he s eps desc ibed below. Fi s , a p e- o m
o he pa is ob ained h ough adi ional cold o ming/shaping. Subsequen ly, he p o ile is closed, and a
hole and a compa men a e made by welding. Finally, h ough a p ocess o de o ma ion by blow- o ming,
which is he eal no el y o he p ojec , he pa akes on i s de ini i e o m.
The blow- o ming p ocesses all wi hin he ca ego y o luid molding, being he mos cha ac e is ic he
hyd o o ming, mainly applied o cold o ming p ocesses. This ype o p ocesses has he ad an age o
p oducing a uni o m p essu e, on he con a y o classic s amping p ocesses ha can p oduce local
concen a ions o e o s. On he o he hand, since i is possible o con ol a will he p essu e applied o a
empe a u e- ime sequence, i is possible o achie e complex pa s and hicknesses, a he same ime
a iable.
In he case discussed he e, once hea ed he pa , ei he in a con en ional o en o h ough induc ion, i is
inse ed in he o ming ma ix, whe e ai o 300 ba s o p essu e is blown. Once he o m is ob ained, he
pa is cooled in wa e , while i is s ill inside he die, going om 900 o 40 ºC in 10 seconds. Finally, he
ends a e cu o and he holes equi ed a e made by lase o any o he p ocedu e o de ine.
A e he i s mee ings o SEAT and Linde-Wieman, i was clea ha a commi ed solu ion be ween he
cu en geome y o he A-pilla in he new SEAT León and he appa en possibili ies o he blow- o ming
p ocess acco ding o Linde-Wieman's own expe ience had o be sough .
The e o e, he i s s ages o he p ojec ocus on making he needs o SEAT con e ge wi h he
possibili ies o he p ocess. Fo his, CTS p o ides a his s age a new me hodology o inno a ion, which
will allow, a he Concep s age, he c ea ion o a pa ame e ized 3D ma hema ical geome y model. Wi h
he ma hema ical model, de eloped om an ini ial ex e nal su ace co esponding o an ea ly s age in he
de elopmen o he design, a alid esul is ob ained o be able o ini ia e, he simula ions, among o he
ac i i ies. A e successi e i e a ions be ween CTS and Linde-Wieman, and ag eemen was eached on
he inal geome y o manu ac u e and he ma e ial o use. Rega ding he ma e ial, i is clea ha o his
ype o echnology a s eel o easy empe abili y has o be chosen. Howe e , his e ec is no desi able i
he e a e in e media e welding ope a ions. Likewise, he ha denabili y is adi ionally achie ed alloying,
which is usually de imen al o he ma e ial's e y duc ili y in cold. Conce ning his, he e is a endency o
use mic oalloyed s eels wi h bo on, which seems o be a solu ion ha can be combined in his p ocess.
The second s age o he p ocess, welding, equi es a s eel o easy weldabili y. This equi emen goes
agains he equi emen o high ha denabili y, necessa y in he inal s age, and he e o e i is necessa y o
ind a comp omise solu ion. As a esul o he cha ac e is ics o he ma e ials, pa o de elop and p ocess
o be used, wo s eels mic oalloyed wi h bo on a e ini ially chosen o he p ojec : 22MnB5 and 27MnB5.
In bo h cases, i was decided o es wi h and wi hou he coa ing supplied by he manu ac u e . Due o
he ac ha s eel p esen s ha denabili y, i is necessa y o choose a welding p ocess ha , in addi ion o
being as enough o no a ec p oduc i i y, does no p omp s eel c acking. Howe e , i should be
men ioned ha al hough ma ensi ic s uc u es p oduce in welding, since he pa is hea ed la e o he
inal blow-molding, he mic os uc u e disappea s. Thus, he me e appea ance o ma ensi e should no
be conside ed a p oblem, bu he weakening o he ma e ial should, so ha i can c ack while cooling i o
in subsequen manipula ions, be o e he blow- o ming.
The inal mic os uc u e, and he e o e he mechanical p ope ies a e going o depend almos exclusi ely
on he empe ing a e he blow- o ming p ocess. The empe ing, once s eel is ixed, will depend on he
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speed o cooling. In p inciple, a s eel as he USIBOR1500 equi es empe ing speeds o nea ly 70-80
ºK/s, wha heo e ically he blow- o ming p ocess can seemingly accomplish, al hough his also depends
on he hickness o he s eel. In he case o pieces wi h cu a u es and sligh sec ion a ia ions, i is
possible ha no all he piece's pa s cool equally, and he e o e hey ha e di e en mechanical
p ope ies. Hence, how homogeneous is he mic os uc u e and he e y mechanical p ope ies mus be
assessed, and ac acco dingly.
Once he pa is buil , he nex s ep is o de e mine i all he equi emen s eques ed o he A-pilla lis ed
abo e ha e been me . Pa icula ly impo an a e he equi emen s o impac . He e i is wo h men ioning
ha e en hough he pa migh no ha e a comple e mic o-s uc u al homogenei y, i doesn' mean i has
o be uled ou , as long as i mee s he mechanical equi emen s. Fu he mo e, i i has ce ain mic o-
s uc u al he e ogenei ies, hese can be included in he simula ion s age and edesign acco ding o hem.
4.4. In oduced inno a ion and applied echnologies
Technological inno a ion o he p ojec lies mainly in:
- Applied echnology. The echnology is used o shaping wi h ha dening by blow- o ming, o p oduce an A-
pilla .
- De elopmen o a new s uc u al elemen . An A-pìlla which allows subsequen in eg a ion in o he
ehicle's s uc u e is de eloped, in esponse o he inhe en limi a ions o he echnology used and o e ing
iden ical o be e pe o mances compa ed o he exis ing ones, so ha he sa e y o he ehicle is no
al e ed.
- The iabili y o i s indus ializa ion. The de elopmen o he A-pilla h ough he use o shaping echnology
wi h ha dening by blow- o ming mus ace he challenges o he indus ializa ion o his echnology in a
way ha he p o o ypes o de elop may be iable in he u u e, in he con ex o i s indus ializa ion.
- The applica ion o new so wa e ools o he design s age and calcula ion: he i ual echnical model.
Following, he de ailed desc ip ion o he inno a ions he p ojec p o ides.
4.4.1. Shaping Technology wi h ha dening by blow- o ming
The shaping echnology wi h ha dening by blow- o ming is cha ac e ized by exploi ing o he maximum
he ad an ages o each o he p ocesses ela ed:
1. F om shaping. The ad an ages o his p ocess a e:
- Use o closed sec ions.
- T ans o ming ope a ions in eg a ed in o he same shaping p ocess (p e-s amping and pos -
s amping).
- Va iable design o he pa s (e.g. he leng h o he p o ile can be a ied depending on he
equi emen s wi hou he need o new ooling).
- Con olled cos o ooling e sus equi alen cos in s amping p ocess.
- Minimal was e o ma e ial.
2. F om ha dening by blow- o ming. I s ad an ages a e:
- Op imized design o he p ocess: In eg a ion o all ope a ions on he blow- o ming shaping line.
- Sec ion adap able o he con ou : Possibili y o a y he sec ion on an ongoing basis along he
pa .
- Ma e ial ha dened abo e he 1400 MPa based on ma e ial om 500 MPa.
- Excellen ene gy abso p ion o ace impac s.
The echnology is al eady pa en ed by Linde-Wiemann, and i is pa o he a ious p ocesses a ailable o
he company o he ha dening o p o iled pa s. Howe e , despi e he ac ha his echnology is cu en ly
being applied in he au omo i e indus y in o he pa s, such as bumpe s, i is s ill pending o assess hei
easibili y in he de elopmen o o he componen s o he au omo i e sec o , as he A-pilla , mainly due o
he di e en geome ies be ween some componen s and o he and ha hey he e o e equi e o i s on
esea ch, in o de o de e mine whe he he echnology can be adop ed o his ype o pa s.
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Figu e 4 shows he compa ison o sec ions p oposed by Linde Wiemann e sus he o iginal concep o
SEAT Technical Cen e .
Figu e 4: Sec ions used in he analysis o A-pilla
In oducing he longi udinal g oo es in he p o ile ein o cemen by Linde Wiemann, is due o limi a ions in
he p oduc i e p ocess o he pa , which only admi s a maximum o 30% leng hening in he ma e ial
du ing he manu ac u ing p ocess. Since he e a e sec ions adically di e en in he on and back
sec ions o he o med pilla , i is necessa y o in oduce hese longi udinal olds in o de o ensu e he
indus ial easibili y o he pa .
Howe e , he sec ions esul ing om he indus ially iable p oposal in ol e an unlikely unc ional
geome y in he on pa o he uppe A-pilla , especially by equi emen s o he O se shock. This aises
he need o build a ini e elemen model o e lec he design o he new SEAT Leon, because he
geome y o his ein o cemen , he A-pilla , is g ea ly condi ioned by he design o he ehicle i sel .
L&W/Acc a ini ial p oposal, S a us SEAT Leon se ies.
Figu e 5: Compa ison o wo al e na i es o he C-C sec ion
To mee his need o calcula ion, i was sugges ed o build a new wo king ool: The Vi ual Technical
Model.
4.4.2. Vi ual Technical Model
As a new me hodology o inno a ion, in he de elopmen o he new Leon, CTS has de eloped a ool
ha allows he c ea ion o a pa ame e ized 3D ma hema ical geome y model in he Concep s age,
whe e om a ini ial ex e nal su ace (skin), co esponding o an ea ly s age o he de elopmen o he
design, a alid esul is ob ained, o be able o ini ia e he simula ion, among o he ac i i ies.
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Fo i , ini ial epo s ha accompany he men ioned Design a e aken om:
- Package and E gonomics. These gua an ee he desi ed a chi ec u e, he dimensions which
secu e he com o and d i ing space.
- Technical and echnological concep s. These gua an ee he easibili y o implemen a ion o he
p e ious pa ag aph, Package, using he so-called " ypical sec ions" o i .
- Feasibili y S udies. This ac i i y is he main sou ce o in o ma ion o he de elopmen o he
echnical model, since i guides du ing i s cons uc ion and joins he p e ious sou ces.
The p ocess is he ollowing:
1. I s a s om a ' a o i e' design model (in hese phases he e a e o en ou o mo e design
al e na i es).
2. The in o ma ion o his model is minimally adap ed/ ans o med h ough he applica ion o basic
echnical concep s.
3. F om his momen on he gene a ion o he geome y o he echnical model eally s a s,
de eloping he di e en pa s o i sepa a ely (see Figu e 6).
Figu e 6: Technical Model c ea ion p ocess
A b ie desc ip ion o he p ocess is p o ided below:
- I s a s wi h a pa ame e iza ion o common a eas, ge ing a gene al basic su ace. This su ace is
di ided in o segmen s in esponse o pa ame e s o manu ac u abili y, assembly, and concep s o
unions, among o he s.
- Basic su aces a e used o p oduce he i s simula ions o he di e en s a es and load es s.
- Simula ion eedback also eed he Technical Model geome y, as he design con inues.
New in o ma ion on he design (su aces) appea s, so also he echnical model mus be upda ed. Thanks
o his, he cons uc ion o he geome ies is associa ed wi h he design, upda es o he model a e
ela i ely quick o make, enabling us o p o ide a e y sa is ac o y esponse ega ding he ime o
de elopmen (see Figu e 7).
Fa o i e design
Technical
Model
Su aces
Package
Typical
sec ions.
Technical model o he
s uc u e
Technical Model o
S uc u e Cu Pa s
Calcula ion
Calcula ion
Geome y au oma ion in
pa s common o all
a ian s o he same
amily ( he es o he
geome y is buil
manually).
The cons uc ion o
he i s FEM model
( he cu pa s and
he welding a e
made in he model,
wi h he p e ious
ag eemen o he
pa ies in ol ed).
Geome y au oma ion in
pa s common o all
a ian s o he same
amily ( he es o he
geome y is buil
manually).
FEM model
upda e, whe e
app op ia e.
The geome y
wi h cu pa s
and he FEM
model should
coincide.
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