scieee Science in your language
[en] (orig)

Optimization of dosing tank emptying using spiral vibration

Abstract

This article addresses the optimization of a dosing tank using a spiral harmonic motion. The dosing tank is used for ashort-term storage of cohesive sand, which is then released into a tubular mold. Originally, a solution based on the principle of wiping the material using rotary blades and brushes was used to fill the molds. However. this method was not effective enough. This solution suffered from uneven dosing as well as a loss of material. The mold filling time ranged around 20 seconds. During the course of optimization of the dosing tank, a new design of the tank was created and external energy in aform of harmonic spiral vibrations was introduced into the system. The chosen shape of the harmonic spiral motion proved to be the most suitable for continuous emptying of the cohesive sand from the dosing tank into the tubular mold in a very short time. There was also a significant elimination of material losses. It was determined that the frequency of harmonic motion affects uniform dispensing of material fromtanks.

Read accessible full text

Optimization of dosing tank emptying using spiral vibration

Author: Žurovec, David
Publisher: Lublin University of Technology
Year: 2018
DOI: 10.12913/22998624/94962
Source: https://dspace.vsb.cz/bitstreams/633d0c5b-99a9-4602-ab7e-fdb0d5fa4e8e/download
Ad ances in Science and Technology
Resea ch Jou nal
Volume 12, No. 3, Sep embe 2018, pages 143–149
DOI: 10.12913/22998624/94962 Resea ch A icle
OPTIMIZATION OF DOSING TANK EMPTYING USING SPIRAL VIBRATION
Da id Zu o ec1, Jan Necas1, Jan Di is1, Jakub Hlos a1, Ji i Zegzulka1, Ka e ina U bano a2
1 VSB-Technical Uni e si y o Os a a, ENET Cen e, 17. lis opadu 15/2172, 708 33 Os a a-Po uba, Czech
Republic, e-mail: da id.zu o ec@ sb.cz
2 DSD-Dos al, a.s., Bys icka 38, 751 14 D e ohos ice, Czech Republic
ABSTRACT
This a icle add esses he op imiza ion o a dosing ank using a spi al ha monic mo-
ion. The dosing ank is used o asho - e m s o age o cohesi e sand, which is hen
eleased in o a ubula mold. O iginally, a solu ion based on he p inciple o wiping
he ma e ial using o a y blades and b ushes was used o ill he molds. Howe e , his
me hod was no e ec i e enough. This solu ion su e ed om une en dosing as well
as a loss o ma e ial. The mold illing ime anged a ound 20 seconds. Du ing he
cou se o op imiza ion o he dosing ank, a new design o he ank was c ea ed and
ex e nal ene gy in a o m o ha monic spi al ib a ions was in oduced in o he sys-
em. The chosen shape o he ha monic spi al mo ion p o ed o be he mos sui able
o con inuous emp ying o he cohesi e sand om he dosing ank in o he ubula
mold in a e y sho ime. The e was also a signi ican elimina ion o ma e ial losses.
I was de e mined ha he equency o ha monic mo ion a ec s uni o m dispensing
o ma e ial om anks.
Keywo ds: spi al ib a ion, dosing ank, cohesi e sand.
INTRODUCTION
Indus ial en e p ises a e o ced o in es in
he de elopmen o echnology due o echno-
logical ad ances in all disciplines o mechani-
cal enginee ing and e e -inc easing demands o
speedy manu ac u ing p ocesses.When designing
anspo and s o age acili ies, i is app op ia e
o use s udies and knowledge om a ious a eas
o anspo and handling equipmen designed
no only o bulk ma e ials [1, 2, 3]. The p esen
s udy add esses he op imiza ion o emp ying a
dosing de ice designed o he sho - e m s o age
o an exac amoun o cohesi e sand. In gene al,
s o age acili ies such as anks o silos a e used
o hold loose ma e ial in a closed space o he
necessa y amoun o ime. The cons uc ion o he
s o age acili ies is dimensioned acco ding o he
equi ed s o age ime as well as he mechanical
and physical p ope ies o he s o ed bulk ma e-
ials. Mechanical and physical p ope ies signi i-
can ly in luence he beha io o bulk ma e ials
in s o age p ocesses [4, 5, 6]. In ac , nega i e
beha iou such as aul ing a e no uncommon
du ing emp ying anks. The op imal emp ying o
anks equi es knowledge o he ope a ing con-
di ions and de ailed in o ma ion abou he s o ed
ma e ial. This abo e all includes he a o emen-
ioned mechanical and physical p ope ies o he
s o ed ma e ial, he shape and size o he ank, he
hoppe and he discha ge opening. In e ms o he
na u e o he ank emp ying, we dis inguish wo
ways o ma e ial low: mass and co e low. Mass
low is mani es ed by he g adual d aining o ma-
e ial om he ank in o de , in which i was in o-
duced o he ank. To achie e his, an op imal con-
s uc ion design o he s o age de ice is equi ed
depending on he p ope ies o he s o ed ma e ial
[7]. Howe e , in eali y his is o en no achie ed,
and i equi es he use o ex e nal sou ces o en-
Recei ed: 2018.06.29
Accep ed: 2018.08.01
Published: 2018.09.01
Ad ances in Science and Technology Resea ch Jou nal Vol. 12 (3), 2018
144
e gy, such as ib a ions, acous ic wa es o ai
[8, 9, 10]. The co e low is cha ac e ized by he
p inciple ha he ma e ial loaded in he ank i s ,
discha ges las . He e, he ma e ial abo e he dis-
cha ge opening is discha ged i s and he ma e ial
adjacen o he walls o he ank emains s ill, c e-
a ing so-called “dead zones”. The ma e ial loca -
ed in such “dead zones” o en adhe es o he walls
o he ank due o longe s a ic pe sis ence, which
is pe cei ed as a ailu e s a e [11, 12]. O he ail-
u e s a es including s a ic aul s, ca i ies o un-
nels may also occu in s o age de ices, which all
nega i ely a ec con inuous emp ying. Howe e ,
he ad ancemen o echnology p o ides me hods
such as he Disc e e Elemen Me hod (DEM),
o de ec and moni o ailu e s a es in anspo
and s o age acili ies. The ad an age o using he
DEM simula ion me hod lies in so wa e e i i-
ca ion o planned changes in design o a de ice
being de eloped o op imized [13, 14].
DESCRIPTION OF THE CURRENT
TECHNOLOGICAL PROCESS
Du ing he cou se o his esea ch, an analysis
o he cu en echnology o sand dosing in o u-
bula molds was pe o med. The echnology was
de eloped many yea s ago and i no longe mee s
oday’s equi emen s. The exis ing echnology is
based on he p inciple o wiping sand wi h a o al
dose weigh o 4 kg in o a ubula mold using o-
a y blades and b ushes loca ed in a cubical dosing
ank. Fig. 1 summa izes he dosing me hod in o
h ee s eps: I, II, III. In he i s s ep (I), he dos-
ing ank a i es abo e he pai o openings o he
ubula mold and he discha ge ou le is opened. In
he second s ep (II), he p ocess o ma e ial wip-
ing using a sys em o o a y blades and b ushes is
ini ialized. This p ocess akes place o almos 15
seconds. In he hi d s ep (III), he dosing ank e-
u ns o he illing a ea o s a a new illing cycle.
Du ing he illing o he dosing ank, he ubula
mold is p epa ed o he nex illing cycle.
Howe e , his me hod was no e ec i e
enough as i o en esul ed in une en dosing and
ma e ial loss, as shown in Fig. 1 in s eps (I) and
(III). Fu he mo e, he mold illing ime was no
longe su icien o mee cu en equi emen s
and i was necessa y o p oceed o a comp ehen-
si e op imiza ion o he p ocess. The aim o he
op imiza ion was o ensu e a uni o m illing o
he ubula mold o elimina e ma e ial losses as
well as dec ease he illing ime by wo- hi ds.
In he i s s ep o he op imiza ion, he cu en
s a e was e alua ed while he mechanical and
physical cha ac e is ics o he sand we e mea-
su ed. Based on he da a collec ed abou he p o-
cess and he bulk ma e ial used, he op imiza ion
di ec ion was de e mined. Du ing he cou se o
op imiza ion o he dosing ank, a new design
o he ank was c ea ed and ex e nal ene gy in
a o m o ha monic spi al ib a ions was in o-
duced in o he sys em.
Fig. 1. The p inciple o dosing cohesi e sand in o ubula molds [15]
Fig. 2. A sample o sand used du ing he expe imen
145
Ad ances in Science and Technology Resea ch Jou nal Vol. 12 (3), 2018
MECHANICAL AND PHYSICAL
PROPERTIES OF SAND
In o de o op imize he p ocess o emp ying
he dosing de ice, a sample o he bulk ma e ial
was analyzed. The bulk ma e ial used he e was he
sand used o he p oduc ion o i ings in he
ound y indus y, which is shown in Fig. 2.
Angle o in e nal ic ion φe
The angle o in e nal ic ion φe cha ac e izes
low p ope ies o bulk ma e ials. This includes
mo emen s, esis ances and bonds be ween indi-
idual pa icles. The angle o in e nal ic ion de-
e mines he shea p ope ies o he mass, which
de ine he lowabili y o he sample being exam-
ined. The angle o in e nal ic ion was measu ed
using a ing shea es e Schulze RST-01. Fig. 3
shows he esul s o measu ing he angle o in e -
nal ic ion o he sand (φe = 43°). The dependence
o no mal s ess σ on shea s ess τ is shown as
well. Based on he measu ed alues o he angle
o in e nal ic ion o he sand, i was necessa y o
p o ide mo e ene gy o o e come he in e -pa i-
cle bonds and esis ances.
Wall ic ion angle ϕw
The measu emen o he wall ic ion angle
was pe o med on he Jenike di ec shea es e .
The measu emen p inciple consis s o measu ing
he ime dependence o he shea s ess τ, which
is equi ed o shi bulk ma e ial o e he con ac
ma e ial, while g adually inc easing no mal s ess
σ. The ollowing con ac ma e ials we e used: A)
s ainless s eel shee ; B) Mu eld s anda d “S”
plas ic; C) polyu e hane. The esul s o measu ed
alues o wall ic ion angle ϕw and he wall ic-
ion coe icien μw a e summa ized in a single
g aph, which is shown in Fig. 4. F om a compa i-
son o he esul s o ex e nal ic ion measu ed
on indi idual con ac ma e ials, i is seen ha he
s ainless-s eel shee exhibi ed he lowes esis-
ance o mo emen .
Angle o epose Ψs
The angle o epose was measu ed using a
measu ing s and consis ing o a s eel bowl on
which he ma e ial was g adually ed h ough a
ib a o y eede . The bowl was placed on a o a y
s and ha allowed he pile o be moni o ed om
0° o 360°. The nume ical angle o epose alues
a e shown in Table 1, while Fig. 5 shows g aphi-
cal esul s o he angle o epose measu emen s.
The a e age angle o epose was Ψs = 52.1°. This
implies ha sand is e y cohesi e when illed and
emp ied du ing s o age p ocesses.
Pa icle size dis ibu ion
A CILAS 1190 lase pa icle size analyz-
e was used o g anulome ic analysis o he
Fig. 3. Resul s o in e nal ic ion and lowabili y
measu emen using he RST-01 es e
Fig. 4. Resul s o wall ic ion angle measu emen s
Table 1. The nume ical angle o epose alues
Posi ion
1 2 3 4 5 6 7 8
Angle o epose 52.6 53.4 52.4 52.09 52.3 50.2 51.1 51.8
Angle o epose-A g. 52.1
Ad ances in Science and Technology Resea ch Jou nal Vol. 12 (3), 2018
146
sample. Cohe en ligh om low-powe lase
diodes, emi ed a 830 nm wa eleng h, passes
h ough a cu e e con aining a sample o he
analyzed ma e ial dispe sed in he co espond-
ing liquid and he ligh beam issca e ed. The
pa icle size dis ibu ion o sand anges om
1μm o 600 μm, see Figu e 6. Mos pa icles in
he sample anged om 100 μm o 400 μm.
OPTIMIZATION OF DOSING TANK
Based on he measu ed mechanical and
physical p ope ies, sand was added in o a g oup
o cohesi e ma e ials and an ex e nal powe
sou ce was equi ed o uni o m emp ying o
he dosing de ice. Mic o- ib a ions wi h spi-
al pa h oscilla ion we e selec ed as an ex e nal
powe sou ce. The shape o he spi al ib a ion
was achie ed by using a pai o NO12 ib a ion
Fig. 5. Resul s o angle o epose measu emen s
Fig. 6. Resul s o pa icle size dis ibu ion measu emen s
Fig. 7. a) new design o he dosing de ice, b) expe i-
men al s and
a)
b)
147
Ad ances in Science and Technology Resea ch Jou nal Vol. 12 (3), 2018
mo o s ins alled on he ib a ing pa and o-
a ed by 90° wi h espec o each o he , see Fig.
7b). Vib a ion mo o s posi ioned his way p o-
ide a combina ion o wo ha monic mo ions:
pa ial o a ion a ound he “Z” axis and pa ial
eed in he “Z” axis. The combina ion o hese
wo mo ions c ea es spi al mic o-oscilla ion.
In his way, he s abili y and symme y o he
o e all assembly du ing g a i a ional emp y-
ing o he dosing ank a e ensu ed. F om he
measu emen o he ex e nal ic ion angle, a
s ainless-s eel shee was chosen o he p oduc-
ion o he dosing ank. Based on a comp ehen-
si e assessmen o he measu ed mechanical
and physical p ope ies o he used sand, a new
shape and size o he ank was designed, and
he minimum dimensions o he discha ge ou -
le we e de e mined, depending on he pa icle
size dis ibu ion o he sand. Figu e 7 shows: a)
new design o a dosing de ice, b) expe imen-
al measu ing s and. The expe imen al measu -
ing s and consis s o he ollowing basic pa s:
1-Fixed ame; 2-Flexible Elemen s 4x; 3-Vi-
b a ing pa including he dosing ank; 4-Vib a-
o mo o s NO12.
EXPERIMENT AND RESULTS
In o de o expe imen ally e i y he unc-
ionali y o he op imized dosing ank, a measu -
ing appa a us was assembled consis ing o he
ollowing: a PC, expe imen al s and, ensome ic
scale and equency con e e . The assembly o
he measu ing appa a us is shown in Figu e 8.
Du ing he expe imen al measu emen s, he e -
ec o ib a ions on he e iciency o emp ying
he dosing ank was assessed. Table 2 shows se -
ings o he d i ing o ce FB depending on he os-
cilla ion equency p oduced by pai o he N012
0.15kW ib a ion mo o s. The o al s i ness em-
ana ing om he ou elas ic elemen s was kp =
123N.mm-1. A 4 kg sand sample was loaded in o
he dosing ank.
Figu e 9 shows he emp ying p ocess o he
dosing ank in a ious ope a ing modes. In he
i s expe imen , he sand beha io una ec ed
by ib a ions was moni o ed. I u ned ou ha
he ma e ial is so cohesi e ha he ank could
no be emp ied by employing only a g a i a-
ional me hod. In he second expe imen , i-
b a ions o 15Hz equency co esponding o
a d i ing o ce o 325N we e used. E en in
his case, he sand could no be emp ied om
he ank and he en i e olume emained in he
ank. A e inc easing he equency o 20Hz,
he sand s a ed o eely low immedia ely
a e opening he discha ge ou le . The emp-
ying p ocess was smoo h wi h only sligh de-
ia ions. Subsequen ly, he ib a ion equency
was se o 25Hz, which co esponds o he d i -
ing o ce o 904N. In his case, he emp ying
was e y smoo h and s able wi hou signs o
impac e ec s. A 30Hz, he e we e signs o
g ea e dynamic e ec s du ing he emp ying
p ocess, which a e undesi able o he ollow-
ing p ocesses. The emp ying ime o he es ed
equencies was a ound 2.5s.
Based on he esul s om he expe imen-
al es s, he inal design o he dosing ank was
c ea ed, and sui able pneuma ic ib a ion d i es
we e selec ed which we e posi ioned 90° ela i e
o each o he . The d i ing o ce o a pai o pneu-
ma ic ib a ion d i es was se o allow he op i-
mal emp ying o he dosing ank. Fig. 10 shows
he inal e sion o he dosing ank design used in
eal ope a ion.
Fig. 8. Assembly o he measu ing appa a us
Table 2. Se ings o he d i ing o ce FB depending
on he oscilla ion equency p oduced by pai o he
N012 0.15kW ib a ion mo o s
F equency
[Hz]
15 20 25 30
Speed
n [ pm]
852 1136 1420 1704
D i ing o ce
FB [N]
325 579 904 1302

Ad ances in Science and Technology Resea ch Jou nal Vol. 12 (3), 2018
148
CONCLUSIONS
The aim o his esea ch was o op imize
he me hod o emp ying a dosing de ice de-
signed o weighing and sho - e m s o age o
sand. Fi s ly, an analysis o he cu en p o-
cess echnology was pe o med. In he ollow-
ing s ep, he mechanical and physical p ope -
ies o he used sand we e measu ed, namely:
angle o ic ion, wall ic ion, angle o e-
pose and pa icle size dis ibu ion. Based on
he measu ed alues, he sand was assessed
as e y cohesi e wi h a pa icle size anging
om 1μm o 600μm. I was ound, ha he
mos sui able con ac ma e ial o he p o-
duc ion o he inne space o he dosing ank
was s ainless s eel, which showed he lowes
esis ance o sand mo emen . On he basis o
he collec ed da a, a new shape and size o he
dosing ank was designed, and he minimum
size o he ou le was de e mined, depending
on he pa icle size dis ibu ion o he sand.
Due o he high cohesion o he sand, i was
necessa y o in oduce ex e nal ene gy o he
sys em. The mos sui able ib a ions o he
p ocess we e selec ed. The shape o he ib a-
ion, in he o m o ha monic spi al mo ion,
p o ed o be he mos sui able o he uni o m
and symme ical discha ge o sand om he
ank. The expe imen al es s showed ha he
op imal d i ing o ce o a pai o ib a ion
d i es was 900N, depending on he weigh
o he ib a ing pa s and he s i ness o he
lexible elemen s. The emp ying ime o he
equi ed olume o sand anged a ound 2.5
seconds. Op imiza ion o he emp ying me h-
od me all equi emen s and was applied o
eal-li e ope a ion.
Acknowledgemen s
This pape was conduc ed wi hin he ame-
wo k o he p ojec LO1404: Sus ainable de-
elopmen o ENET Cen e,p ojec SP2018/47:
Calib a ion and expe imen al de ices o he
esea ch and alida ion o simula ion models
AND p ojec SP2018/132: Resea ch and de el-
opmen o inno a i e anspo equipmen o
e i ica ion DEM me hod in p ocess o bulk
solid anspo a ion.
Fig. 10. Dosing ank design
Fig. 9. The cou se o dosing ank emp ying p ocess
149
Ad ances in Science and Technology Resea ch Jou nal Vol. 12 (3), 2018
REFERENCES
1. Klepka T., Debski H., Ryda owski H. Cha ac e is-
ics o high-densi y polye hylene and i s p ope ies
simula ion wi h use o ini e elemen me hod, Po-
lime y, 54(9), 2009, 668-672.
2. Fedo ko G, Molna V., Do ica M., e al The use o
indus ial me o omog aphy in he ield o main-
enance and eliabili y o ubbe - ex ile con eyo
bel s in closed con inuous anspo sys emsm,
Eksploa acja i niezawodnosc-main enance and e-
liabili y, 18(4), 2016, 539-543.
3. Jachowicz T., Siko a R.Me hods o o ecas ing o
he changes o polyme ic p oduc s p ope ies, Po-
lime y, 51(3), 2006, 177-185.
4. McGlinchey D. Bulk Solids Handling: Equipmen
Selec ion and Ope a ion. Book: Blackwell Pub-
lishing L d., 2008, pp: 304.
5. Schulze D. Powde s and bulk solids: beha io ,
cha ac e iza ion, s o age and low. Book: New
Yo k: Sp inge , 2008, pp: 511.
6. Ekmann J. M. and Le P. H. Coal S o age and T ans-
po a ion. Re e ence Module in Ea h Sys ems and
En i onmen al Sciences, om Encyclopedia o
Ene gy, 2004, 551-58.
7. Schulze D. Flow P ope ies o Powde s and Bulk
Solids [online]. [ci . 2014-04-10]. Accessible om:
h p://www.die ma -schulze.de/g dle1.pd .
8. Zhang Ch., Qiu C., Pu Ch., Fan X. and Cao P. The
mechanism o ib a ions-aided g a i a ional low
wi h e e hanging s yle in hoppe , Powde Technol-
ogy, 327, 2018, 291-302.
9. Nedde man R.M., Tūzūn U. and Tho pe R.B. The
e ec o in e s i ial ai p essu e g adien s on he
discha ge om bins, Powde Technology, 35(1),
1983, 69-81.
10. Fe a i G. and Bell T.A. E ec o ae a ion on he
discha ge beha iou o powde s, Powde Handing
P ocess, 10(3), 1998, 269-274.
11. Be uola D., Volpa o S., Canu P., San omaso A.
C. P edic ion o Seg ega ion in Funnel and
Mass Flow Discha ge, Chemical Enginee ing Sci-
ence, 150, 2016, 16-25.
12. Tian T., Su J., Zhan J., Geng S., Xu G. and Liu X.
Disc e e and con inuum modeling o g anula low
in silo discha ge, Pa icuology, 36, 2018, 127-138.
13. Clea y P.W. La ge scale indus ial DEM mod-
elling. Enginee ing Compu a ions, 21(2/3/4),
2004, 169-204.
14. Höhne D., Wi z S., Sche e V. A s udy on he in-
luence o pa icle shape on he mechanical in e ac-
ions o g anula media in a hoppe using he Dis-
c e e Elemen Me hod, Powde Technology, 278,
2015, 286-305.
15. SEEIF Ce amic, a.s. [online]. SEEIF Ce amic, 2018
[ci . 2018]. Accessible om: h p://ce amic.cz/.